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Mr niall

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Everything posted by Mr niall

  1. oh no its worse than I thought, it got so red that they changed it back to white... I suppose the moral of the story is that I would kill for 3/4 skies 😉
  2. Wow, Bortle maps of where I live look like a badly sunburned goldfish...
  3. amazing work, that's some serious dedication
  4. Just an update - ended up buying a skywatcher mercury 607 (60/700) on an AZ2 with finder, 2x eyepieces and barlow that I found brand new on ebay for £48 , and an explore scientific white light filter for £18. So £66 spent so far... Will report back.
  5. Yes but they’re so low it’s frustrating. I saw Jupiter through an 18” dob in the alps a couple of weeks ago it was like looking at a bowl of Angel Delight at the other end of the table 😜. After 5 minutes had just about made out 6 bands. No festoons.
  6. All good points sir, but I think we may be drifting away from the original aim which is to get up and running as cheap as physically possible. The way this conversation is going, I believe by the time this thread has run it’s natural course I’ll be purchasing a Quark to go on a Tak100 and mounting it all on an eq6... 😜 The 707 frac you showed me is very nearly twice the price of the mini dob - but from what you suggest I think it will provide double the experience so that’s ok. After that, well we’re getting into diminishing returns territory. If I enjoy it I’ll probably get a solar scout or PST as they look like a lot of fun but that’s some way down the road and I kind of just want something as cheap and straightforward as at all possible at this stage...
  7. lovely looking scope - that might be just the ticket.
  8. Thanks all - I think that probably confirms the niggles I had about using a scope as a projector, I think I’ll probably steer my ideas back to the safety of either a filtered scope or a traditional projector. now... small frac or small reflector 🤔🤔
  9. Thanks - as feared there appears to be lots to consider! I will admit that projection would be a more appealing route if it offers a similar resolution to just viewing through baader film straight to the eyepiece. but I must admit I am a little nervous about the whole “pointing a scope straight at the sun” nature of it. Is it not a little bit dangerous? In my naivety and accident prone history I can’t help but feel that there’s a relatively high chance of me injuring myself or burning down the neighbourhood. I’ve accidentally started a fire with an uncapped 6x30 finder before and it was fairly frightening! And there’s kids and dogs at home that will no doubt “get involved”. Or have I misunderstood the projection concept? Theres an evostar 90 Ota with diagonal and eyepieces on astroboot for £75 at the mo - do you think that’s more the sort of thing I should look at? apologies again for the daft questions!
  10. Hello there I'm trying to create the worlds cheapest white light solar setup. I'd toyed with the idea of getting the astromedia solar projector which looks quite cute and seems to work looking at the reviews but then was wondering if there was any fundamental reason why the heritage 76mm with a baader film wouldn't work equally well? https://www.firstlightoptics.com/all-telescopes/skywatcher-heritage-76-mini-dobsonian.html Or am I missing something obvious as I cant see anyone has ever actually tried it. I'm aware the people have done it on the 114p virtuoso so I guess its feasible. I'd really like to get into tracking and sketching sunspots so I'm thinking a classic projection setup may be fun but not quite have the resolution I'd need for quality sketches? Sorry if these are daft questions, solar really is a completely new area to me.
  11. How longs a piece of string?? 😉 Depends primarily on the age and condition of the scope, particularly the quality of the mirror. The same goes for the eyepieces; none of them sound particularly premium although combined would make a fairly useful set. Camera quite a good one though provided it has all its bits and bobs. Possibly worth as much as £75-80. As for the rest... a good 10" dob can usually fetch around £225 if its in good condition. But depends on condition. I'm not sure the combined price of the rest of the accessories would command a high price. You're usually looking at half to two thirds of retail for well looked after equipment. Not sure if that is much help.
  12. I bought the helios mistral WP6 10x50 ED from FLO for £125 a few weeks ago. I was dubious about the ED claims for that sort of money but was tracking circling buzzards and eagles across the Alps for the last three weeks and there was an unbelievable level of contrast and lack of CA against any background so I would guess its certainly achievable at that price point although I don't know how. I did notice a slight drop off from about 85-90% out but compared to something like the Pentax ZD ED 10x50 I didn't really experience a noticeable difference. I really don't understand the economics of binoculars!
  13. Hello all Probably a daft question (stupid boy!) but I've been pondering the effects of ISO on DSLR imaging. Due to my roaring ineptitude I limit myself to relatively short exposures with a wide lens (recently bought the canon nifty 50 based on recommendations here and what a lens!) but I'm aware that wide field exposure in suburban / rural areas is often limited less by accuracy of setup and more by the blowout caused by light pollution. The advice I have always received is to lower the ISO to compensate for this and therefore still obtain longer exposures. And it is this I have been pondering. I understand how ISO works (at a rudimentary level probably) and obviously that in its most simplistic terms its analogous to increasing the sensitivity of the sensor at the expense of introducing noise. I quite liked the way that somebody explained to me once that it was similar to the "gain" control on a guitar amp; the way you can dial it right up but eventually it just becomes a distorted smush (mine goes up to 11!!). My question is (sorry took a while to get there) is that does taking a longer exposure picture at a lower ISO provide a fundamentally better picture than a short exposure picture with a higher ISO? I'm not talking extremes here - I normally work in the 400-1600 ISO range and with exposures from 20 to about 120 seconds. But what I'm wondering is; when I'm getting LP blowout at say 90 seconds with 1600 ISO should I be: lowering the ISO to preserve the exposure length? lowering the exposure length to preserve the better level of sensitivity. afforded by higher ISO? How would those changes fundamentally impact the image? I don't dither or bin, I just stack and stretch, and I always take darks (but I rarely take flats as I just can't seem to get them to work at really short focal lengths). Any insights appreciated. Many thanks all!
  14. Nope never heard of sky at night until long after I joined this forum. Patrick Moore was always the games master to me!
  15. Yes good point - but I was hoping to hit something in the f2.5 to f3 range which it looks like is easily achievable. My kit lens at 55mm is 5.6 I think, so yes trying to significantly improve on that as an attempt to mitigate my rather slap dash and incompetent attempts to polar align and track! 🤪
  16. Yeah… do you know that never occurred to me until I started this thread! I've always shot wide open and wondered why I'm getting such bloated stars with my 75-300. I always assumed it was either a focussing issue or a tracking issue (which it probably was as well) and I know the 75-300 isn't, objectively speaking, a brilliant lens that has its own issues; but this thread has really opened my eyes as to the importance of using a more conservative f stop. I love this place! 👍👍
  17. The 120 is a cmos not a ccd but yes you're on the right lines. DSLR and CCD imaging are fundamentally identical - but if I'm reading your post right I'm assuming you are taking ccd imaging to mean planetary imaging. Planets are bright - so they don't need long exposures. But they're small so they're more sensitive to atmospheric wobble and fuzziness; just as when you look through the eyepiece and see planets change shape, colour, contrast, clarity and sort of wobble around. So, because they are small you don't need a large DSLR sensor as 99% of the sensor is looking at nothing, a smaller one is better. In the same way that a small eyepiece creates a more zoomed image, the same is true for camera sensors - so a smaller sensor is a double plus in that regard. Additionally one that is extremely sensitive is a plus. And that's fundamentally the difference between a DSLR and Planetary camera (not CCD - they can have sensors that are all the way up to full frame in size) a good planetary camera has a very small, very sensitive sensor. Resolution is largely irrelevant; as above - Jupiter at its biggest is only 49 arc seconds across so that's only going to take up a couple of hundred pixels at most; there's literally no point having a 24mp dslr sensor pointing at it as 99% of the pixels will see nothing. The other reason that this is a plus is the fact that you don't actually photograph planets, you video them. Because of the wobbliness described above you have to take many many short exposures of a fraction of a second. Really at least 200, but as many as 5000 through a video recording. From that you review every single frame if possible, discard the poor ones and keep the good ones. You have a choice of processing these through something like Autostakkert!2 or Registax (both free) and it stacks these all together as with traditional DSLR photography and voila! That is a very very short explanation but should give you the idea. There are lots of guides on google. (all that being said, you can take good planetary images on a DSLR, especially if it has a 1:1 crop on lower res videos (which few have these days sadly) but the main point here is that planetary imaging is a different discipline to long exposure short focal length astrophotography) Hope that helps edit: here is a pretty good guide that does a better job of explaining it than me http://www.star-hunter.ru/en/planetary-imaging/
  18. Thanks all - following advice I've managed to picked up a new Canon EF 50mm (the newer STM version) for £89. I'll be quite honest and say the price was the deciding factor over the 40mm which does look lovely but at £89 that represents pretty brill value for money. If I can get some half decent subs from this then the longer term plan is to pick up a Samyang 135mm but that is a significant jump in budget and focal length so the 50 will doubtless keep me going for a while! Will report back with findings.
  19. wow that is super useful - can see a massive difference between f1.8 and f2.8, that would probably be good enough for me (I'm nowhere near competent enough to approach the limits of equipment under even moderately normal use so can't see that being a limiting factor!)
  20. You wouldn't happen to remember what the review was called would you (I must admit I'm a real sucker for pancake lenses. I used to have the M-fit pancake on my old eos M1. What a lens...)
  21. wow those are some sharp edges. Shame you have to go down to f7 though. Although I guess at £80 its not fair to complain.
  22. Hello there Can anyone recommend a good cheapish fixed lens with a standard Canon fit in the 50-100mm range? I've noticed there seems to be a fair few nifty fifties out there but I'm not seeing a huge amount of info on edge sharpness or distortion that seems to be the bane of my life with my otherwise excellent 18-55 kit lens. Ideally I'd like to be hitting around f3 or lower too if I can! Thanks all!
  23. This was touched on in a thread a couple of years ago may be of some help:
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