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LouisJB

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Everything posted by LouisJB

  1. that's pretty good, with an ED80 and DSLR? That gives me some hope. How many subs and what length did you use to get that image?
  2. Thanks for the replies. Tim's image is amazing. I notice that was with a native 2800mm focal length 11" tube and a tiny CCD sensor, so giving a completely different image scale to what I can achieve with what I have (1000mm and relatively massive APS-C). So this probably isn't a natural target for my current setup. I might have another go sometime though, something did come out but I think there were guiding troubles and my ST80 did fog up a few times :s It's a good target to aspire to, but maybe it's a few levels above what I can achieve today. Lovely object though. Who knows, maybe I'll end up with a similar tube one day but I'll keep practicing for now.
  3. You can get the 130P on EQ2 for about £160 and add an RA motor afterwards. If you do the mod to allow prime focus you wouldn't have a terrible starting point. That's how I got started. The 130P actually makes for a really nice OTA. It's only since I got a coma corrector I might replace it with a 130PDS now since it needs a 2" focuser. Although I have the 200mm GSO there are times you want that wider field, so it's not like it's a terrible instrument, the 130P (particularly) the PDS is compared favourably to the ED80 which is like the de-facto starter scope for imaging. I just mention in case you might want to trade the M for the P now and add a motor after. It's just an idea, either way you'll have some limitations especially in that price range but you can get some reasonable shots with a 130P - in fact I used it for a bit when I upgraded to the HEQ5 pro (as my starter setup to learn the basics of imaging) and although not amazing compared to some peoples images I was able to get things like this with my normal APS-C DSLR... Anyway I doubt you'll be disappointed with either, just offering you some info so you can make the best choice for your circumstances. You'll probably find you need quite a lot of starter accessories so allow for that too.
  4. I tried to get some data for this Sunday night but now I come to stack and process it I realise it's a bit of a failure. Too bad even to post up. Is this a hard object to image - with my modest equipment, should I give up or maybe persevere? Perhaps this is the domain of the high focal length SCT or a tiny chip size is required. I was very small in my image, I guess not helped by my APS-C DSLR chip-size. I couldn't locate it at all with bins, not sure if that says something about my local sky at the time. Compared to say M66 which appeared after 3 3min subs on the same night (and was low in the sky) it seemed really to not be very easy as a target at all. Perhaps I had wrong expectations. Being so famous and with it being the 1st Messier I suppose I thought it would be relatively easy...
  5. well thanks, it's nothing compared to yours - did you compose the final image with colour? I'd be interested to see what you got
  6. The other night while I was out there my ST80 dewed up, mid-imaging, leading to loss of guiding. Had me puzzled for a bit, first time that has happened. The main OTA was ok. Was able to rescue by borrowing hair-dryer but naturally this wasn't ideal. So I might make a dew shield. What is the best foam material to make one from. Is this sort of black foam any good? http://www.ebay.co.uk/itm/BLACK-NEOPRENE-PLAIN-SPONGE-FOAM-RUBBER-SHEET-VARIOUS-SHEET-SIZES-THICKNESSES-/261338185781?pt=LH_DefaultDomain_3&var=560247776763&hash=item3cd8f84035 and what thickness is good? I'll probably make a little one for the ST80 and a bigger one for the 200mm tube, even though that has not had dew issues yet, I'm sure it will happen at some point. The other thing, I think my main 200mm tube could do with some internal flocking, maybe not the whole tube but the critical areas. Where in the UK can I get the right sort of material. I want sticky-back stuff? FLO seem out of stock. If you have any recommendations that would be good, as I don't want to use the wrong stuff. What about flock-board, how does that work? thanks in advance.
  7. thanks everyone. I know it's not great, but that anything showed up was a bit of a surprise, first time I've seen anything like that and that I've pointed to that part of the sky. I realised after that the tube wasn't colminated. I think I knocked one of the locking nuts, after noticing I pinched it up thinking it was be back to the same position - however I double--checked it today and was fairly far out :s Re-colminated now, lesson learnt too... Still you have to go through this sort of process of mistakes to learn how to do it properly. I don't suppose many people go straight to perfection with their imaging. Next time it's clear I'm going to try capturing this area for as long as possible, loving the shapes of these galaxies, absolutely fascinating! As for gradient exterminator, no I've never tried it. It looks like a paid-for photoshop plugin, is there a free equivalent?
  8. Brilliant photos there, can I ask, how are you guys getting that image scale, are you cropping or is it small sensors - I presume you're not all using really long focal length OTAs? I realise mine are a bit lame by comparison (I still don't know what I'm doing and worse, I realise all the shots I took the other night were through a tube that wasn't colminated - dah!!) Anyway, here is another. I like the shape on M81, might have to give this a proper go in the near future, see if some colour can be teased out.
  9. I believe it would allow that, allowing for other caveats like whether you might need guiding etc. I don't have/use a fork mounted setup so I'm not the best person to advise you on the details but the simple theory is putting a wedge in the fork inclines the axis so that it can have a axis of rotation pointing at polaris or more specifically the NCP - just like an GEM (EQ) mount does.
  10. you're better of with a P variant really I think (image quality wise and because at 900mm any tracking is going to be harder). The PDS is designed for prime focus, but it's not too hard to modify a P to achieve focus either. I think longer bolts cost 2.50. However, be aware the smaller focuser is a limitation (i.e. can't fit a coma-correctors etc) - had I have known this I've have gone straight for a 130PDS (or 150PDS) for large 2" focuser, at the time... Depends what you want to do, just to dabble at the Moon etc, then probably it won't matter to much, but prime focus is really what you want to get the best sorts of images of anything that isn't super bright like the Moon and any wide-field things (i.e. like M42 etc).
  11. exactly, for example I've just got a 5x barlow for next attempts at Jupiter/Saturn with video where previously I was using a 2x - so they have their uses. I'd definitely barlow the Moon if I wanted to get in close and see detail on a part of it. Coma correctors are for correcting the edges of a wide-field, you'd not use the two together, two different things.
  12. so in short, yes you can use one. In particular the OP said: "Only I would rather not have to buy a second scope if I wanted to do some close up pics of the moon or something!" and because the Moon is so bright this really is a place where a barlow can be used perfectly. In particular the Moon, planets and Sun (with suitable filters!) are ideal for barlowing. For example unless you have a high focal length SCT or similar most planets will be pretty small and a barlow in conjunction with a web cam will help scale the image up a bit. For anything DSO related, you could give it a go, but if you're turning your 5 minute exposures into 20 minute exposures you may have far more problems to worry about than the image scale. Best thing is get one and experiment, a barlow is always useful in the kit, you'll use it on the Moon and planets. For DSO what you might want more importantly is a coma corrector.
  13. yeah that's a good way to put it - in AP most times people require a reducer to speed things up, not a barlow to slow things down!
  14. inclining the fork will allow you to polar align, which then would allow longer exposures as the tube will naturally track with the motion of the night sky. Without, as a standard alt-az you're going to get field rotation which means longer exposures are unlikely to be possible. Shorter exposures and video of planets etc would be fine in either case though.
  15. I'm not familiar with the 6 but going from a 130mm (5.1") which is closer to 6" to an 8" was a massive difference visually, almost night and day! It's really those dim DSOs and nebula that it makes a difference on. For brighter things it makes less difference. The 8" is a good all rounder. Either would be good though. Depends on priorities. I'd always take an EQ mount if possible, esp. if any AP is on the horizon or you might collect different OTAs (lets face it, likely) and want versatility to swap then over on the same mount depending what you're doing.
  16. congratulations! and welcome too. I hope you get great use from it. I'm not sure I can recommend eyepieces, but you'll end up with several over time for sure, along with lots of other accessories Are you familiar with the night sky? Something like Stellarium is very useful for planning etc before you get out there with it.
  17. Where is the middle of the universe anyway, I'm not sure such a thing exists. What was the central point of the big bang (speaking causally here) is now effectively everywhere in the universe. Expansion happens everywhere, the universe is already too big to traverse at the speed of light in the time it's existed and bits are receding from other bits 'faster than light' - so we can consider it infinite in size, well at least until we invent that faster than light speed drive...
  18. I've had that feeling I've been staring straight at it before, just a sense of 'darkness' rather than seeing it properly. It's very dim, dark skies must be key, as people have said. I used to think sky permitting it was visible with the naked eye but now I'm not convinced, certainly not from our area anyway. I seem to recall there is some pattern of stars nearby, a spiral. I mistakenly thought that was it at first, now I realise that's not it at all! Not such a good time of year for it now, maybe autumn would be better when it's to the East early in the evening.
  19. Good question, I've wondered about this. I do a last scan before coming in doors, I try not to leave stuff scattered around outdoors so packing up is fairly easy. I do leave my end caps off. Last night I left them all off over-night as I was going straight to bed and figured better it all dries out properly at the slight risk of having no caps on, than I cap a wet tube. I've been leaving my OTA approx. horizontal until I cap it - I've wondered what is best here, should it in-fact be mirror up?
  20. thanks! yeah it makes you think doesn't it. So, I believe that type of supernova is about 1 billion times brighten than a normal star, so it will be as bright as the rest of the galaxy put together (approximately). I think I read the min safe distance from a supernova is 50ly, mind you not sure exactly what constitutes 'safe'! Not sure I'd fancy trying it out. We _might_ get to see Betelgeuse go, at just 600ly that will definitely be close enough for me!
  21. It's like anything, once you've found it you won't forget it, so consider it all good experience. The supernova is still really bright, here's one I took last night...
  22. This is the one I got from last night (Sunday 2nd Feb 2014). Still very bright isn't it! Probably brighter now than when I first imaged it on the 23rd I have some other images with M82 and M81 both in the same frame, will process and see how they turn out...
  23. you can but it slows down your setup so for example with a 2x barlow you might need twice as long exposures. In a world of perfect guiding etc (and unlimited time) then this wouldn't matter, but in practice it often does, a lot. However, for the Moon (or Sun, with suitable filters) these targets are so bright that a barlow is a possibility. Of course you might get CA with extra glass in the optical path. For DSOs etc you really want nothing in the path other than a coma corrector for a Newt (or equivalent flattener for a refractor)
  24. Hi, no problem. From what I remember the original was about 3 minutes, but it would have been several 3min subs, stacked (not that that made a huge difference but it might if you've much noise etc). At ISO 1600 IIRC Camera - Pentax K5 (APS-C) - all built-in NR etc turned off. Yes RAW, only use RAW, especially if you plan to stack or post-process, which nearly all astro needs/requires! Scope 130P (with moved primary so I can get focus) - no coma correct at the time Mount - HEQ5 Pro The last image I did is the same data, but I reprocesed and chucked in the 5min exposures I had too, which I think brought out some additional detail not in the original. I've very easy to lose M31 into the background, especially at the edges. Still that's probably true of any DSO. Probably next time I'll try to collect at least twice the data and hopefully really bring out some details. All a bit of a learning curve, including the processing side. I'd suggest, shoot many exposures, as long as you can until you get trails or light pollution kills the background. Shoot in RAW, turn all NR off. If you can take some darks too. Stack in Deep Sky Stacker Then adjust the result in something like photoshop, tweak the RGB levels and maybe the curves. Very few of my images start with a very dark background, processing helps recover it. Maybe if you live in a darker sky area you'll get better results from the start, but I'm tending to pick up light pollution when I up the exposure over 3-4 mins, about 6 mins is the most I've attempted so far, then it was something nice and high in the sky. Hope that helps! Good luck.
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