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James4

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  1. James4
    New Year's Eve 2012, was chilly around 2 degrees C. But the skies were improving and Jupiter was shining through the thin cloud cover.
    I had just picked up a 'Celestron Neximage 5' and was hoping it would clear enough to give it a run.
    I set up the CGEM and put the C9.25 on board. Jupiter was in and out the clouds as I hooked up the Neximage.
    Flashback
    About 2 years ago I was imaging with a pocket digital camera (a Pentax Optio E30). I had surprisingly good results from this non astro camera.
    But eventually I seemed to hit a barrier on improvements. The images were noisy and I couldn't get past a certain level.
    I figured when I upgraded my DSLR to one that shoots video, the better chip would be lower noise and higher quality and would take me to the next level.
    Survey says XX.
    It just didn't turn out that way. The images seemed to have almost no colour and were not even quite as good as those from the $150 Pentax.
    The cost of a real planet camera was out of reach, so I fell away from it. Recently observing Jupiter I decided I needed to try imaging again.
    I decided to try a planet camera instead of messing around with not astro cameras. I still can't justify the money for a high end camera, but saw the Celestron Neximage 5 - a 5 MegaPixel Planet Camera. I reasoned if this can improve my imaging over the other cameras, the next step will be a monochrome cooled camera.
    I'm not expecting brilliant results, but do hope to see an improvement over previous efforts.
    Back to New Year's Eve
    I removed the eyepiece and put the Neximage 5 in its place. On the computer I could see Jupiter a s a large cloud, I refocused and it was just a few turns of the stock focuser to bring Jupiter to focus. Jupiter was still facing in and out of the clouds. I hit the record button quick to at least capture a few frames.
    I changed the resolution up to 2592 x 1944 and Jupiter looked huge on screen. Over the next two hours I captured about 20 video clips of Jupiter.
    I twice put the camera away only to be wowed visually and sparked into taking more video. However, later all the videos turned out to be low resolution.
    I had tried many different resolution settings on-screen but they had all come out at low res!
    Meanwhile back at the scope, I decided to bring out the new 10" Lightbridge. I recently sold my 6" Explore Scientific Refractor and picked up a Lightbridge.
    I used a 5mm 2" Ultima LX eyepiece for 255x on the Lightbridge. The view was excellent, Jupiter was crisp and 5 belts were visible. As far as I could tell there was no GRS or other large features on the nearside of Jupiter. I compared the view in the 10" Lightbridge with the 9.25" SCT. The view looked the same to me, I couldn't really see any difference - I was using 184 x (13mm Ultima 2") in the SCT.
    I decided to look for Comet 2012 K5/Linear. I googled the coordinates and punched them into the CGEM Handcontroller. I slewed there and hunted around for a few minutes. Then just below two faint stars there it was - a small but distinct cloud. I observed it for a few minutes before moving back to Jupiter.
    I tried an OIII filter in the Lightbride to look at The Orion Nebula. The Trapezium almost disappeared, but the nebula eppeared larger and more extended.
  2. James4
    I've had the AR152 up for sale since I got the C9.25 reasoning that The C9.25 should be able to do everything the Refractor can do and with more aperture.
    But I never had the chance to put them head to head. The SCT can operate at F/10 with a focal length of 2350 mm - a nice long focal length for planets.
    With the reducer lens it can operate at F/6.3 an effective focal length of 1480 mm - getting down to reasonably low power for wide field cruising.
    I had over spent the scope budget last year and so decided to liquidate the Refractor - despite it not really having a good chance to prove itself.
    Previously the AR152 outgunned my Astro-Tech AT8in - an 8" Imaging Newtonian - on a Jupiter shadow transit.
    Although the Astro-Tech has an oversized secondary mirror I still thought the 8" of aperture would over rule the 6" Achromat.
    But not so, it was a clear shut out for the refractor. Conditions were a little murky and I could not even detect the shadow with the Newt.
    It was clear on the refractor and I switched back and forth twice to make sure conditions hadn't changed.
    So, finally tonight - nice warm and dry conditions on a weekend night - when does that ever happen?
    I started with the SCT on the CGEM mount. I aligned and looked at the Ring Nebula. The Moon was about 3/4 phase so the sky was a murky light grey.
    The Ring didn't look good and I decided not to use it for comparison. I slewed over to M27 and even in the light sky it was easily visible.

    I inserted my new Celestron UHC filter in the 2" diagonal and it did improve the image quite noticeably.
    I soaked in the view with a 22mm Ultima LX eyepiece (67x). Then I set up the AR152 on the Alt Az - T-Mount.
    I eyeballed where the SCT was pointing and just tried to angle the Refractor in the same position. It was mounted very low on the alt az and I had to do some driveway crawling to maneouvre it.
    I looked again at M27 through the SCT and memorised the view. Then to the AR152. I moved the whole Eyepiece/Diagonal/Filter combination over to the refractor. I centred M27 and then changed to the Ultima LX 13 mm e.p. (76x) to better match the magnification.
    I looked - and Wow! - the refractor put up a view every bit as bright and distinct as the SCT. But that just should not be so - the refractor was giving up 3 1/4
    inches of aperture. I looked long and hard and tried to imprint the view.
    I moved back to The SCT - switching the optical train over again and then dropping to the 22 mm again.
    Nope, the view was not quite as good. It was just less distinct - perhaps less contrasty is the best description.
    I took out the UHC filter on The SCT and the view was worse - looking very grey.
    Debra arrived home and I asked her to look through both scopes.
    She immediately voted for the refractor and said it just looked 'crisper' there.

    I started to think of the possible reasons why the SCT was not clouting the Refractor with its greater light grasp and higher resolution.
    I figured while using the F/6.3 Reducer, the SCT was using 2 lenses and 3 mirrors before the eyepiece:
    the corrector
    the primary mirror
    the secondary mirror
    the reducer lens
    the diagonal
    Whereas the refractor was using:
    the objective lens
    the diagonal
    Since each time light is reflected or passes through a lens some if it is lost, it seems likely this must be a big factor?
    But still - there's no way my C9.25 should be beat on deep sky by a 'big daft achro' as I have sometimes referred to it.
    I've cancelled the sale (not kidding) of the achro pending a planetary shoot-out. There's just no way the Achro can win this one.
    The C9.25 is legendary on planets and the Achro is going to have a blizzard of CA pouring out the eyepiece.
    I'm thinking Jupiter here ....
    But I would have dismissed any chance of it winning on deep sky - so who knows?
    I tried the OIII filter but the sky was just too blown out by The Moon do find anything else worth comparing.
    I did pull in Epsilon Lyra - The Double Double, and neither scope could cleanly split them - the stars appeared dazzling and a little spikey.
    A clear tie on this object.
  3. James4
    Just back from The Table Mountain Star Party in Central Washington. It was our first star party proper (overnight) - and our astro pal Neil had persuaded us we were ready for the big one - all night under the stars with some serious astronomers ... He also persuaded us with stories of buying hot dogs at 1.00 am ... There would be caterers and scope gear vendors all there too.
    We couldn't find an RV for rent - they were rented out months in advance so we settled on a mini van. It was a Kia Sedona - big enough to carry all our gear - and civilised enough (compared to a cargo van) for sleeping in. I hate camping - its the sleeping in a tent I really dislike - problem is you hear everyone else snoring - off gassing (trying to be polite here) - playing their ghetto blasters etc into the wee hours ... I figured a sleeping bag and a van will do me!
    First stop the Canada/US Border. I have a UK Passport and a Canadian Citizinship card. But the US Border guards said "what's this? I'm not interested in your citizenship card" and we don't like your UK passport. So into the office for some form filling out and questions. At that point I was thinking we could be heading home. I noticed the guard advising us on form filling had a slight accent. I asked him if he was English? He looked at me and said "Scottish". OK being Scottish myself, that's the first time I have asked a Scotsman if he was English!
    I love it when my Canadian colleagues refer to me as English - I respond with "Scottish actually, but that's O.K. I know you Americans get confused".
    Canada and The US are so Scotland/England - Canadians are staunchly not US and don't get us confused! But the Americans love Canada, they go hunting, fishing and boating up here and enjoy driving on roads with nobody else for miles. So back to the US Border Guard - he then tells me he was in the Highland Fusileres and showed me his Highlander's Crest attached to his Stamp (the one he stamps Accepted/Rejected on your passport with). The other guard came back from searching the van with a shell shocked look on his face. "Are you taking enough for everyone?" he queried. Now we had three guards listening into our conversation about all things Scottish and Astro .... They also told us to watch out for traffic around Seattle because Chelsea were playing The Seattle Sounders that night. Thinking that might not have turned out well for The Sounders! We were charged $6 for the entry application form and told to head on in (to The US).
    It was a nice day for driving south - cloudy with sunny breaks - not too hot. After several stops for lunch, tea, loos, etc, we rolled into Ellensburgh Washington - the nearest town to Table Mountani (about 20 miles from the mountain top) just before 9pm. A little later than I would have liked as I had been told it is a bit tricky finding the mountain access road from town. I stepped out the van and it was 27 C outside - at 9 pm! I gassed up the van - US Gas price was only $3.88 a gallon, not far from half the Canadian price (despite our bigger gallon). I bought a map and we headed for the mountain.
    Even in Ellensburgh I was still unclear where exactly this mountain was. There are several lowish looking mountains somewhat distant from the town and I couldn't decide which one was ours. I learned later, Elinsburgh is already at 1500 plus feet.
    It soon became clear as we headed North of Ellensburgh. A half hour later we were still pulling over to read the map - we kept heading back towards town. Finally we snagged the elusive Reecer Creak Road - the fire road up the mountain.
    The first mile was gentle, the next mile was hair raising with a roller coaster angle of attack and no guardrail on the single track road (it was paved at least). After that it wound with switchbacks up into the forest. The sun was sinking lower in the sky - I guessed about 20 minutes until sunset. Still we climbed - not another vehicle in sight. Can anyone else really be up here? Have we got the right mountain? The tarmac ran out and we bounced for several miles on a dirt road. The sun was almost down as we rounded a corner and looked across an alpine meadow - wowa! - there it was - a city of white gleaming (and giant) RV's Every sized motor home parked in a line across the mountain top - shining in the last rays of sunlight. 700 people on top of a 6,370 ft mountain. It was quite the sight.

    We were ushered to a parking area and found our astro pal Dan already there saving a space for us. We set up camp quickly and I unloaded the scope gear and as much of the other gear as possible - since I was sleeping in the van.
    That night turned out to be clear right through until morning. It had been a long drive but I wasn't taking a night off just in case the weather turned bad. I had my SCT setup on the CGEM by dark. Saturn was lowish in the West but I slewed there and found a nice view at 180x. The Cassini Division was just on the brink of visibility. But I was really just waiting for dark. By 11.30 pm it was 90% dark. I moved the mount to point at Polars (just eyeballed it) and there the mount stayed for the next 4 nights. The Ring Nebula was my first deep sky quarry. A very nice view I thought. My astro pal Dan and I then spent some time trying to decide whether this mountain top sky was indeed any darker or any clearer than our own back yards, and the local Airport (Sechelt). Were we just dark adapted and so it seemed similar? Or was it pretty samey? Dan pointed out that lots of people here live in Seattle or Renton and don't normally see a dark sky - so for them this would be a huge difference, but for us living near a smallish town it was not so drastic a change. Either way, The Milky Way was bright overhead the whole night and it stretched from North of Cygnus right down through Sagittarius to the horizon.

    Later at 1.00am Debra and I decided to walk around to the main scope field. Because we arrived near dusk, we had been ushered to the overspill area - still a very nice spot - but with more relaxed rules about coming and going and lights etc. On the way to the main scope field I encountered a Hot Dog stand! It was actually a full catering setup with tea, coffee, burgers, dogs, etc. We then wandered the main scope field looking for big scopes - I paused and used my red light only to see my hot dog. We soon found Dean setting up his 12 and a half inch Plane Wave SCT. He was aligning and had to brush off a slightly rude visitor who was trying to tell him which NGC Object he wanted to see. He soon left and I asked Dean if it was OK for us to hang around and watch. Of course he said and soon he had The Ring Nebula in the scope. Debra went to the eyepiece first - there was a pause and then 'OMG' - she gasped at the nebua. Next it was my turn - I had seen the ring hundreds of times - what could be so surprising? I looked I thought for a second or two - what is this? Then I too gasped - it was huge and bright! Normally you see the ring either huge or bright - not both! Through the Plane Wave at 280x I could see the smeared top edge of the ring and the star that sits top right. I have looked at the ring through many scopes including a couple of 17 inch Newtonian's but this was in a different league.
    When we returned to our own scopes around 2.30 am I immediately slewed The Niner (C9.25) to The Ring. I looked at 180x. Compared to what I had seen with the Plane Wave, my view was like using a 60 mm toystore scope. It will take a while to erase that Hubble Like view of The Ring. We observed the sky from the region of the big dipper - behind us just above the trees - right overhead through Cygnus and down between Sagittarius and Scorpio. Finally at 3.30 am my early rise and 500km drive had caught up with me. The rear hatch of the van had been opened all night - I hoped the Mozzies had gone to bed by now (their own beds, hopefully) and I got into the van and my brand new sleeping bag. It was the 'mummy' type which looked real cosy on the shelf of Walmart but I soon discovered it was too cozy and very difficult to turn over in - you are forced to either sleep face up or face down, neither of which are very comfortable.
    I woke up at 4.00am and had to head to the porta loos. When I stumbled out of the van still half asleep I was met with the dazzling sight of Jupiter and Venus rising in a dark blue sky in the East. I stopped and just took in the view for a few minutes before continuing on my way.

    Later around 9 am the sun was already starting to cook the van and any tents that did not have shade. It was shorts and sandals throughout the day in around 28 C heat.
    (Yikes seem to have lost a big chunk of my blog here - was updating it from another computer)
    We spent the day drifting through the different scopes, attending presentations by different astronomy related speakers and heading back to our sun tent to rustle up lunch. Also spent a good deal of time at our own scopes with visitors asking us various questions about our scopes and about the sun.
    I looked through a Meade 152 ED Apochromat and through a Meade 8" SCT - both using Baader. Our astro pal Dan had his Lunt 60mm double stacked Ha scope and its views are always a knockout - he had a steady stream of visitors to his scope.
    Just before lunch we noticed a large orange tube SCT - it was a Celestron C14 on a CG-PRO mount. Quite the beast we thought. nearby was a Meade Maksutov 7" - nice I thought. Then I looked at Debra and she was pointing without saying anything ... I turned around to see the fabled Questar. But not a 3.5 inch desktop one, It was the Big Daddy Questar - 7" and mounted on a wedge - its chromed base gleaming in the sun. We knew we had to go drag our astro pal Dan round to see this! The owner informed us these three scopes belonged to Belevue College and he was evaluating them for the astronomy class. Three of the class students were sitting at a table doing their homework and were puzzled what all the fuss was about. They had been viewing through the lengendary Questar each night - unaware of its mythical status and history.

    Late afternoon soon arrived and we had our dinner tickets in our pockets. I expected there would be a dinner tent with benches or something similar, but it was more BYOC - Bring Your Own Chair. The food was excellent and was professionally catered but it was quite awkward trying to balance your paper dinner plate, a plate of desert and a drink while sitting in a deck chair.
    After dinner we all grabbed a nap ready for the nights viewing ahead. It was great not having to set up the scope every night - once set up the first night we just covered everything and then added power when we wanted to resume viewing.

    The second night was not quite as pristine as the first, but still pretty good. We were joined by our new astro pals we had met at breakfast the previous morning. Nancy, Catherine and Scott were from Olympia and although they did not have scopes they shared our love of the sky. They had many stories of star gazing all over the US. The spent lots of time at our scopes and it was great fun sharing our favourite objects with them. We observed until about 2.00 am by which point some clouds had rolled in and it turned quite chilly. We planned to take the van down in to Ellensburgh tomorrow (Friday) so I was quite happy to hit the Van (hit the sack) earlyish tonight.
    Next day by about 10.30 we were ready to take the mountain road downhill for the first time. It was really no problem at all - although I couldn't figure out how to engage the van's manual override to its automatic transmission. By the time we were on the lower road I could smell the breaks burning - that's the moment I figured the override had been working I just hadn't nudged it into a low enough gear to feel it. It was an open run into Ellensburgh through some dry deserted looking farmland. About 10 miles later we rolled onto main street of the very attractive small town. The town has a population of 15,000 with 8,000 of those being students. That lunch time they all seemed to be in McDonalds! I've never seen so many people serving or so many customers in the one McDonalds! Dan spent about an hour on the phone to India trying to put money on his US Special Phone. We enjoyed an air conditioned lunch. We then headed over to Fred Meyers, the big (Walmartish) store in town. Actually the town has a ton of stores, gas stations, motels, etc. Our coolers were out of ice and both had about 4 inches of water in them. Scott had told us he buys dry ice in the US and so we asked at the store. When it evaporates it turn directly into CO2 (Carbon Dioxide) so there is no water or mess. The store supervisor told us not to handle it then fished in a big bunker with protective gloves on and put a couple of bags in our coolers. It worked a treat and its advertised to be 5 times more effective than water ice.
    While in Fred Meyers there was a sudden roar - the lights flickered and we looked outside to see a ferocious hail storm raniing down. It was hailing at 25 C. When we got back outside the temerature had dropped a few degrees but it was still over 20 C. We headed back up the mountain hoping the road hadn't been snowed on. It hadn't but we heard tales of hail the size of golf balls raining down on the camp site. We had covered most of our equipment and the rest was in the sun tent. It did get wet but it was all in cases, so no harm done. It had turned very chilly on the mountain though. Most people donned ski jackets and we got into the van to warm up. It was pretty cool watching the mountain 'weather machine' in action - clouds were spilling down onto the open field in front of us, while much higher up the sky was blue.

    That night it was full winter weather gear including ski pants, touques and gloves. The air was very moist though and within 15 minutes of putting up the SCT the corrector plate was completely fogged. I hadn't put the anti-dew strip on and now it was too late. I switched to The AR152 Refractor. Our regular visitors Nancy, Catherine and Scott arrived and we had a mini-party - swilling tea, chips (that's crisps), pepperoni sticks and other miscellanous snacks. We toured through Cygnus: The Dumbell Nebula, The Coathanger, The Veil; Cygnus: The Ring Nebula, The Double Double: Hercules; M13 and M92: then down to Sagittarius and Scorpio: M22, M17 and Antares. Scorpio was higher than we normally see it at home and I could actually see for the first time the entire shape of the Scorpion. I guess this was due to our more southerly latitude (about 350 miles farther south) and our altitude of 6,500 feet.
    As the night went on I began to lose the battle with the dew - my eyepices, finder, red dots were all fogged and dripping. I employed some blue small (car towels) I had thrown in the van to wipe my eyepices and finder with. Normally I would never dream of doing this but I didn not want to be denied the views under a dark sky. I threw in the towel - litterally - at around 2.30 am and hit the van (hit the sack). Next morning was warmer and we were back to shorts and sandals and about 23 C by 10 am. We made some breakfast and then headed around to the scope vendors. Dan was eyeing a Celestron Ultima LX 32mm 2" EP. He had tried mine quite a few times and thought this would be a good match for his 13" DOB. I bought the 22 mm version to bring my collection within one of the full set. We returned an hour later and Debra picked up the 17mm version. I came back later and picked up a couple of Celestron Star Maps and an OIII Filter. The prices were very good and the EP's were going for $125 US. including tax. I had payed $150 US plus tax and shipping for my 32 mm LX about a year before.
    It was out of the ordinary to buy astronomy gear and get to use it all the same night. That's what we did!
    The final night was Saturday and it was back to excellent conditions - about 10 C and dry. Debra embarked on the NGC Challenge but had trouble because she did not have star maps showing many of the challenge objects. She ventured round to the main scope field where some observers had volunteered to assist others with the NGC Challenge. I had great views of Saturn early on in a blue sky and then some good deep sky too. It was in the back of my mind that I had a 350 mile drive back up to the border next day, so I decided I did not want to do it on 4 hours sleep.
    I headed to bed around 2.30 am weill satisfied with my last night at Table Mountain.
    Next morning there was no mass exodus, people took their time, most staying around for breakfast, and by the time we were ready to leave around 11.00am there were still many RV's and campers preparing for lunch and going walks to the mountain lookout points.
    I knew I would love the Astronomy but was not sure if all the packing and camping (ish) would be worth it - it was!
    I will be back next year for more and am looking to the next local star party.






  4. James4
    The RASC here in Canada put together a web page showing highlights of everyone's efforts - all across the country - to see the 2012 Transit of Venus. My own blog is included there (with the transit cake).
    http://rasc.ca/transit-2012-results
    It's the first event I can remember where it seems everyone was observing the same thing at the same time from coast to coast. I have to mention that it seems like the whole country got to see the transit except BC which is normally the shangrila of good weather! When does Mercury next transit?
  5. James4
    Leading up to The Transit of Venus - billed as the biggest event in Astronomy, there had been much discussion in the club about publicity. Some people said 'we need TV, Newspapers, Radio, massive publicity -lets get everyone down there for the greatest show on Earth. I instantly flinched, picturing hoardes of excited visitors under a rain soaked 'Greatest Show on Earth' banner. OK got to stay positive but realistic I thought. Somewhere in between 'American Idol' and a one line ad in the paper is what we need. We did put up posters and there was mention of the event in the local papers. We had already missed the Lunar Eclipse earlier this year - turning up at oceanside at 3 am to total cloud cover. Then May 20th for the 74% eclipse of The Sun where I had actually handed out eclipse glasses to colleagues at work - and we had some minor publicity - and Rain!

    But think positive, we live on The Sunshine Coast - people move here everyday from -40 degree Montreal to +10 degree Vancouver (nearby). Its June 5th, its almost summer - what are the chances of bad weather ...
    June 5th - Took the day off work, got up at 9 am. Raining ... bad start, but it could brighten up, there is the whole day to go yet. Went for lunch and was sitting in the car eating my chicken strips when up through the sun roof I noticed the Sun almost poking through the clouds.

    I checked my watch, 2.20 pm - The Transit was due to start at 3 pm. I headed down the highway back to Davis Bay - better get setup I thought, if the sun is visible for just a few minutes I want to be ready for it. As I headed from Gibsons to Sechelt I kept glancing up through the sun roof at the cloud shrouded sun. When I arrive at Davis Bay where the club was meeting, several club members were there already - standing around talking. The sun had shrunk back into the clouds though. I had a secret weapon though to keep my spirits up. The day before I had bought some of those yellow lense sun glasses that block UV and are good in low light. They instantly make a dull day look like the sun is shining.
    A couple of members disappeared within minutes, and never came back. My theory is they panicked and decided they would have a better chance somewhere else within driving range.
    The TV Crew arrived - what? Who called them? I had setup my scope - an Explore Scientific 152mm Refractor with Thousand Oaks Glass Solar Filter on a Sky-Tee Mount. The TV Camera pointed my way (oh no, not me again) and the reporter said "I just want to ask you a few questions about the club and the event that's happening here today" - OK if you must ...
    I blabbered on about Captain Cook, safe solar filters and the club glancing up at the sky from time to time.
    The clock marched on - then about 4 pm, I glanced up and saw the sun skimming through the thin cloud. "There it is!" I shouted, everyone donned their solar glasses and strained to see the solar disk. But it was not strong enough to be seen through the thin cloud layers ... I looked up and even briefly stared (mustn't stare ...) at the cloud dimmed sun - I hoped my UV blocking glasses protect me. Also I had read if you can look at the sun comfortably - eg through fog, mist etc, then it was relatively safe to look. Don't quote me! I clearly saw the solar disk, but there was too much cloud shrouding the sun to see the dark shape of Venus. Then for another few seconds the sun did split the cloud and we donned our solar glasses again. THis time we did glimpse the disk at full intensity - but only for about 10 seconds before it faded below the glasses threshold again.
    My cell phone rang and it was my astro pal - Ed who had split town for Tofino on the west coast of Vancouver Island - the only place with a clear forecast. Ed said he arrived just before first contact, had setup and was filming the whole thing! well done Ed we said. We signed off and saw that to the west at least blue sky was visible.
    As the afternoon wore on, the blue sky came nearer and nearer but by 8 pm the trend reversed and I think we all realised were were going to be shut out after all.
    On the plus side, many visitors talked with us about Astronomy, the club, the transit, and about Telescopes.
    Those of us that hung out until the last chance, packed up at 9.20 pm.
    Next day on TV, Sunshine Coast Magazine came on and there we are (there I am blabbing) talking about the transit.
    Then while we had been blabbing the reporter had turned her TV Camera skyward to the sun skimming through the thin cloud and whoa -there it was - the dark marble of Venus about mid-way across the solar disk. She had filmed what we just couldn't see ... Amazing!
    The way I see it - If I had just stayed in bed and The Transit had appeared I would have been kicking myself for the next 105 years. But I was there - ready - and gave it my best shot. There's nothing more I could have done to make it happen, so I can rest easy. It was after all a good day - lots of pals - lots of scope talk - a Transit Cake and a few
    'almost' moments.

  6. James4
    I was up at the airport with several club members Saturday night and we lucked out with the best clear skies of the year.


    I enjoyed views of the crescent moon slowly sinking in the west, while Saturn rose into good position. I shot a few frames with the DSLR and wondered how many moons I could pick up with the camera.

    I also got a chance to compare my budget minded Celestron UHC Filter 2" with my Neil's 2" Lumicon UHC. The Lumicon sells for $200 while the Celestron is $100 so wondered just how useful it would be.

    We settled on M27 the Dumbell as a good test subject and we were able to easily 'A' 'B' them by holding them against my 2" Celestron Ultima LX 32mm eyepiece.
    The Dumbell Nebula was very visible without a filter but the sky was noticabely light. We tried the Lumicon first. M27 was definately fuller - just more nebula round the outside. The sky was much darker with field stars dimming to about half their magnitude.
    Then the Celestron UHC (also billed as a Light Pollution Reduction filter). The sky was brighter than with the Lumicon, but M27 was still better then without.

    We tried to find the Veil but unfiltered I just could not see it. With the Lumicon, The Witches Broom section was faintly visible appearing as a faint smoke trail. I switched to The Celestron, but could not see any sign of it. OIII is certainly the filter of choice for The Veil, and previously I had been blown away by the effect of an Orion OIII on The Veil. The sky was not as dark tonight and the UHC certainly was much less effective under these conditions.
    So thinking it over - I think $100 is just about worth the price to see the improvement I did on M27. I need to look at more objects with the filter to decide how much of an all rounder it is. If I could source Lumicon's (OIII and UHC) at $150 I would buy them instead. But at $100 I think this Celestron version (comes in a Baader case) is good value if your budget is constrained.
  7. James4
    It was third Friday of the month and that is Astro-Cafe night at Davis Bay by the ocean.
    After tea, coffee and hot chocolate, I was eager to get the scope setup.
    I left a half dozen members in the coffee shop while I drove round to the South end of the Seawall and began setting up the Scope.
    I had the Celestron C9.25 and the Alt/Az T-Mount. Without motors and power it was quite quick to set up. I pushed the scope to Venus and found a really nice view. The 9.25 has a long focal length 2305 mm which makes 180x with a 13mm eyepiece. Immediately a couple of passersby enquired what I was looking at. I invited them to have a look. They turned out to be Jack and Doreen and they were really interested to here my ramblings about Venus being thought to be our sister planet with lush vegetation and Venusian cities etc ... until Russian probe after Russian probe forgot to phone home - because they were crushed by the lovely Venusian atmosphere ...

    Venus is a billiant crescent but a little devoid in features - hence I felt compelled to continue my ramblings on Venus into the realm of Gallileo and him realising that the phases he observed through his new fangled telescope could only mean that the Earth was not the centre of the Solar System. Amazingly Jack and Doreen continued to enjoy the view through the scope.
    I moved onto Mars before they left as I wanted them to see The Red Planet. I used less power this time to avoid Mars moving across the FOV too quickly. We could not see any surface detail at 72x but Mars looked pretty amazing with its particular colour with dark sky around it and some field stars framing it nicely.

    Around 10 pm the rest of the Astro-Cafe crew arrived. Debra setup her 10" Astro-Tech Newtonian (Dob). Ed arrived then too and wanted to have a look for the recent Supernova in M95. Yikes I thought, my GoTo is at home and this is only my 3rd time out with the Alt/Az T-Mount.
    We broke out our star maps and found M95 in a small flock (yes flock) of galaxies. How are we going to pick M95 out of this group. I went pointed roughly to 53 Leonis - since it was visible naked eye and then I just drifted up and left until I wandered into a galaxy field. I was using a 32mm 2" and despite the street lights, and traffic lights the moonless sky showed the galaxies well.
    After mistaking M96 for M95 I then noticed the small triangle of stars near M95 and thought that's the one!
    Ed and Debra concurred on the 10" Newtonian - we then proceede to debate which star was the Supernova - could we even still see it. Turns out Yes. I could see it above the cloud of M95 and when I checked in the 10" I saw it below the cloud which was a good cross check since the SCT and Newtonian present different views.

    At first it needed averted vision to see the star away from the galaxy core - but after a while it could be seen almost directly.
    Later we went to Saturn and it was a really nice view. I gradually saw one, then two, then three, and finally four moons - my first Saturnian view with the SCT. Just then a super bright flashing LED light came along the road. We all looked up to see what kind of vehicle this was. Turns out it was Bruno on his way home from work on this bike, with his little dog safely in a box like min-housing on the back of his bike. He saw our scope and doubled back to have a look. I showed him saturn and four moons - woohoo! Another great moment in Astronomy!
    At 12.10 pm my 5am rise began to catch up with me and I began to dismantle the rig.
    A good first 'almost summer' Astro-Cafe.
  8. James4
    Came back from my regular Saturday outing yesterday and decided to get the scope out for some solar observing. I have not done a lot of solar observing but I really like the casual nature of it. No need to worry about lights, or cold and no need to wear ski pants!

    I used The Explore Scientific 152mm Refractor with Thousand Oaks Glass Solar Filter. At first I thought wow - there is nothing here ... Just the Solar Disk.
    After about 20 seconds a small group of spots came into view in the lower right quarter of the sun. I boosted power to 60x (the sketch notes are incorrect - I was thinking about the SCT FL) and then found a nice detailed view of this little complex consisting of one major spot and several mini spots. I did shoot video but had real trouble seeing the spots in the LCD Screen - so I decided to sketch instead.
    I put together a time lapse video here (on YouTube) of a solar observing session on the driveway. The images were taken every 20 seconds on my DSLR which was setup on a tripod.

  9. James4
    While I was awaiting delivery of a new CGEM, I made the mistake of visiting the new scope shope that opened up within lunch time driving range of work. I immediately noticed an large wooden tripod with Alt-Az T-Mount atop.
    I've been looking out for a large Alt-Az mount for some time - for those nights when you don't intend to stay out too long. I wanted one capable of supporting a 152mm Refractor or the 9.25 inch SCT.
    A strange thing happens when visiting the scope shop - I call it 'Scope Shop Psychosis'! The bank manager in my head seems to take a lunch break and suddenly I'm looking at binoculars at $199 and thinking - wow look at that, just $199 - yeah I'll have three of them!
    In this case though it was the T-Mount. I made a quick decision (before the bank manager came back from lunch) and said yes please, I'll have one.
    The stated load capacity is 15kg each side. Both my scopes weigh around 22 lbs without accessories. I setup the wooden tripod on the driveway and brought out the C9.25. It looked like it would be awkward to attach the scope to the Vixen Style saddle plate. But I found the best technique was to bear hug the scope and tip it into the wide open plate - then crank it down fast.

    It felt odd pushing the 9.25 around without any counterweight attached. But the mount was quite stable. There is a small counter weight shaft on one siide and I purchased the small 7 lb mini-weight. This is really meant for the scope on that side which means it can move somewhat independantly. But I attached it and unlocked that side so that it would point down.
    Moving the mount around felt odd but worked well. The motions were very smooth and I was using 180x on Venus and Mars. If you balance the scope carefully you can leave the locks off and just push it around. I had the scope a little front heavy and used the push to target, lock the clutches and then use the slow motion controls technique.
    The real benefit came during breakdown. After detaching the scope there really was no breakdown - I just lifted the tripod with mount attached inside the garage. You can carefully fit the tripod with mount in a big Orion Scope bag and then into the car.

    My driveway is uneven and I found two things happening. When pushing the scope around in Azimuth the tripod had a tendancy to skitter - just a little. Also the wooden legs slowly sank a couple of times - they need to be locked quite hard. But overall I was very pleased with how quickly I can be using scope without cables or power and no counter weight shaft to be attached (I just leave the mini-shaft attached and remove the small weight).
    The tripod extends quite high and with the mount attached it puts the saddle plates at about the same height as my CGEM.
    I did later experiment in the garage and attached the 9.25 SCT on one side and the 152mm Refractor on the other side. It held steady and was able to move around allright. But I've yet to try this in the field.
    All in all I'm pretty happy having this option available now.
  10. James4
    Another outing with the new CGEM - this time in daylight. I had the Explore Scientific AR152 Refractor on board with a Thousand Oaks white light glass solar filter.

    I used 'Quick Align' then slewed to the Sun. You allow The Sun to be displayed on The Planet Menu by going to Utilities and enabling it.
    Although the Glass Solar Filter is not quite as sharp as the Baader Astro Film, I really like the safety aspect of it. It can't rip or blow off in the wind and apparently the glass is quite hardy - scratch resistant etc.
    I just feel better with the Glass Filter.
    I need to remind myself what The Sun looks like as we approach The Transit of Venus on June 5th at 3.00 pm (PST).

    OK changing the subject now.
    Since I got the CGEM I've been looking around for cases. The Refractor came with its own metal case, but I need cases for the C9.25 and The CGEM.
    The prices are disgraceful - I'm just not willing to pay $450 for a case! So I headed over to Walmart with an $100 budget. I was planning on checking out a Stanley 24 Gallon Mobile toolbox - but instead (in true Walmart fashion) I found two 31 gallon toolboxes for $25 each! They are just corrugated plastic. But because of their size they are really quite robust. You can easily sit on them without any problem.

    I used the firm but soft foam that came with the scope and some extra computer foam to basically jam the scope in. This is not a flight case by any means but works great to transport the scope in the car and stop it getting banged around.

    Likewise The CGEM mount. The Mount is really quite heavy and it will do damage to your other gear if left to slide around the back of your car.

    Lets see - instead of 2 cases at $450 = $900 - these cases cost $50 in total - leaving $850 for eyepieces! Yipee!

    Stacked together they make quite a good platform for maps, tea mugs, or to put your accessory cases on top.
    P.S. The Sun was very quite - just one medium sized spot and maybe three very small ones. Should it not be busier?
  11. James4
    Jupiter
    Second time out with the C9.25 and Jupiter served up a surprise. At first look I thought - Oh yes, I'm not falling for that one again - one of those apparent moons must be a star. But no, it was actually the four Gallilean moons in an unusual (what do I know, its cloudy here for 4 months of the year) configuration.

    Crayford Focuser
    I had trouble with vibration when focusing at at 470x (5 mm ep). I need to put a crayford focuser on the back with fine focus control.
    F/6.3 Reducer
    I recently had a C8 and found when using the F/6.3 Reducer I could bring only one of my eyepieces to focus - a skywatcher 42mm. I wanted to try this again with the C9.25 and with my Celestron 32mm, 13mm and 5mm 2" eyepieces. Brilliantly they all came to focus. Than means I can fit the Pleiades and the full extend of
    The Orion Nebula into my field of view.

    I already sent away for a 56mm Erfle to get a wide field. If that focuses with the reducer in place I will be down to 42x and approx 1.2 degree FOV - not bad for a scope with a 2.3 metre focal length.
    Again I tried the UHC filter - this time at low power with my 32mm Ultima LX in place. But it was Negatory on the HorseHead (a real ask that one - but its on my to do list for 2012), the California Nebula and The Rosette. Now I know the Rosette is not that hard (although I have never seen it), I just need a dark sky and no lights shining on me.

    Finally I looked overhead and found a striking view of both M37 - (this normally looks like I'm viewing a cluster of small fine stars from some distance, but this time 180x [13mm ep] put me right up against the cluster which appeared to have slightly blue stars with a redish one in the middle) - and The double cluster. The Double Cluster was superb - the stars were bright points - no sign of collimation issues overhead - perhaps the poor seeing is responsible for my less than impressive Jupiter views after all.
    Looking forward to next time out.
  12. James4
    First light for my Celestron C9.25 was pretty chilly at -2 degrees C.
    It was Thursday night and I had asked for Friday off work in the hopes that the Clear Sky Clock would come through with its promise of clear sky at 9.00pm onwards. Minutes after making this request, the clear blue skies seen from my work desk clouded into a heavy grey shroud. Not kidding - I managed to change the weather pattern from clear to cloudy just by asking for time off for Astronomy! I was not feeling confident that night but I took a look outside at 8.45pm and I saw Orion rising in the East in a fast clearing sky! CSC your are superb!
    I threw the scope up in case the clouds returned.
    I did a quick align (which is no alignment at all) and slewed to Jupiter. I used a 13mm Ultima LX 2" eyepiece for 180x on Jupiter. My first look did not overimpress me - I was expecting great things from the legendary 9.25. But honestly I've struggled to get a satisfying view of the Gas Giant since September. In recent views with a 6" refractor Jupiter has looked colourless and grey. I wondered if The SCT collimation may be a little off.

    Thierry Legault has an excellent SCT collimation guide on line. I tried this and found right away that I needed to dial it in a little. I used Rigel defocussed at 180x to even out the light doughnut. When I went back to Jupiter, even although it was sinking in the West, it had improved - I noticed the moons were more definately spheres - still with some sparkles but not bad.
    I went to 470x (5mm eyepiece) on Rigel and could see the diffraction rings when defocussed but I could also see a river of air blurring past Rigel in an East/West direction. I've never seen such a clear view of unsteady seeing. The image of Rigel was distorting like a flag in the winde - it was much too unsteady to see the airy disk in focus for fine collimation.

    I decided to just enjoy the views as is. At 180x (13mm ep) on Jupiter, I noticed fairly annoying mirror shift. Jupiter moved more than its own diameter across the FOV (field of view). I was alarmed by this - this would be no fun at high power. My previous C8 had almost no mirror shift at all. I decided to rack the focuser all the way out and back in again. This seemed to greatly reduce the problem. A much smaller shift now, I've since ran the focuser fully in and out several times. I decided to think about putting a 2 speed crayfor focuser on the back of the SCT.
    Next I wanted to try my Celestron UHC filter. I slewed to Orion and studied The Orion Nebula at 73x for a few minutes.
    It was not obvious at first but after a few minutes I realised the Orion Nebula cloud was definately bigger than I had seen it before. There was no colour but I was seeing most of the sweeping arms and cloud area inside that. The extra aperture was pulling in some more light.

    I then installed the 2" UHC Filter. There was not an obvious difference -- perhaps a little bit more to the cloud, but I was standing in full glare of the street lights. I hope under dark skies I will notice the improvement I saw some months ago with borrowed filters. They were of higher price (and maybe quality) - a Lumicon versus my Celestron. If I can, I will compare them head to head.
    The Trapezium was an open uneven square at 180x (13mm ep) but I could see the stars were fluctuating in the uneven seeing. After seeing the river of air rushing past the image of Rigel, I realised the scope was probably performing pretty good for the seeing conditions. There was a cool breeze and around 10.30 I ended first light.

  13. James4
    03rd September, 2011
    I was eager to get the new Explore Scientific 6” Refractor under dark skies again. The Sechelt District has recently given us the keys to the Airport and encouraged us to make use of the under used land there. It looked like only Neil and I were going – none else answered our emailed invite. But at the gate 12 members of The Sunshine Coast Astronomy Club turned up.
    I’m always harping on about the lack of people who will come out under a dark sky and see the real universe above our heads . Meanwhile lectures about the universe are packed. However, I realised that 12 members amounts to 33% of our membership!

    We all wanted to see Comet Garradd and so under a still light sky I looked for The Coathanger, below and slightly behind Albireo, the tail star in The Northern Cross (Cygnus). I was surprised the entire Coathanger managed to fit in my field of view. I was using a 2” Celestron 32mm at 31x and calculated this gave me a field just over one degree wide (eyepiece focal length (32) divided by magnification (31) = 1.03 degrees. The coathanger is eyecatching because it looks like someone drew it with a ruler.
    I drifted the scope East looking for anything fuzzy! With the last star in The Coathanger on the edge of my FOV (field of view) I saw a little group of three stars and there above them was the fuzzy snowball I was looking for. Quite unimpressive with the sky still being blue, but who doesn’t want to see a comet? Later it did improve and the hint of a tail was visible. I hadn't aligned for imaging but I grabbed a few frames through the refractor with a Nikon D5000 DSLR.

    Just then a helicopter approached the runway – it suddenly dived low and sped along the runaway no more than 20 feet (if that) above it. When it got to the end it flared up steeply then hovered. Not bad having an aerobatic side show while doing astronomy.
    Jupiter would be up later, but for now we were waiting for it to get fully dark. Finally around 11.00 pm it seemed dark (ish). I had recently seen The Veil Nebula in Dan’s 5” refractor. I was amazed to see this in a 5” scope, I assumed it would need large aperture. I remembered it looking like a flickering ghostly faint cloud. I slewed to The Western Veil’s position and looked . There was the faintest wisp of a cloud near the centre of the FOV – barely visible. I asked Dan to borrow his Oxygen 3 filter (OIII) and threaded it onto the 2” diagonal. I looked again and was amazed to see The Veil.

    When I say ‘see the veil’, I mean I could actually see structure, detail and features. It looked like a large noctilucent cloud. I had never seen The Veil before in any scope of mine.
    Then I thought what about The North America Nebula? I’ve read about it many times and there’s usually always some disclaimer that I translate as meaning ‘don’t even go there sonny jim, unless your David Levy with a 16” scope on a mountain top in Arizona!” But what the heck, I slewed there and with the Oxygen III filter still in place I looked … There it was! I could immediately see The Gulf of Mexico region. I tried to reconcile the shape I was seeing with my recollection of the shape in the star atlas – I wasn’t sure of the scale. But I wandered round the cloud and noted a few stars bordering the nebula.

    I was amazed what this OIII filter could do. And I guess the 6” unobstructed view was ideally suited to this too. At such low power I still had tack sharp stars across the field, this was much different than in my 8” F/4 Newtonian where low powers lead to very blurred stars (becuase of the steeply curved mirror) anywhere off axis.
    Just after that Jupiter broke the horizon. We saw its four moons early while it was still in the trees. But we would have to wait for it to climb clear of the trees to get a good look.

    Nearby I heard David mention Uranus was in the sky. I have looked for Uranus on several occasions and never been sure I was actually looking at it. The last time was with a 10” Dobsonian. I was fairly certain it was one of the objects in the field but was not positive. I couldn’t really say I was seeing a disk, but I did have a greenish looking star. Its worth a look I thought, maybe the refractor view will be different.
    I slewed, I looked, and there it was! A bright light blue (maybe a hint of green) disc slightly fuzzy round the edges. It could not be mistaken for a star. This was also at low power – 31x. David called for me to go up to 200x to test the scope. But the view was so perfect I stayed at low power.

    Neptune was near too, I slewed, I looked, I saw (does this sound like the astronomy equivalent of “he shoots, he scores”?). It too was an obvious planet, but much smaller and not as distinctive as Uranus.

    What other invisible object could I pull from the sky with the use of these seemingly magical filters? The Helix! Yes, one of my all time favourite DSO – only available in magazines normally! I had actually photographed The Helix previously – it took 40 one minute exposures through an 8” SCT. Visually it was not there – just not visible.
    This time Neil offered up his Lumicon UHC (Ultra High Contrast) Filter. I had no idea if this could match the OIII for effectiveness. I slewed to The Helix. I looked and there was empty space. I threaded on the UHC Filter and commented to Dan and Neil, “if I can see The Helix with this – I am buying one whatever the cost!” I looked again and saw a large grey cloud – The Helix!

    I was seeing The Helix Nebula visually for the first time…

    At this point I considered looking for Black Holes, anything seemed possible!

    The clock struck 2.40 am - and just Neil and I remained. We marvelled at how good the sky was. The Pleiades was rising over the trees and Jupiter was climbing higher, but we’d seen what we came for – a clear sky!
  14. James4
    This blog is part observation, part scope comparison, and part equipment test.
    What can I say my time is limited I had to squeeze it all in to one session :)
    All-nighter
    Friday night started poorly - I missed the boat home (I was the last car not to get on). I left work at 4.15pm and finally got home at 9.15pm. So I thought, I'm not losing my Friday night. I decided to pull an all-nighter and finally get Jupiter under a clear sky. I had dinner, took a shower and delayed until Jupiter was high enough. I setup up at 1.00 am.
    Refractor first
    Jupiter was now well up and looked steady to the naked eye. I setup my Celestron CG5-ASGT and Put The Explore Scientific 152mm (Achro') Refractor on the Mount. Jupiter looked nice at 121x so I pushed up to 197x. One of the moons was closing towards Jupiter but I was too busy looking for detail on Jupiter's cloud decks to think ahead. After 30 minutes or so, I realised the close in moon had disappeared and its shadow was now transiting Jupiter.

    I studied the shadow and shortly after it began, I noticed a dark feature in the North Equatorial Belt - I thought it was a double shadow transit.

    Astro-Tech 8" Reflector
    I took the Refractor off the mount and switched to the 8" reflector - I wanted to find which was sharper. I used the same eyepieces on both scopes - a Celestron Ultima LX 5mm 2" - with Antares 1.6x Barlow 2". This gave me 256x on the Astro-Tech and 317x on the Refractor - a significant difference but Jupiter did not offer any less detail down at 200x. First look and surprisingly I could not see the shadow with the 8". Jupiter was steady but show low contrast in both scopes - I think high haze was responible as the stars were dim.
    I moved the focuser back and forth back and forth trying to pull in that dark feature I knew was there - but I could not see it.
    This scope has really good optics - I have seen a perfect diffraction ring pattern around bright stars at high power - and for imaging it is superb. But the oversize secondary (wonderful for photography) is 35% by area and that's enough to reduce contrast visually.

    Fringe Killer
    I switched back to the Refractor and again the shadow transit was visible - I shot lots of video with a pocket digital and snapped many stills with a Nikon DSLR at Prime plus Barlow. The big Achro' was throwing up a strong purple halo around Jupiter - bigger and purpler (is that legal) at 317x than at lower power. I added a Baader Fringe Killer. If I trust any company to know what they are doing, its Baader. The fringe was reduced and now appeared more crimson than purple but the view was no sharper than before.
    It was only the second time I had seen Jupiter all year and the first time seeing it high up in the sky. I was a little underwhelmed at how low contrast the view was - I have seen a shadow transit more obvious in a 4" Refractor. But it was great to be under the stars and have an unexpected shadow transit of Io for a scope comparison.
    Summary
    The Refractor - despite the fringing was able to show more detail. Jupiter appeared as though I was looking through haze - so I have no doubt under transparent skies the Astro-Tech would also have shown the transit.

    The Fringe Killer - not effective is all I can say - perhaps the haze reduced its effect? I still want to have the option of using it though - perhaps it will prove itself as I use it more.
    Feel like a got my Friday night back - thanks Jupiter!
  15. James4
    Just wanted to post some information on using the Baader (multi purpose) Coma Corrector on my F4 Astro-Tech 8" Newtonian.
    I've been hearing (from telescope dealers themselves) that some coma correctors do a very poor job of correcting coma in fast Newtonians. Some also increse the focal length and therefore the F Number. For those of us that don't guide, the F Number is king. I don't want to lose the edge that F4 gives me. For this reason I chose the Baader Coma Corrector, as it specifically states it does not increase focal ratio.
    Image 1 is the corner of an image of M31 taken with my F/4 Newtonian without any correction.
    Image 1

    This is the bottom right corner of an image of Andromeda
    You can see the stars around M32 are blurred and
    enlarged.
    Image 2 is a later image of Andromeda with the Coma Corrector in place.
    Image 2

    This is a similar region of a later image of Andromeda.
    This was taken with the same equipment as the
    first photo - but with the coma corrector attached
    to the DSLR
    In Image 2 with the coma corrector in place, not only are the stars in the corner of the frame fully corrected, but some stars are visible in the cloud of M32 which are invisible in the first image. The difference in orientation is due only to the DSLR being oriented differently on the telescope and not to any change in focal length. This coma corrector can be fitted to eyepieces with additional T2 rings. I'm not concerned with this, my requirement is that images are corrected for photography. I therefore leave the corrector attached to my camera's T-ring. I simply fit this assembly to the camera for imaging.
    I bought this corrector new for $149 USD. A good deal in my opinion.
    Thanks for reading.
  16. James4
    CG5 All Star Software Polar Alignment
    I have always used a Polar Scope to set up equatorial mounts for imaging. When I heard about
    Software Assisted Polar Alignment I was skeptical. I was skeptical because during star alignment I have often found
    alignment stars to be fairly off centre and occasionally outside the field of view. However this was happening
    with my C8 partly due to having to rotate the 2" Diagonal every time the OTA moved to a new star.
    When I rotated the Diagonal, the star would shift noticeably in the Field Of View.
    After upgrading my Hand Controller to Version 4.16, I decided to give the new All-Star Polar Alignment a try.
    I performed a 2 star alignment with 1 Calibration star. The stars were Sirius, Procyon, Rigel. Procyon was the calibration
    star and I was pointed at Procyon when I initiated the Polar Align Routine. The routine is now accessed by pressing
    The Align Button on the hand controller. The hand controller prompted me to centre Procyon in the eyepiece then press Align.
    I did and the scope then re slewed to Procyon. But this second slew moved the scope to where Procyon should be if the mount
    were accurately polar aligned. Now I moved the scope back to Procyon by using only the Altitude and Azimuth adjustment knobs on the mount. Its best if you put the hand controller down during this phase - the temptation is too great to tap the direction buttons as you normally do when aligning on stars.
    I had initially used the polar scope to put Polaris in the centre of the Polar Scope. This way I knew my alignment was already close so there should not be any large correction required. When the scope re slewed to Procyon, it was off target by at least as much as two moon widths. I scoffed at this and thought the calculation must be way off. But I thought I would complete the test anyway.
    I gradually moved the scope back on to Procyon using the mount adjustment knobs. This took around 5 minutes. I took off
    the Polar Scope cover and looked for Polaris. I did not expect to find it in the field of view. But in fact it was positioned
    just outside the small circle for Polaris in the Polar Scope. I was surprised at this mainly because it seemed I had moved the
    telescope a lot to align on Procyon. I looked at the orientation of Cassiopeia in the sky and compared with the Polar Scope
    and realized if I rotated the mount to match the sky view - Polaris would indeed be inside the small circle.
    From this I realized the Polar Scope has a much wider field of view than I expected. This means in turn that any error in
    placing polaris using the Polar Scope is much larger than it appears. The opposite is also true, that the main scope has a
    much narrower field and therefore potentially a much higher accuracy in placing Polaris.
    I did then take some images and found tracking to be good. My timer had a low power malfunction and set all my exposures
    to 30 sec instead of the 60 sec I had programmed. I was therefore not able to compare directly with previous longer image
    runs. Out of 40 images though, 38 were un trailed at 800mm and 30 seconds.
    This test has caused me to reverse my opinion on this one. I had been confident the Polar Scope would be more
    accurate. But now having seen how wide the FOV is in the Polar Scope it should be possible to easily improve on
    this by carefully using the SW Polar Alignment.
  17. James4

    The Hunt for Sirius B

    By James4,

    I'd just like to point out that Stargazers Lounge is solely responsible for me deciding last week, after 5 years of ignoring 'Stars' and treating them like sign-posts to everything else, that wait a minute, there may be something interesting about them after all. The thread on Sirius B - soon launched me out the door onto the driveway to have a look for the impossibly tricky double that is Sirius and Sirius B.
    Here's what happened:
    I setup my 8" Astro-Tech AT8In on CG5 ASGT Mount on the driveway. This is an F/4 scope and so certainly is not the ideal tool for double star splitting. Probably the 8" SCT with its longer focla length would make sense. But the AT8IN is 'the new scope on the block' and wowed me with its light gathering abilites compared with the C8, so I decided to try it out.
    I began by slewing to Rigel which also has a close companion, with almost the same separation as Sirius from Sirius B. However, Rigel and its companion are not as widely separated in magnitude and this is a much easier double to observe.
    I had a couple of other goals tonight. One was to try the CG5's Software Polar Alignment for the first time. Up until now, I've always used a polar scope. I also wanted to test the Baader Coma Corrector for the 8" Newtonian.

    I did a 2 star alignment followed by 2 calibration stars, then selected 'Polar Align' from the menu (my version of the Hand Controller was 4.13). Half way through my second star aligment the power failed! I restarted and decided to pick 'last alignment'. This worked find and I slewed to Rigel.
    I found the Rigel pair fairly easy to split after a few minutes. But it could be missed if you are not aware it has a companion star. As I aligned the scope I checked for doubles on a few other stars - noting Polaris' quite faint companion well separated from it.
    Sirius was now approaching the Meridian (the East/West border) due South and so was moving towards its highest and best position for observation. Even so it would not climb above about 35 degrees in altitude.
    I used a 4.3mm W70 Antares eyepiece for 186x on my 800mm FL 8" Newtonian - this worked well for Rigel. For Sirius I doubled this up to 372x. Sirius at first sparkled then later was a little muted by the thin cloud that was affecting its appearance on and off.
    I was not seeing Sirius B and had intentionally not looked up its position so as not to cloud my judgement on detecting it. About 40 minutes into observing, for just a few seconds, a fleck of light persisted very close to Sirius. I moved my eye position around to try to confirm it. But after about only 5 seconds it was gone.
    There were numerous annoying reflections in the eyepiece which had to be discounted. I cannot blame the eyepiece for this, as a very bright street light bores almost directly down the scope tube when I'm looking South. Despite an OTA that extends well in front of the focuser and a 2 foot long Dew Shield, the light still spills well into the scope tube.
    The CG5 had tracked Sirius well past the meridian and the motor housings were close to touching. I broke off the pursuit for now. I attached the camera - a Nikon D5000 - and took a few test images of The Pleiades to check for star quality.
    I then went back, first to Rigel and then Sirius, to see if I could pick up the elusive Sirius B on my DSLR. After that I took another 20 minutes using 372x (a 4.3mm eyepiece with 2x Barlow) on Sirius to try to split its companion. I made a drawing of the position of another possible candidate that seemed to be flitting in and out of view just above a diffraction spike, but later after working out its position angle, I ruled it out.

    Below:
    Rigel with its companion hiding in the lower diffraction spike. About 20 minutes earlier it was easier to see visually because of cloud movement.

    Below:
    Sirius and Yes, Sirius B, at the 10 O'clock position. The white halo is a result of thin high cloud which kept chaing the appearance of Sirius during observation.


    Below:
    Sirius and Sirius B (again at 10 O'clock). I confirmed the star field and Sirius B's position with an image from Tuscon-Skies.

    These images were all taken at prime focus (800mm FL) with a Nikon D5000 DSLR - exposure on Sirius was 10 seconds at ISO 3200.
    An enjoyable challenge. Although I did not see Sirius B visually, I was pleased to photograph the elusive 'Pup' as its called. Also having knowlege of its appearance I think will make it just a shade easier to detect visually under more transparent skies. A good 2 1/2 hours under the starry skies instead of in front of the TV!


    The crescent Moon and some high thin cloud were lighting up the sky. On the ground I had a Victorian 'full radiation' street light, and several unshielded neigbhours lights bearing down on me.
    The best defense turned out to be a fur hood! I flipped this over my head and the eyepiece while observing.


    Above: Orion, Taurus and The Pleiades above the scope. Sirius is above the EZ Finder to the left. It was -1 C and ice formed on the scope and camera gear.
    I look forward to trying again for a visual observation of Sirius B when the skies are more transparent!
    The SW Polar Alignment was fine for visual, but not good enough for photograhy. To be fair I did not take much time over it. Adding more alignment stars should improve its accuracy. I will try it again to decide if I can beat the accuracy of aligning with the polar scope. I would sure welcome not having to crawl around on the ground under the polar scope. Its well worth perfecting so I will try a few ideas on refining it.
    The Baader Coma Corrector - not sure as there was drifting on my images. But the star shapes are nice and round. I will also have to try this again to decide if the image has improved.
    Clear skies!

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