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BrendanC

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Everything posted by BrendanC

  1. @vlaiv OK, so I've taken the sky flats - and just realised, I don't know how to stack them! All my stacking programs want to find stars in the subs, obviously so that they can be aligned etc. How do I stack essentially flat, blank subs?
  2. So, I'll keep an eye out for dew/frost too. I'm going to habitually start using the dew shield from now on, as well as flocking it. I will also be trying out the ASCOM drivers. I'm also going to have a run with no filters at all (I have a spare empty slot) to see if that has any effect.
  3. Thanks - and I do have more data, as per my earlier post (see https://stargazerslounge.com/topic/395577-asi1600-and-130pds-about-to-give-up-need-help/page/3/#comment-4251560) Regarding total integration time, my thinking was that I could actually do LESS time. The Bayer matrix determines that I would have 50% green, and 25% blue and red. So, for mono, I could therefore shoot, for the same amount of green, 75% less red and blue. I've been shooting Luminance and then the same amount total Lum as RGB, but with individual subs for RGB at 3x Lum. So, for example 3 hours of total exposure could be 1.5 hours of, say, 60s L, and then 1.5 hours of 3x30 minutes at 180s of R, G and B. Given the higher resolution and generally better, more sensitive response of the ASI1600, I thought this would result in a better image. But I was wrong. Again. I think I have a plan now though. Thanks again for all your help.
  4. @inFINNity Deck OK, so I like charts etc, but if you could please tell me: What do you think the problem is? I don't know what an SQM value is. What is the most likely solution? That would be really helpful! Thanks. Brendan
  5. I'm using the native drivers. What changes would the ASCOM drivers offer? Ideally I wouldn't need to learn a whole new package, but I know NINA is very highly regarded. Perhaps you're right - just throw everything into the air and see what lands.
  6. Thanks again Vlaiv. I can confirm there were no flips involved, so it looks like this is not related.
  7. Thanks - I cool it at the APT default, which is something like 3 degrees every 2 minutes or something, with a pause every now and then. I'll see how that goes.
  8. Agreed - and that's why I said 'somewhere along the line'. I meant that the camera should be fine in terms of suitability with my system, regarding sampling and guiding. I'm assuming the camera is fine, it's something to do with the OTA, the environment, or my calibration/processing technique. Again, thank you so much for your help Vlaiv. I'm learning so much through this, most of it about how I'm doing things wrong(!), but it's all learning.
  9. Thanks. The quality of the camera is in no doubt. It's just been a case of trying to figure out what on earth has been going wrong with my subs/calibs. I'll look out for fogging/freezing.
  10. Could you provide a link please? There are lots of options!
  11. Indeed. OK, well, thank you @ollypenrice and @vlaiv for all your help. I'm going to flock the OTA, and try to change my flats method, but this is proving an exceptionally painful experience. I did quite a lot of research and thought the ASI1600 would be ideal, but it's increasingly emerged that something isn't right somewhere along the line. Thanks also to everyone else who's contributed.
  12. @markse68 How far do you take your panel from the focuser? Do you place it on the dew shield, or further away than that?
  13. True, except that it didn't - it started at 23:00.
  14. Thanks, but I'm a bit cack-handed with anything remotely DIY and I like the idea of the acetate sheet method, particularly getting my hands inside such a small area. Would this be suitable: https://www.amazon.co.uk/Vesey-Gallery-Acetate-Sheets-420x297mm/dp/B07SSLQ9RB/ref=sr_1_18?keywords=acetate+sheets+a3&qid=1654535861&s=officeproduct&sprefix=acetate+shee%2Coffice-products%2C59&sr=1-18
  15. Hi, I know this is an old thread but I'm considering doing the same with my 130PDS to possibly cut down on internal reflections. @Craig a, do you have links please to the flocking paper you used? Also, if you used the acetate sheet method, and it was successful, do you have a link to whatever sheet you used too? Thanks, Brendan
  16. OK, thanks for this Vlaiv. It's very informative. Finally (?), for @ollypenrice, here are two versions of the lum subs, stacked in Siril again, one with flats/dark flats, and one without flats (but still with darks). I'm sorry but I don't know how to do a log stretch, so please feel free to take these images and do whatever you need with them. I was going to attach them as JPGs but thought it best to use the original FIT files, for integrity. Apologies to Olly if this is a bandwidth hog (but surely 65MB isn't a huge download?) So situation so far is: There may be a light leak from an unknown source - I'm going to wrap the OTA as a test and see if that helps, and consider properly flocking the inside too I should try and create flats that are >1s and with >1s between each frame (I currently have 1s pause between each frame) - and I should be able to use paper or some such thing to dim the lightbox sufficiently to do this I should place the light source further away from the OTA - not entirely sure yet how I'm going to do this, as in getting the light source and OTA aligned, but I'll have a go I'm also going to add here that it also seems I need to be much more selective with my subs, particularly when there's a lack of proper astro dark in the UK Is this about right? And if I continue to bang my head against this particular rock, I also have in reserve the notion that I could go back to an OSC, probably a nice simple ASI533MC or some such thing. without flats.fit with flats.fit
  17. So does this mean that the bottom right corner is showing an external light source leak?
  18. Right. These were stacked in Siril because it's soooooo much faster than APP. First half of lum subs in 1.fit, second half in 2.fit, same calibration files used for both. There is quite a difference. What does this tell me? That there is a light leak? Or that the sky is sufficiently different on one side of the sky than the other? Or that I have internal light problems? Or my flats are over-correcting? Etc. @ollypenrice and @vlaiv, over to you guys cos you're the gurus helping me through all this. 1.fit 2.fit
  19. ... and I'm starting to get that panicky drowning feeling again. @vlaiv, I'm going to do as you suggest - split the lum files into first and second half, stack with same calibs, and share here. Simple next step, will take me forward, and allow me to decide on the next step (which could be a different camera altogether, this is driving me crazy). In the meantime I've just been a bit ruthless with removing subs that looked a bit too bright using PixInsight's blink feature, which were overwhelmingly from the first, what, 30 minutes at least of each of the three nights' data I have in total. This is from about 2.5 hours lum, and 1.25 hours each of R, G and B. The results are a bit better, but as with all my other images, they're in spite of the data rather than because of it. I will however be putting them back IN to the stack for the above test.
  20. Thanks again Vlaiv. Given what I've been going through, I'm thinking it's probably the 'something strange' option. What I still don't understand is why I was doing fairly long shoots with the DSLR without this problem. Next shoot, I swear I'm going to wrap the OTA in foil, to try and mitigate any sort of possible leak, and take it from there.
  21. Thanks Olly. Honestly, I wouldn't even know where to begin doing this, however. Plus, I don't know whether I want to, especially not for every shoot I do. I've taken flats every which way, and stacked using Siril, DSS and APP, and still don't know why this is happening.
  22. So, the state of play now is: The scope isn't up to the job The flats are over-correcting The flats need to be >1 sec ... in addition to the first set of bullet points I listed. I don't really feel I'm much closer to a solution. Let's say I stick with the scope, and want to fix the flats: Am I right in thinking that I can reduce the gain/offset to zero to try and get longer flats, even if this is different from the subs? Also, if I have to resort to putting sheets of paper in front of the light panel to achieve this, will inconsistencies in the paper cause artefacts in the flats? Let's say I stick with the scope, and want to change the camera: What do people think my chances would be of getting better results with an ASI533MC which is looking like an increasingly attractive alternative?
  23. Ah, I see what you mean. I have a hat over the end of it now, very similar to how you're set up. Have had this arrangement for quite some time now. I think I've probably already tried that (I'm losing count of what I have and haven't tried), but I'll try it again. Like @vlaiv, I do not know how I can achieve this. Thanks for this but I'm afraid I'm confused (again) - does this bear out what Olly's saying about over-correcting flats?
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