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Astro Adj

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  1. Thanks Ron. Actually I didn't need to hold the camera to the EP, I'm sure I'd never a picture of anything if that was the case! I've got an adapter that lets me attach the camera to the EP, and also a shutter release cable so that I don't send the image wobbling everywhere when I push the button! I think my scope is now collimated correctly, although won't know for certain until I can get back out there. I can't wait to try again when the scope is performing at its best! One thing that surprised me was how quickly the moon sped through my FOV, even with tracking on. I wondered if this was due to the speed of the moon being very different to the sidereal rate that the stars follow?
  2. I recently messed my scope's collimation up quite badly whilst trying to fix something that wasn't actually wrong! Rather than drive to my normal dark site I decided to take the dob out into the garden to see if the remedial adjustments I'd made had done the trick. The bad news is my collimation was horrible. I couldn't bring a star into focus, and mistook the double star Algieba for Saturn! The good news is that the moon, whilst not pin-sharp, seemed acceptable. I decided to attach my little 4MP digital camera to the EP via an adapter and take some images! The picture below is the best I could do, I found it hard to focus the image as the camera's screen is tiny and very low resolution. Nevertheless I was happy that it turned out okay. I'd definitely welcome any advice or tips as I am entirely new to this but would like to improve as I really enjoyed taking the images! Camera was a Nikon Coolpix 4300 in B&W mode. EP used was a 25mm plossl with a SW LPR filter attached. I used Picasa to tweak the picture (added a tiny bit of sharpness and increased the shadows very slightly) and correct the orientation. Right, I'm off to use my new colli cap to sort this scope out!
  3. Well, this is embarrassing. I decided to have a play with the scope last night under some decent lighting. Before I did anything I thought I would take a picture of the offending black line that was blocking part of the primary. I peered through the focuser, and reached up the side of the tube so that I could rest my finger on the lip of the OTA, directly above where the mysterious black line was. I then looked down the tube at the spot my finger was pointing to and proceeded to kick myself. Hard. Anyone like to guess what I saw? My shroud had become loose at the bottom and part of it had snuck in the gap between the top and bottom sections of the tube. As a result, when the scope was extended part of the shroud was left inside the tube, and obviously that part completely obscured the section of the primary it was above. Doh! I didn't have time to make any adjustments after that as something came up, but needless to say I felt like a bit of a wally. Then again, I learnt several new things about the art of collimation which will no doubt be of great use. I am actually looking forward to getting the HoTech out now! Oh, and while I was drilling the hole for my collimation cap I thought I'd also drill a small hole through my screwdriver's handle. I threaded a piece of lace through the hole and now I can keep it wrapped around my wrist when adjusting the secondary - no more nightmares about dropping the screwdriver onto the primary!
  4. I agree with Mick, and faced a similar buying decision recently! The only other consideration is whether the scope's size/weight is something you need to pay attention to? I couldn't fit the 300P into my room (well, technically I could, but it would have ended up going out of the window shortly after my wife saw it...) but ended up going for the Flextube version as it didn't dominate the bedroom when collapsed. If you can live with the bigger size, the 300P will reward you with what you can observe with it that wouldn't be possible in 250. In fact it can gather 44% more light than the 250!
  5. Mick, I think Mars was disappointing because of the poor conditions. I'm not sure how to describe it, but whereas the site I was at usually has a limiting magnitude of around 5.5 on this occasion I struggled to see the 3 stars that make up Orion's belt! At this point there were no clouds in the sky, I can only assume it was mist or something similar. Mars actually gave some detail (a dark scar slightly northwest of its equator) but I couldn't bring it into any sort of focus. As a rule of thumb, though, how long should I allow for the scope to cool? I usually leave between 30 and 40 minutes depending on the difference between the car and ambient temperature. I have also taken to driving to the site with all the windows open! Mark, yes, that does make sense. I've not tried to see if the laser is centered on the secondary (both immediately after it leaves the HoTech and on its return journey) but would I do this by using a small mirror to look at the underside of the primary? If so, at which point would I pop this step into my routine? Would I check and adjust (if necessary) at the same time I perform the check advised by Mick? (Rotate the secondary until all 3 primary mirror clips are visible and the secondary is a circle in the centre of the image through the colli cap). Thanks for the tip!
  6. Thanks Mick. Actually that's almost exactly what happened - I took the scope out but after about 10 minutes the sky clouded over. I wasn't happy with the views I had of Mars during those 10 minutes so decided to investigate, which prompted a lot of messing around after I realised only one primary clip was visible. Thing is I wasn't really sure what to change so tried all sorts, my thinking being that if I turned a screw the wrong way I could always turn it back again! I think I'll have another go at home tonight with the colli cap. If it seems okay I'll deliberately mess the alignment up then start again, and repeat until I've got the hang of it. Ironically I thought I already had it sussed, and was so pleased with the HoTech because it made the process quick and painless. Just goes to show clever tech is useless unless the operator knows what information is going in and what should be coming out! What benefit would a cheshire collimator bring to the party? Does it perform the same job as the colli cap but with greater accuracy or is it used for a different stage of the collimation process? One other question, do you unlock the primary locking screws before adjusting that, then tighten them once you've finished? I've never actually used them!
  7. Thank you both for the suggestions. I do not have a collimation cap, so that will be my first port of call. I love the idea of using the blank - I actually have 2 (one for the 1.25" adapter and one for the 2" adapter) so I'll use one of them as a colli cap and the other as my dust cap. Once this is on the focuser, and I've loosened the centre screw and the 3 adjustment screws, is it then a matter of looking through the hole in the colli cap and rotating the secondary until all three clips are visible? From this point should I commence my routine or is there anything else I need to be aware of? I understood from reading some articles on collimation that before I adjust the 3 screws on the secondary I should first ensure the secondary is in the right place by loosening the centre screw and moving it up and down the tube. Is this necessary or is rotating the secondary enough? Mick, do you tend to collimate every session? I am doing this currently but have read that actually the secondary should hold its alignment reasonably well for some time. I just wondered if I am fiddling with it unnecessarily. Thanks again for the help!
  8. I've recently bought HoTech's SCA laser collimator after reading lots of very positive reviews. It seemed like a good match to my 12" dob as it meant that, in theory, I should be able to collimate it accurately and quickly all by myself. Unfortunately I think something is going awry. After I have finished my collimation routine the laser is in the middle of the donut on the primary, and the reflected laser is exactly in the middle of the grid on the side of the HoTech. Just to go over the steps quickly (in case I've missed something), here is my routine: 1/ Insert 2" adapter into focuser, insert HoTech into this. 2/ Tighten HoTech until I am unable to rotate the compression ring any longer (I assume this means the SCA has done its thing and centered the laser in my focuser) 3/ Switch laser on and look at the donut on the primary to see how far out the laser is 4/ Adjust the 3 allen key bolts until the laser is dead centre on the donut (note: I have noticed that the 3 bolts are all relatively loose to achieve this) 5/ Go to the end of the scope, and look at the laser grid on the side of the HoTech. 6/ Adjust the primary mirror (using the 3 knobs) until the reflected dot is bang in the middle of the targeting grid. In fact the dot 'disappears' in the middle of the grid - I can only see the crosshair surrounding it. 7/ Return to the secondary mirror and make any adjustments to re-centre the laser in the donut if necessary. 8/ Turn the HoTech off and remove the device. However, when I do star tests and pull the star out of focus instead of seeing concentric circles I end up with a flat edge across the image. If you look at the letter 'C' and draw a line between the two 'ends' it will look similar to what I'm trying to describe. I then decided to peer down the focuser, expecting to be able to see the 3 primary mirror clips. However, I could only see one, and directly opposite the clip I could see was the same black line cutting off the rest of the circle. I've edited a picture from Astro Baby's excellent article on collimation (I hope she doesn't mind - really should have asked first) and attached it below. I'm pretty sure this is not right. My thoughts are I've either done something wrong, the HoTech is not completely accurate or I have a more serious problem with the mirror itself. After spending a lot of time researching collimation I have noticed there are a few things I do NOT do, namely: 1/ Use the central screw on the secondary to move it up and down 2/ Use the locking screws on the primary 3/ Use a system of 'loosen one, tighten the opposite' when adjusting the secondary - I tend to move to each one in turn and try turning it CW, then CCW and see which direction moves the laser closer to the centre of the donut. I get each one as close as I can then move onto the next screw. Could one/all of the above be the problem? If not, can anyone help me find a solution? Thanks everyone.
  9. Do you know which RDF you have? My old Skywatcher scope came with one and I could help you adjust that...I wouldn't be sure about other models though! On mine there are 3 small knobs that can be turned. One is an on/off control (also allows you to increase/decrease the intensity of the red dot), and the other 2 are the adjustment knobs. One is for vertical adjustment, the other horizontal. If it helps, on mine one of the knobs is underneath the back of the RDF's body, the other is on the right-hand side, near the end of the RDF. Once you've found the adjustment controls, it's just a matter of fine-tuning the alignment. I start with an object like a chimney or tree that is a good distance away, and make sure that when the object (or, more likely, a specific part of that object) is centered in my eyepiece the red dot is placed on the exact same part of the object. After the daytime alignment I repeat the process on a star - the daytime alignment should be sufficient to get the star in your eyepiece's FOV, and from there you can make the tiny adjustments required to get the RDF directly on it when the star is centered. I find decreasing the brightness helps me to see exactly when the red dot is on top of star. Hope this helps a little.
  10. Thanks for the link. It appears they have sold out, but I've bookmarked the site and will check back frequently. In the meantime I am going to go to work on the edge of the secondary with a Sharpie!
  11. Thanks for all the replies, everyone. I've had a think about it and am going to invest in a QuikFinder. Although it means I'll be going without the extra circle, the fact it is at an acceptable height without requiring a riser and is more resistant to the nasty machinations of the dew monster sealed the deal. Eventually I would like to have it beside a RA finder, just as Mike has. I think that, combined with a Wixey and a azimuth circle should really make a difference to my observing sessions. Thanks again for the help, I expect I'll receive the QuikFinder and Wixey within the next couple of days (FLO's delivery speed is amazing) so I'll be sure to include my experiences as soon as I get some clear skies.
  12. Thanks for the advice. I hadn't thought about the profile of the finder, but now that you mention it one of the problems with my current finder is that it is quite close to the OTA which can make it awkward to look through. As such I guess the Quikfinder would be better in this respect. I understand the idea of the Telrad is that you can use the degree circles to hop accurately to an object, so if an object was 10 degrees away from a specific star or other object you could make two 4 degree jumps followed by a 2 degree jump. But does that work in practice? I was thinking I would be more likely to just centre the object I was planning to observe in the 1/2 degree circle then use the telescope with a low-power EP from there. In this case, though, would I be better with a simple RDF?
  13. Mick to the rescue again! I have added this to the list of 'things I need to do to my dob'! Thanks for the link.
  14. I am in desperate need of a zero magnification finder for my dob, and both the Telrad and Quikfinder seem like superb bits of kit. I was just wondering if anyone has an opinion as to which is better? As far as I can tell, the Telrad has an extra circle (4 degrees) but is heavier. Are there any other differences? Would both finders slot into the baseplate that is currently occupied by my (mostly useless) straight through finder? Or would I need to do any drilling etc to mount either one? They both seem to be around the same price (£35-£40) so I'm currently leaning towards the Telrad. But I would greatly appreciate some thoughts from anyone who has owned one or the other (or, perhaps, both!). Thanks everyone.
  15. Chris, is there a particularly set of filters you would recommend? The price for a set seems to vary enormously! Stuart, excellent work! That gives me some hope, I'll have a go at clicking (agree that sounds more agreeable than stabbing!) next time the clouds part for any period of time. Twotter, that EP looks identical to a Meade 32mm EP that I use currently. It also has the same AFOV - 52 degrees - which in my scope gives a TFOV of around 1.11 degrees. In my old scope it produced a TFOV of around 2.56 degrees, which was much better for viewing M31. The problem I have is if I go much more than 32mm I start to have an exit pupil figure of more than 7mm, which isn't recommended. The only solution I can see is to invest in an EP with a bigger AFOV (you can get up to 100 degrees now!). Andrew, thanks for the link. I read that thread and am definitely going to copy your modifications. Could I ask where you obtained the flocking paper from? I've found some suppliers based in the US but none here unfortunately. Would you be able to point me in the right direction?
  16. I really enjoyed that report, feel that I've picked up some very useful information and learning more about the objects I observe makes them even more special! One question, you mentioned using a combination of a wixey and an azimuth circle to determine when you were in the correct area, but what exactly is an azimuth circle? I have a wixey on order but figured I would need to move the scope in azimuth until I spotted my target. If there as a similar device that works in azimuth that would be brilliant!
  17. Congratulations on your purchase! I have this scope too and I love it. I was able to see some fantastic objects using it and think it's an absolute bargain considering it's performance. Looking forward to your observation reports!
  18. Twotter, I can definitely see the appeal of wider FOV EPs! I may well invest in an ultra-wide EP, but first need to discover what focal length I will get the most use out of. Shane, it would be good to hear how you got on - do get a report posted if you can find the time. It's the best feeling to find something unassisted, isn't it? It was one of the main reasons I decided against a scope with GOTO capability. I also stumbled across the link to the TriAtlas charts through your post - so thanks for that! I had a look for the Cassini division but couldn't make it out. I hoped this was because the rings were almost completely edge on, but perhaps the combination of my inexperience and contrast issues conspired against me. Did okay on moons though - I counted 5 at the EP, but a session on Stellarium the next day revealed that one of my moons might well have been a star. But I'm certain I spotted Rhea, Enceladus, Dione and Titan. Andrew, thank you for the very informative post. Interesting to hear you have experienced similar problems to me, and it adds some assurance that it's not just my scope that has an issue - I'd hate to think my mirrors are at fault but it's a difficult thing to test, especially as I don't yet know what the scope should be capable of. I did a little research on the subject of curved-vane secondary supports, and found an interesting image which I've posted below. Although I do get the classic 4 spikes when viewing bright stars, the effect that blighted my viewing of Saturn was very similar to the picture showing how the diffraction looks with a curved support - a roughly circular haze engulfing the planet! Very strange. On collimation, although I'm happy the scope is collimated as accurately as it can be (cross-hair is bang in the middle of the doughnut, laser reflected by the primary is dead-centre on the grid on the collimator) I understand it could still be out of alignment if there is even the slightest discrepancy with the collimator itself. How do you typically test your collimation? I tried intra- and extra-focus on Sirius, but the concentric rings were moving too much for me to see if they were spaced correctly. Are there any other techniques I can use as a test? I'd be very interested in seeing if you experience any success with your DIY projects to eliminate stray light. I am THE most cack-handed buffoon when it comes to things like this, and would almost certainly do more harm than good if I tried to do something like this. However, if you get on well with it I might have to give it a go! Chris, I think I might have caught filter fever now. I've not had the chance to use my LPR filter yet, but I was really pleased with the OIII. Next on the list is a set of coloured filters for planetary viewing, I just need to learn more about them in order to decide exactly which set to buy. Ken, would you be kind enough to expand on your post regarding rotating the secondary? I was just wondering if my mirror needs attention, but I'm not 100% what it should look like in relation to the primary.
  19. Stuart, that issue sounds similar to the one I experienced. Do you also find that sometimes you need to hold the button down for a certain period of time (maybe a second or 2) before the scope responds? That is the main problem I have, as the movement takes me by surprise and I end up over-shooting my target by some margin! I am going to try 'stabbing' the buttons rather than holding them now - I am hoping I can learn how many stabs it takes to get the scope moving, and therefore be more accurate when it comes to stopping the movement. If that doesn't work I'll just keep practicing in order to learn when the scope will begin moving. Mick, thanks so much for the link you provided. That list is an incredibly useful aid, and I've already printed it out and popped it into the folder I keep all my maps/sketches etc in. I think it will rapidly become my number 1 tool when I'm out and away from the wonders of Stellarium! I've given some thought to balancing my scope. With my 130 it is simply a process of adjusting the counterweight, but I imagine balancing a dob requires a little DIY? I was thinking of attaching some circular weights to the end of the OTA, but then realised I'd need a method of actually testing how much weight I required and a way to adjust the load depending on what EP / camera set-up I was using. Not to mention a way to actually get the weights themselves on the scope without them tumbling off each time it is moved! Any ideas? Also, I think I'm right in saying that this will only balance the scope in Altitude - how should I go about Azimuth balancing? Steph, you are probably bang on the money there! My first scope had slow motion cables, so in a way I have been spoiled when it comes to fine adjustment! Having said that I am looking forward to becoming more proficient with the new scope - it will just make any successes I have even more satisfying as I'm having to earn them! Julian, very interesting to hear you experienced the same problem when observing. I also didn't see this effect when looking at Jupiter, but attributed this to the scope as opposed to conditions. But now I think about it, I was able to pop out in little more than a t-shirt when Jupiter was visible, whereas observing now requires Eskimo impersonation. Do you think the EPs also need time to cool down in order to work optimally? I've attached a couple of pics below, I realise everyone has probably seen this scope before, but thought it might be useful to show a size comparison between the 130 and the 300. I am pleased with how compact it is when collapsed - when you take into account the space needed for the tripod and mount, the 300 doesn't really take up more floor space than the 130 with all its bits!
  20. Thanks for the comments everyone. I love this forum as I learn so much in such every time I log on! Ian, I've heard of ghosting, but need to look into it further. Am I right that it's caused by light moving through the inside the of the EP being dispersed? I will try again to see if it is the magnification that was causing the problem (regardless of EP) or whether it only occurs with specific EPs. That might help isolate the issue! Seb, I'm hoping the 300P will indeed open up so new objects. Ideally I'd like to work my way through the Messier list for a start. I like the idea of having set objects to locate, and the Messiers seem as good a place to start as any! John, are you able to go up to 340x regularly? I understand that ordinarily 300x is about the most we can use in the UK? I was rather hoping this was not the case! I will definitely try for M13 again soon. I think your Ethos (very jealous, btw) should give a TFOV of around 1.08 degrees, and with a 32mm EP I believe my TFOV is around 1.11 degrees. So it sounds like that would be a good place to start! Is there an accepted 'best' magnification for M31? I have been thinking about getting another EP to give a wider FOV, however I think I'm right in saying that if I push the focal length of the EP past 35mm I'll end up with an exit pupil in excess of 7mm. What sort of effect would this have on the image? Steve, thanks for the tip! If it is indeed condensation, are there any paricular ways to let the EPs rid themselves of it? Steve - good suggestion! I actually found a lumberjack jacket in Asda for £8 2 weeks ago, and it was lovely and warm. I usually wear walking boots with 2 pairs of socks, but stupidly forgot to wear them!
  21. Date: 4th March 2010 Time: 2100 ~ 2300 Site: Dark Site nr Assington Weather: Clear Limiting Magnitude: 5.5 Seeing: 5/10 Transparency: 7/10 Guidance: None Site Notes: My first proper observing session with my new scope deserved a spot somewhat more conducive to DSO hunting than my back yard, and so I went for a drive and ended up at a spot just north of Colchester. There was a single tree to the northwest, but aside from that I had viewing that was completely unobstructed. Observation Summary: Today’s session had both highs and lows. Starting with the former, I had some splendid views of M42. I was also able to spend time looking at Mars, Saturn, M44 and M45. I’ve recently invested in an OIII filter as well as some new EPs, and pleasingly they all performed admirably. Unfortunately, I was rather disappointed with my views of M31, and had a number of teething problems with my new scope. Comments / Report: First of all, this report is…enormous! I don’t know how it happened, only that I started typing and ended up with pages and pages before I knew it! Sorry in advance for such a massive post, but after writing it all I couldn’t decide which bits to chop out so figured I’d just include everything. Please forgive the terribly unscientific presentation! Due to various reasons I’d not been able to get out to observe properly (i.e. at a site that had acceptable levels of LP!) for some time. However my new scope arrived last week and so I was desperate to get out there and see what it was made of. The scope is a Skywatcher Skyliner 300P Flextube Auto – the name is almost as long as the scope! Anyway, my reasons for buying it were that I wanted to spend more time DSO hunting, whilst still having a scope that could provide good views of the planets. After reading some reviews I decided this was the scope for me. I am going to write a mini-review of sorts, so I won’t go on at length about the scopes merits here! I set up at about 2030, and began observing at around 2100. Once again I managed to leave my star map at home, so had no material to use as a guide. However, sadistic as this sounds, I actually quite enjoy hunting for my prey so I didn’t let this worry me! I used a HoTech laser collimator to collimate the scope, and performed the alignment routine as advised by the manual (basically, point the scope North, turn it off then back on again – slightly easier than the procedure for the 130PM on its equatorial mount!). I immediately tried for M31, as I’ve been itching to get a proper look at this galaxy for ages. Unfortunately, even though I aligned the finderscope before heading out, it was way out of sync with my scope. I decided to use Mars as my target for alignment purposes, and after about 15 minutes had the finderscope crosshairs and my EP FOV aligned. I decided to study Mars as I was already pointing to it. Unfortunately I was unable to discern any detail, and found that there was a wash of light over and around the planet which impeded my viewing. It looked as though Mars was emitting light of its own as it extended from the planet out to about 4 or 5 times its diameter. I’d not seen this in my old scope, and the same effect was present when I viewed Saturn later too. At this point I decided to try for M31 again. At this point I’d like to quickly say I am going to swap my finderscope for an RDF or similar zero power device ASAP. Finding targets is so much more difficult without the RDF! I moved the scope in azimuth first, aligning the centre of M31 with the centre of the OTA. I then used the hand controller to slew slowly up and down until the fuzzy revealed itself. This took about 10 minutes, due in part to the problems I encountered with the auto system. Whilst trying to make fine adjustments the motors frequently failed to respond to my inputs, and this caused me to ‘over-shoot’ my target my some margin when they did eventually respond! I’m not sure if this is due to the clutch not engaging properly or if there is just a certain amount of slack in the system, but it did make centering objects more difficult than it should have been. Eventually I had M31 in the centre of my 32mm plossl. This gave 47x magnification, and I could make out the bright central core but little else. I then changed EPs to give varying degrees of magnification from 150x to 300x. Unfortunately I was unable to see any further detail than the original 32mm EP had displayed. I was rather hoping to see dust lanes, and the shape of the galaxy. At this point M31 was at an altitude of around 18 degrees. I wondered (out loud, as I recall!) if this was too low for the detail I was seeking to be revealed. I also questioned the collimation of my scope (as I was completely reliant on the HoTech working accurately) and even the optics of the 300 itself. Feeling slightly disheartened at the view my scope provided of its first DSO, I decided to move on to a new target. There was only one option – M42. This looked stunning in my 5” 130PM, so with an additional 7” of light-gathering power (equivalent, I believe to around 5.5 times that of my other scope) I hoped this would be better. And it was. Again I started at 47x magnification, and could immediately notice more detail than I’d ever seen before. I decided that M42 would be the perfect object to test my new SW OIII filter on, and set about popping it into the 32mm. Back at the EP, and I could definitely see the difference. The outer edge of the large, curved part of the nebula was more apparent and the nebula itself stood out much more than the stars it contained. In fact, this effect was so apparent I now refer to M42 as The Angry Shrimp. You know, those little devils that have antennae specially adapted for boxing? Well that’s what it looked like – the stars themselves were leant a blue/green tint by the filter, further adding to The Angry Shrimp’s menacing appearance. The core of the nebula looked like the shrimp’s shell, and the curved could resembled his antennae, one sprouting in one direction and one in the other! I was so scared of his fearsome visage I decided to switch EPs in order to zoom in and change the view! Again I used every EP in my arsenal, and also combined a couple with my new Ultima 2x barlow. I was extremely impressed – whereas my old SW one clearly affected the image this Celestron model seemed to not impact the view whatsoever. I even popped my 5mm Hyperion into it (for 600x magnification) in order to study the trapezium further but was thwarted by my inability to a) focus the image and keep up with the rotation of the Earth! After that, I decided I would scan a few old favourites, hopeful that they would be as enjoyable. I had a look at The Pleiades and the Double Cluster in Perseus. Both were splendid. I then decided to have a look for M44, as I’d not seen it before. I could clearly see the 3 stars that form a triangle around it, and could make out a fuzzy patch by using averted vision. Thus began the process of manually moving the dob in azimuth before going to work with the hand controller. Again it took some time, but I was able to home in on M44. I enjoyed the view through my 32mm EP most, as at a TFOV of c. 1.11 degrees I could fit the majority of M44 into my FOV. Next on my hit-list was Saturn. It looked splendid through my 10mm SW plossl, and I decided to combine my William Optics 20mm with the Ultima to see how the image changed. I felt the contrast was improved slightly, and where in the 10mm the body of the planet and the section of the rings that passed over it looked uniform, in the 20mm combo I could differentiate between ring and planet. I tried to push the magnification to 300x but met with little success. The peculiar light that impaired my viewing of Mars also made an unwelcome return, again extending 4-5 times the diameter of Saturn. By this point I had lost all sensation in my toes. The prospect of a nice cuppa and a crumpet or two was commanding my legs to jump into the car and return home with all haste. However, I had one final target I wanted to observe. This, like M31, was one of the reasons I bought my new scope. I hoped it was visible, and began scanning the sky for Hercules. This took much longer than I’d hoped! The last time I looked at him, Hercules’ body was almost perpendicular to the horizon. This time I think he’d had slightly too much vino as he was at a very curious angle! As a result I was looking between the wrong stars for my target - M13. To add insult to injury when I did find the correct 2 stars I realized that a tree (in fact, the only tree anyway near me!) was completely blocking the view. I spent a few minutes wondering if I could move the scope, but as it would need to be literally in the middle of the road I decided against it. I asked the offending tree to move over several times but it was intractable. I took the fact I was talking to a tree as a sign that it was time to pack up, and decided to leave M13 for another night. Overall I found the session to be a good learning experience. I have enormous respect for those brave souls who use a dobsonian without any kind of automated support. How they manage to nudge their scopes along when tracking targets is beyond me! I didn’t get the results I was hoping for, but I think that the seeing may have contributed to this. When performing a star test early in the night I the concentric circles surrounding the star at both intra- and extra-focus were jumping wildly, which I think indicates pretty average seeing. Unless this was caused by poor collimation? I’ve still got so much to learn! I’m looking forward to my next session, hopefully it will be under more steady skies. I am also going to spend some time with the scope in order to get accustomed to the tracking (currently, even in tracking mode, I have to hold down a directional button in order to keep the object centered – a trick which isn’t particularly effective when I am at high magnifications) and the slack I encounter when trying to make small adjustments. I’d also be extremely interested in hearing from anyone who can help me with any of the problems I encountered – I am sure at least half of the issues are down to errors on my part! Thanks for reading, and apologies again for the wall of text.
  22. Likewise, I was able to discern some detail at Saturn's equator. Looked like bands of colour (oranges and yellows) but I was unable to observe it properly due to some teething issues with my new scope. The moon was incredible, if a tad bright - I came away from the eyepiece wincing after about 30 secs of studying the surface detail. That was my dark adaption gone for a good 20 minutes too! COuldn't get a good look at Mars as it had a strange orange glow surrounding it that washed out all detail. Not encountered this effect before, it looked like the halo the moon exhibits except it was 'filled in', from the centre of the planet all the way out to about 5-6 times Mars' diameter. Unfortunately I was unable to see M42 or M13 as I'd hoped due to houses blocking the view throughout my observing session. Something for next time!
  23. I can definitely see the appeal of both. Looking through the finder was really quite awkward, the OTA almost seemed to be in the way at times! I need to invest in a decent battery and charger first, as I don't think the batteries I'm currently using will last for very long. Once that purchase has been made a Rigel / Telrad and RA finder are next on the list!
  24. Well...the first light report is going to have to wait until I've been out tonight I think! I did manage to get 2 hours under clear skies yesterday, unfortunately a comedy of errors prevented me from using the scope fully. Part of the problem was unavoidable (bad light pollution and tall buildings on all sides of me that prevented viewing many objects) but a big part was down to me being a plank. I cooled, collimated and aligned the scope with no problems, but totally forgot to align the finderscope! My RDF from the 130PM was also no good, so I was left with 12" of light-gathering power but no means of accurately directing the scope! I did however experiment with the hand controller, and again had mixed results. I'll save the details for a proper report but suffice to say it doesn't always behave as you'd like it to! Not all doom and gloom though - I did manage to view the Moon and Saturn, both of which were stunning. The biggest victory I had last night was regarding moving the 300 around. It is much easier than I imagined. My room is on the 3rd floor, and getting the OTA downstairs was no problem at all. I'd estimate it weighs somewhere in the region of 15kg, and when collapsed is not too bulky to be awkward. The base was more tricky, being wider, but still not a problem. Very pleased I moved it alone, as it means I'm not at the mercy of someone else being around if I want to pack the kit up and go. Bonus! I am going to align the finderscope and the RDF today, and hopefully get out for Round 2 this evening. The weather doesn't look as accommodating as it was yesterday, but hopefully I'll have long enough to really give the scope a workout.
  25. I've just popped out to look at the sky during a break at work and it looks like tonight might be the night the 300 gets its first taste of the night sky! I am touching wood as I type this, hopefully I've not just jinxed myself! Unfortunately I won't be able to travel to my usual dark site as I need to be close to home this evening. The limiting magnitude of my back yard is usually around 4.2, which hopefully will be adequate for a test run. I've already drawn up a shortlist of targets, getting very excited now!
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