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cwis

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  1. cwis
    Bit of a delay in posting this - I'm serious considering whether or not to continue with the blog as I feel a bit conspicuous doing it!
    Never mind. 
    I'm sure very few in the UK missed the clear skies over the past few days....
    Got outside about 2130 - the dob had been out there a couple of hours with dust caps on cooling.  It was cold and dry and still. No dew on grass or 'scope - weird.
    Moon:
    Peeking outside just before I went out there I'd accused LSW (Long Suffering Wife) of leaving a light on somewhere - we rig the house for darkness at the back if I'm going to be observing as the kitchen and bathroom lights in particular light up the back garden like it's daylight. LSW protested her innocence - it was a VERY bright moon.
    So I looked at the moon. I've never really properly looked before - I think I pointed my first telescope at it a few times but never the dob. Crikey. It moves FAST and is so bright. I didn't use a moon filter as I wanted the bright moon to stop down my eye a bit and remove astigmatism and this seemed to have worked - I ended up with VERY crisp views and noticeably dimmer vision out of the one eye afterwards! I'd checked collimation earlier and found it was bang on - as long as I put the 2 inch to 1.25 inch adapter flat in the focuser (it looked like it had moved a bit - wups!)
    The conditions easily took the 10mm UFF barlowed to give 254x magnification.  One crater stood out as it was near the terminator - Gassendi. I could clearly see the rilles and tiny hummocks on the crater floor and a small crater about 120 degrees from Gassendi A - according to maps it's about 2-3Km across which is amazing be able to see at something like 385000Km distance.  I did have to blink a number of times to make sure it wasn't a floater.
    Looking away and allowing some night vision back I was amazed how much nebulosity was visible in Orion with the moon so near by. I had a quick peek for E and F in the Trap - both visible (F intermittant) at 127x - E just visible at 70x. I'm guessing the moon was washing F out at lower mags.
    Castor:
    I seem to be revisiting sights I first looked at when I got my first telescope! This was the star that told me I had a problem with collimation as the barlowed 10mm kit eyepiece I received with the 130ps showed a pair of seagulls rather than a double star. This time round a nice pair of almost resolved Airy disks showed at higher magnifications, but the split was obvious at 50x magnification.  I wasn't aware that I may also be able to spot Castor C (I think - anyone confirm?) - something to look out for next time.
    Mintaka:
    I was using Turn Left as a source of easy doubles so I picked off a few in or near Orion.
    Easy split as expected at 50x. The smaller star is supposed to be clearly blue - not to my eyes - perhaps I was still a bit blind from the moon or maybe it's just my yellowed, aging eyes...
    Meissa:
    24mm didn't show the split - a barlowed 18mm did though and moments of calmness showed clear Airy disks and diffraction rings - I so very rarely see them.
    Sirius:
    Bright! Too low in the sky to even attempt a split - the star was a mess of shapes and colours under magnification - it looked like a multicoloured sparkler! I thought I saw glimpses of a dim twinkle to one side of it a few times - it turned out to be a reflection of either my pupil or retina!
    Turned in at 23:15 - didn't feel like I'd actually been out more than a few minutes!
     
     
  2. cwis
    After a couple of months of cloud interspersed with a few short sessions with the ST80 I finally got the chance to drag the 10 inch dob outside. Goodbye tiny pretty pinprick stars, hello big fat fluffy stars but so many, many more of you. Goodbye pleasant soft circular stars towards the periphery, hello scratchy coma!
    04/01/2022
    Clear Outside had been warning me about the possibility of two evenings of clear skies for a few days, so I was READY! I dropped the dob outside on the 4th while it was still light, made sure the power pack was charged for my heated vest, checked collimation (OKish - looks like secondary mirror has moved ever-so-slightly) and got out there for a couple of hours.
    To a large degree I was trying to remember how it all worked - I had a quick look at Orion, toured around the sky and took in the Pleiades (nicely nebulous with the dob - can't make up my mind whether that's my eyes or actually really there!)  but spent most of the session on Andromeda - it was high up so nice and clear (M42 seemed quite wobbly to me at that time) and I wanted to have an extended session to see if I could finally spot M110. I've found M32 easy to spot, even with the ST80, but even with goto, never spotted M110. Also I've managed to seize my drummer's throne height adjuster so higher targets were far more comfortable.
    I finally managed to spot M110 with inverted vision after star hopping using the dob view in Sky Safari to place it in the centre of view in the 24mm (50x) UFF. My mistake was expecting it to be compact like M32 - it's much more diffuse and seems a lot dimmer (Bortle 5). I used my new secret weapon to increase eyepiece contrast ( a black t-shirt draped over my head) Should be easier to spot from now on!
    05/01/2022
    Got outside to a cold dew covered telescope - I like to let it cool slowly with the cover on - seems to attract less dew while it cools. While I was out there the dew on the grass froze  - minus 2 I think.
     
    A slightly better prepared session on the second night with a repaired seat and thermal socks, double Stars bible, observing fluid (Red wine in the summer (gets warmer) and IPA or similar in the winter (happy cold). I only drank the one  - the rest went in the fridge to warm up after the session!) notebook and pen!

    UFF Whitterings with added astigmatism:
    I started about 1930 and initially the seeing didn't look that good - I started at the Trapezium and they were moving about a fair bit - the E star was occasionally visible at 50x (24mm UFF).  It actually felt warmer than the night before because there was no wind and I think the air was less humid - it may already have been below freezing so all the moisture was probably on the grass instead of in the air. With the 18mm UFF (70x) the E was clearer and the F was hinted at. With the 10mm UFF (127x) both E and F were occasionally clear.
    I noticed a smaller zone of sharpness from the 10mm than from the 18mm. I'm not sure whether this is astigmatism or coma etc but I tried the 18mm barlowed (140x) and I think it was slightly better - the zone of sharpness was larger. Or maybe it was a slightly smaller exit pupil working to supress my eye's own astigmatism. I don't know enough to be able to tell - I also find I have to be cautious with eye position with regard to star shapes too - again I'm not sure whether that's my eyes or the eyepieces... My prescription seems to be in flux at the moment (aging eyes) so maybe I need specs with smaller exit pupils now - time will tell.
    I'm pleased the Svbony UFF eyepieces barlow nicely (if you're careful with eye relief) - the 24mm Altair did so I had high hopes... I may pick up the 15mm to complete the set.
    The 10mm doesn't seem quite as good as the other two UFF designs in the sharpness zone size - nice and contrasty though.  Barlowing the 10mm pushed the seeing a bit too far (254x) most of the time but when the conditions momentarily played ball both E and F showed up as nice discrete tiny dots. 
    Plenty of doubles in and near M42 so while I was there....
    Zeta Orionis:
    Blue Blue double easily split at 50x. I had to check with Sky Safari in dob view as I expected it to be harder - perhaps my collimation was better than I thought? Or perhaps the secret contrast weapon is helping? 
    Struve 790:
    A single finder's diameter from the above. Yellow Blue pair of roughly the same apparent magnitude - a wide split even at 50x.
    Theta2 Orionis:
    This looks like a mini Orion's belt! I had no idea they were gravitationally bound. Also in view were S490B and V1073 with pleasant contrasting colours. With lower magnifications I can't help glancing to see if Trap E is visible - distracting!
    Struve 747 and Iota Orionis:
    This was my favourite view of the night - at 50x you can see the trapezium (Theta), Theta2, Iota Orionis or Hatysa and Struve 747.  Struve 747 is a nice bright white white widely split double.  Hatysa is my favourite type of double - closely separated and different apparent magnitudes so it looks like the smaller star is peeking out from behind the larger. I liked the view so much I stepped onto the top of a very long and slippery slope and..
    Took a photo. Help!

    Rigel:
    Like Iota Orionis and Polaris my fave type of double - a nice bright primary and a shy secondary peeping out.  I found out Rigel was a double last year the first night I pointed the dob at Orion. I'd looked at the Trap, meh with so so seeing and decided to try the UFF24mm barlowed and picked Rigel as a close bright target.
    I saw a sharply defined star and diffraction rings and a tiny perfect second dot.  The seeing and transparency were amazing - the campfire smoke had blown aside and the running water I was used to looking through was still. I turned back to the Trap and saw 4x sharp stars with diffraction rings and E and F as perfect little bright dots.  It was like that for a few seconds and then the seeing went back to normal - the wobbles poured back, the stars dimmed down.. Amazing while it lasted though!
    This year at 50x the secondary was almost lost in a diffraction spike but easily discernible. At 70x it was slightly more obvious but both the primary and secondary were dancing about. One day that seeing will return.....
    I came in about 2145 with a flat battery on my phone thanks to the cold and SkySafari and another one on my heated vest. I thought the thermal socks had been rubbish until I started bringing the kit in and noticed the crunchy frozen grass!
     
  3. cwis
    After a frankly disappointing session with my ST80 a couple of days ago I put the question to the SGL hivemind:
    I received a LOT of helpful advice (lose the contrast booster filter!) and some suggested targets to try and gain some appreciation for the poor maligned thing. As last night was promising to be mostly clear I scribbled a target list down from the suggestions and grabbed the 'scope and went outside about 2130. I synced the AZGti with SkySafari for ease of use and began straight away - no cooldown time at all (a novelty!) I only took one eyepiece with me initially - my 24mm UFF.
    Stock 2: 
    Straight away I could see the difference that removing the filter had made. St2 was a scatter of tiny pinpricks of stars, interspersed by larger brighter ones.   Also in the same view was Struve 26 (Skysafari identified it as HD14172 and a bit of web cross referencing showed the Struve catalog ref) a lovely and obvious widely split double.  
    I observed the vista for quite some time getting my head around the tiny, tiny sharp stars being shown by the ST80. Many more than in any binocular view (and my arms weren't shaking) and all so sharp... More stars popped out as my eyes acclimatised and the impression of depth grew.
    Kemble's Cascade:
    This was just a name to me when I typed it into the seach bar on SkySafari (I didn't look up any of the targets in advance)  and my notes read "Near vertical line of bright stars leading to NGC1502 (thanks SkySafari for the id.), with a dusting of dimmer stars visible to the LHS of the asterism. Wish I had darker skies".  
    NGC1502:
    Tiny pretty open cluster. Two closely located bright stars visible instantly with a scattering of dimmer stars getting more numerous the longer you look.  Wiki says there are 45 - I'll have to have a count next time!
    This next one wasn't on the list of advised targets but should have been - it did it for me. Wow!
    Double Cluster:
    This looked at first glance like a very large single circular open cluster bisected diagonally by a dark line of lower star density.  As I looked longer the two clusters kind of resolved themselves as separate - difficult to explain! A truly amazing sight with hundreds of tiny pinprick stars visible and the two clusters together nearly filling the view at 17x magnification.
    I decided to revisit Andromeda without the contrast booster and could easily see M32 - still haven't located M110 even with goto assistance.
    NGC752:
    Gatekeeper stars 56 And and HR556 show the way to this delicate roughly circular open cluster. Again a feeling of depth started to occur as more stars were resolved as I observed longer...
    M103:
    I revisited this target again now I'd removed the contrast booster. Navi was visible in the same view and the cluster was very small, but different star colours were visible... Excellent!
    At this point I thought I'd test the kit a bit and pointed at Capella - a nice bright star. At 17x magnification I could see a horizontal diffraction spike I'd not noticed before. I tried to compare the view without the diagonal but I don't have sufficient focus travel. 
    At 50x magnification (42-8mm zoom) I could see vertical and horizontal diffraction spikes along with a smattering of CA and what I think was atmospheric refraction (blue on one side and red the other)- or maybe colour wedge? Maybe I need to settle the objectives as suggested. Capella was 32 degrees above the horizon at the time.
    I thought I'd try and split Polaris and this time found the secondary - I think it was hiding before in a diffraction spike. Tilting the diagonal brought it out but it was very faint.
    NGC188:
    I've completely failed to find this a number of times star hopping with the dob. While I was here in the region of the sky with Goto I thought I'd have a look. I matched up the marker stars against SkySafari and I could see a very few of the brighter stars in the cluster. I'll have to return with the dob now the position is clearer...
    Uranus:
    While I was waiting for the Pleiades to clear the trees I did a goto to Uranus - just to tick it off my list really - I observed Neptune a few weeks ago. I wasn't expecting much, and didn't get much! Just a star in the right place in the view in relation to the background stars...
    Pleiades:
    Now this is more like what I expected from the ST80! Filling the field of view, large bold obviously related stars. Looking white rather than blue but totally captivating. I didn't detect any nebulosity but I don't think I can expect any at this aperture. I'm not sure the neb I've seen with the dob is anything more than the powerful beam of light from the eyepiece lighting up the murk in my eyeball!
    I took a last look at the double cluster before packing up at midnight. Wow! I think I need to get a mirror diagonal...
     
     
  4. cwis
    More than two months after my last session, I managed to get out again for a short time (just over an hour) on M42 and the surrounding area.
    It's the first time this year I've looked at Orion and the first time ever with the ST80 - I didn't have the time last night to get the dob out and let it cool so I grabbed and gonned!
    It was windy and 20% cloud cover when I went out, so I didn't have great expectations as to transparency or seeing but with the low magnifications of the ST80 this is less of an issue anyway. It was 4 degrees so fairly chilly.
    I was running the AzGti on a new power source - a usb powerpack and a 9V or 12V step up voltage converter  based on the LM2577 chip:

    Maximum load is 800mA for this chip (not sure whether on the 12V or 5V side)  - I did some load tests to check and logged load during my session.
    Here's power utilization with a phone connected to the on board WiFI and the unit tracking:

    And here's the power during a maximum speed two axis movement:

    The usb power meter showed peak current was 650mA during the session (probably when I leaned on the telescope or something) so it looks like it will be fine. It powered the mount happily for the hour and was still showing 99% battery remaining, which is promising although probably inaccurate but not bad for 20 odd quid all in.
    I'm going to 3D print a holder for the battery so it slots into the battery compartment of the AzGti so the unit is completely self contained. 
    During the session I used the following eyepieces, the two middle ones being new UFF ones by SVbony from Amazon I got during Black Friday - I got these because I liked the Altair UFF 24mm so much:

    Initial impressions (I'm neither experienced enough or knowledgeable enough for a review!) are that the 18mm in particular is very much more of the same - lovely sharp stars across lots of the field that soften progressively towards the edge with the ST80 (curved field?) with loads of contrast.
    The 10mm seemed to have a smaller sharp spot, but a similar amount of contrast - it darkened the sky over London nicely to allow the nebulosity of M42 to show up far more clearly than through the 24mm or the 18mm and the teeny, tiny trapezium (at 40x magnification) shone out beautifully.  
    All three eyepieces are fairly picky when it comes to eye position being central, and I noticed a few times it was easy to get under the eye relief of the 18mm in the same way as the 24mm so it takes a bit of practice to see the field stop consistently - less so with the 10mm. None of the eyepieces are parfocal to me.
    Overall I'm really pleased - I hope the 18mm and 10mm barlow as well as the 24mm (didn't get a chance to test last night) and work well in my dob - I'm on the way to being able to retire my cheapy zoom! Seriously temped to get a better barlow (any recommendations?) and the 15mm Altair model would be after that to give me 24, 18, 15, 12, 10, 9, 7.5, 5 and 4 with my Nirvana. I'd only really want a 6mm then probably?
    On to the last new bit of kit (to me!) an old black t-shirt. I used it as a shroud to see how I would get on with a proper one.  I liked it but I'd need a thicker one (I could see light through the fabric which was distracting) . One unexpected upside was that it was lovely and warm in there, and my 4mm Nirvana that I normally avoid using as it mists up so readily steadfastly refused to mist up! I used it to chase the E and F stars of the Trap - no luck on either but the nebulosity showed up really well under the shroud even at 100x magnification.  Not sure whether to make my own or buy one.
    So a short, packed session on just one target - lots to take in and think about for the future and quite frankly it was great to get out there again, however fleetingly! 
     
     
     
     
     
  5. cwis
    Three whole weeks since the last proper session due to holidays, offspring and clouds!
    Managed to get out sometime a few weeks ago to test this:

    It's a 130mm F7 newt built with an SvBony metal focuser, some mirrors from Astroboot, a plastic duct pipe and some 3D printed adapters hot glued in.  I've already got a 130mm F5 newt but I wanted to be able to understand the difference that a smaller primary obstruction and a longer focal length makes to viewing, particularly with regard to planets.  I printed the above very dodgy tube rings and dovetail to take advantage of the last clear day we had a few weeks ago and mounted  it on my AZGTI where it swayed, precariously:

    I managed about 15 minutes with it on Jupiter to check it was all OK after collimation and could easily see bands etc and plenty of contrast, approaching what I get with the 10 inch dob even with the mount wobbling about so very promising! I'll build it into a dob mount I think as it's pretty heavy and this is supposed to be a budget project...
    I also tried my ST80 on a terrestrial target while on hols and was amazed by how little magnification you can get away with:
     
    In the distance out to sea behind the small human experiencing the beach for the first time is a ship called the Sea Puma:

    It was 8.4 Nautical miles away and I could clearly read the name on the bows with 50x magnification, but contrast was very low because of the 15.5Km of soup I was looking  through. - it was looking through fog!
    And on to last night!
    Got the 10inch dob out about 2200 and let it cool for 30 mins - temperature was around 10 degrees C and it was quite windy - wore the winter coat! 
    Started with Polaris to check seeing and collimation - 'scope was fine, sky looked transparent but quite turbulent.  I decided to take advantage of the time before the moon rose above the trees to look at Andromeda as it's the first time it's cleared the trees since I've had the dob!
    The core of Andromeda was VERY bright (24mm UFF so 50x) and M32 was also clearly visible (see bad sketch!) but I couldn't find M110. I wasn't sure whether I could see some Andromeda structure or whether it was the moon lighting up the sky around the core (more likely looking at photos after the fact - M32 is very central) .

    Next on to the Circumpolar sky :- I tried to spot NGC188 as recommended by Turn Left at Orion but I think the sky was too bright as the moon was looming. I decided to spot some doubles:
    Pi1 UMi (HR5829):
    Mental note - when planning these jaunts always look up the targets before the session to get them in a format that SkySafari and I understand so I have a chance of finding them... I still find comparing the diagrams in the book in the dark to the view in the finder very hard so the steer from SS is hugely helpful. I have to state that this is me, not the diagrams - once I'm oriented and have found the target they suddenly make sense!
    Wide clear vertical white/yellow double - obvious even at 50x
    Struve 1694:
    Book says white/white but I see more Blue/while horizontal double. Easily found star hopping. I wonder if my red light is messing up my colour perception - it is too bright?
    Herschel 2682:
    Favourite "double" of the night - a lovely symmetrical slightly squashed triangle - one white, one dimmer blue, one dim blue (looked red to me at first - WHY?)
    Apparently they are not gravitationally bound...
    On to Cassiopeia - I love this region of the sky - so rich in sights!
    M103:
    Initially sparse but very rewarding roughly triangular open cluster near Ruchbah - very nice at 50x magnification. I'm not normally a particular fan of open clusters but this is very pretty - The brighter half dozen odd stars are of visibly different colours and more dimmer ones pop out the longer you look.
    Stock 2 Open Cluster:
    This is a HUGE open cluster in Cas. I was packing the wrong telescope really - I could have done with the ST80 or even just binoculars. The views were almost better in the finder!  I need to compile a list of targets for the ST80 for one night...
    Pleiades:
    First view of the season as it cleared the trees. Another ST80 target really.  Last year I was sure I could spot nebulosity in between the stars - not this time but that may have been due to the moon...
    Packed up at 0030 as cloud started coming in....
    Closing notes:
    Swapping between the 24mm UFF and the Seben 24-8mm zoom really shows up the off axis sharpness of the UFF. I really need to replace the Seben (was great terrestrially though!) but with what? A zoom or fixed focal length eyepieces?
     
     
     
  6. cwis
    Started around 2200 - proper dark at last. It was warm - shorts and t-shirt. No wind - total calm. The seeing was weird - wobbles due to the heat, but clear and transparent. Stars were points, not fuzz, but wobbled about. Larger convection cells or something?
    Saturn:
    4mm (317x) Nirvana misted up in seconds - not impressed! May have been caught by dew - grass was wet.  Put it in my pocket to warm up.  Backed off the mag and tried the zoom at 8mm (159x) but the seeing wasn't great. A band visible on the planet (looked like a cummerbund position wise!), the Cassini division (Cd) was fleeting visible, more on the RHS of the planet for some reason?  Tried 24mm UFF with the barlow (106x) and got a very sharp image - wobbly but sharp. I like the view through this combination - very crisp wide sweet spot for minimal dob nudging.  Cd was visible but the whole planet was shimmering in the heat haze.
    Experimentation showed the best views were with 12mm zoom setting with barlow so 6mm (212x)  - a crisp but wobbly planet with the Cd very clear on occasion, and a band of darker tan/brown just below equator. 3 visible moons.
    Jupiter:
    Kept 6mm setting and moved to Jupiter. GRS clearly visible, bands all nice and clear - seeing very good. Jupiter was just clearing fence/lattice so expecting improvement when diffraction effects subside... Noticed "double star" effect of Ganymede and Europa being very close together in view. Tried the contrast booster filter at this point - made no difference really and colour cast annoyed more than last time so removed. Decided to search out some doubles and practice star hopping while I waited for Jupiter to rise to a more useful position.
    M2  Glob in Aquarius:
    Hopped from Enif which was just visible in the Rigel. 24mm (53x) Just a blob. 12mm - some granularity around the outside, 6mm, diffuse core surrounded by resolved stars. Seemed to move quickly at this mag - conscious of constant nudging. M2 is enjoyable to observe - a real impression of 3d depth and the longer you look, the more you see!
    2316 - bye bye Saturn - vanished over neighbours roof.
    2320 Jupiter:
    Seeing now good! Observing what I think are two barges on surface - one nearer the middle red/brown the other closer to the edge brown/red (dob view). Are these barges? Never had such a clear view of Jupiter so all these features are new!

    4mm now warmed in pocket was OK but views best at 200x odd with barlowed zoom set to 12mm.
    More star hopping - aiming for Dumbbell Nebula but got lost. Reoriented on Delta Sagittae after some moderate faffing. Nice wobbly but clear Airy yellow disk - seeing therefore pretty good!  Gave up on Dumbbell, thought I'd visit some old faves so pointed at Vega and on to the..
    Double Double:
    Clearly split both pairs at 8mm (159x). Just split (an honest no really, I can see a black line split) at 18mm (70x). 
    Sheliak (Beta Lyrae):
    White with very blue quite dim compainion. Striking contrast!
    Ring Nebula. I'm sure that the centre looks blue at lower magnifications. Is that possible from a Bortle 5 sky or  is my brain filling in or the red observation light affecting my colour perception? it looked more "filled in circle" and less "ring".
    Packed in at 0010 - small child ill so need rest. Check out the light pollution from London..

     
    0400:
    Awake comforting child - she has now dropped off. Nice! Saw Orion through window so snuck out with binos for a quick peek - first of the year.  All seems to be present and correct - Betelgeuse seems brighter again? Rigel still a double. M42 et al still there. Good! 
     
     
  7. cwis
    Day 3 of minimal sleep due to child with cough. Hey ho...
    Set up and cooled for 2215 and had a quick peek at Jupiter and Saturn. Very mushy at the 6mm (200 odd) setting that did so well the night before. Decided to come back later and see if it had improved.
    Hopped from Enif to M2 and this confirmed that the seeing was far worse than last night - couldn't really resolve any stars. Let's do a couple of doubles!
    Struve 2848 in Pegasus:
    Wide separation, split at 53x. Yellow/blue starts of similar brightness. 
    Tried to hop to Struve 2786 but overhanging branches were obscuring too many key navigation points, plus sky glow from London was obscuring key constellations to the naked eye. Frustrating!
    Moved to Altair (I could see this one as not over London!) to use as a starting point. It was a ball of angry fuzz at higher mags - no airy disk. 
    H N 84:
    Orange/yellow primary with dimmer and very blue companion. very pretty! Wide split.
    Decided to stay in this area of sky therefore observed the Coathanger nebula - it was obvious in the finder but underwhelming at 53x - it didn't fit in the view.  Like the Pleiades, another open cluster best suited to the ST80. I need to make a list of those and have a session with it at some point.
    Got lost on the way to Anser (Alpha Vulpeculae) and then spotted Albireo in the finder so stopped there for a while...
    M56:
    Small glob. Could just resolve some stars on the edges. The sky seemed quite bright or milky and the glob quite dim so upping the magnification didn't seem to increase the contrast as much as usual  - the glob and the sky both dimmed!
    Dumbbell Nebula:
    Finally found it - was looking last night. Much bigger than expected but quite faint against the milky sky. Swapped out zoom for the UFF to see if I got more contrast. Not really but it did look perceptibly blue at lower magnifications. Maybe my imagination, don't know.  It looked more "coke can" than "dumbbell" - like a rectangle in a faint circle as per poor sketch:

    M71: "Coarse" globular cluster. Quite big with readily resolvable stars. Took magnification well - far better than M56.
    Last look at Jupiter - still really fuzzy so packed up at 12:07.
     
  8. cwis
    First session for 12 days. A short one because I could see clouds slowly approaching and the moon would be up shortly (but not visible from my garden).
    Set the telescope up far earlier than last time and allowed it to cool with the covers on. As it was still nice and light I attached the latest version of the encoder mount and zip tied the processor and power supply to it. I set up at the south south west end of the garden with the intention of looking at some doubles near and in Cassiopeia and giving the encoders their first real test and trying out my new book:

    The book finder views are aligned to astronomical North which for some reason I am having difficulty getting my head around.  How else would they be oriented? Why am I finding it disorienting? 
    Eta Cas:
    Easily found just using the Rigel.
    White primary - Orange (to me) secondary at 5 o'clock (dob view).  Wide separation - obvious at 24mm (53X).  Seeing not great - more magnification didn't really make things any clearer. Had a quick look at Jupiter (just visible) and that was a blurry mess - should I have given the scope more time to cool or was it seeing?
    Sigma Cas:
    First PushTo. Need to read the instructions again but couldn't align to Eta Cas after picking up a pointing error. But just moved scope to the same offset away from Sigma Cas and it was the brightest star in the 53x view. Cool but not ideal...
    Tighter double - no split at 53x. In fact it was difficult to see it was a double at that mag with positioning errors over the eyepiece and coma if away from the centre of view masking the bulge in the primary. Split was clear by 18mm (70x). Stars similar white blue colour - primary maybe bluer?
    Messed around with pushto and encoders for a while at this point testing. Feels like I'm wasting good observing time but I need to do it if I want to complete them.
    Polaris: (In focus for once!)
    Seeing seemed to have improved as was spotting signs of airy disk in the primary at higher mags and  the secondary a lovely sharp pinprick of light. Obvious even at 50x.
     Collimation looked loads better than last time (maybe more contrast?) but totally forgot to test in situ with the Cheshire.
    Moon was up now and washing out the sky but was not visible from my location. I could also see clouds approaching...
    M81:
    Aligned again on Polaris and Caph and tried a pushto to M81. Was in view at 8mm (160x) Wow! Hope that's repeatable...  No real shape was visible (unlike in the past with this scope) due to the moon and probably Jupiter washing it out. It looked like a mini Andromeda. The sky was basically blue at this point!
    Kochab:
    Final Pushto to Kochab.  Lovely Yellow bright star - no visible Airy disk but nice symmetrical twinkle.
    Notes:
    Dob action feels sticky. Not really noticed before but now I'm trying to do sub degree pushto moves it's more of a pain. Both Axis - seek advice!
    Need to mask light from micro controller and power source.
    Need to work out how to take decent notes - have a method and stick to it.
    Book is excellent - need to work out finder views if I'm going to use it as a star hopping guide which looks like it would be part of the fun. Would be a bit of a waste just to use it as a list of interesting targets and use PushTo.  I'm really loath to mark it with pencil too - it's too pretty!
    Moon and Clouds push me indoors:

  9. cwis
    I saw the CO was showing green for a few hours around 2300 - so took the dob and the st80 on the Azgti outside around then. I first tried the lightweight travel tripod with the st80 but the altitude clutch couldn't hold the weight - either need a new head or print a counterweight holder.
    Set up the st80 on the Azgti while the dob cooled. Still running it off the broken AGM battery I took off a bike - nice boat anchor for additional tripod stability! Must print a holder for it to hang underneath the tray. Pointed it at Andromeda and promptly forgot about it. Came back later to nick the contrast booster filter in the diagonal....  While I was setting up a meteor flew over my head away from me - quite bright.  Came from the South West - not sure what that would be from.
    Once the dob had mostly cooled I pointed it at Jupiter. Last time I had the best views (to my eyes) with the 25mm plus barlow giving 100x. Wanted to try and push it further this time so tried the 24-8 zoom at the 10mm to 8mm end.  I think this is when I nicked the contrast booster - not sure whether it helps but certainly doesn't spoil anything, once you get used to the colour cast.
    I think the seeing steadily improved - could clearly see the GRS to the RHS (dob view) and banding etc. Then I noticed Ganymede  looked a bit coma-ey and the sharp spot looked to be a bit to the left of the centre of view.  Very narrow sharp area with the cheapy zoom - Seriously thinking about a Baader but no-one has the matching barlow in stock....
    Down the rabbit hole of star-collimation for the first time. I don't think I've ever looked at Polaris whilst any 'scope has been in focus but this is the first time I've attempted to shift the primary "on the fly". I thought I improved it and swung back to the Ecliptic to see Saturn vanish behind the neighbors house. Wups. Back to Jupiter.
    The GRS was nearly central now and a shadow (looked it up)  Io. Couldn't make out Io itself though. Ganymede looking better too, but still not quite right.  Resolved to have a look at collimation with a Cheshire ASAP but not then - having too much fun. Watched Io traverse for a while (or its shadow anyway). Clouds started to gather in the West (thin high ones)...
    Noticed that according to SkySafari  (SS) Neptune would be mag 7ish to the East and so decided to try and star hop to it. Turned off mag 7.1 and dimmer stars before I could see views in the finder similar to that shown by SS.
    Found Bluish star? Not certain. Must complete PushTo system.
    Clouds started pushing in to the West and the North and I think seeing started to go a bit - might have been my tired eyeballs.  One last look at Jupiter (Io moves quickly doesn't it!) and started bringing kit in at about 0145.
    Cheshire View:
    Looks like secondary moved at some point in the last few months and the star test made me move the primary to compensate. Secondary screws were quite loose.  Had the usual "Turning the tilt screws causes the secondary carrier to rotate" fun but got near enough in the end. Nipped screws up tighter. Slipped collimating cap on to check I could see all primary clips - yup - lovely!  Back to Cheshire for primary - a few tweaks and bang on.
    Mental note - make sure Cheshire is seated in eyepiece holder before tightening thumbscrews. Think I'll check collimation when in-situ with a red light next time while the scope cools...
    Fun night!
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