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libraryman

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Everything posted by libraryman

  1. First thing....you ra corrections are mostly on one side, that would suggest your pa is out quite a bit, your polar scope won't get you close enough. dec corrections point to a bit of backlash, if you are using Eqmod your tracking rate might be low, run the guiding assistant, it will help you. your dirty mirrors are unlikely to make a scrap of difference. actually, it looks like you are using an old version of PhD....update to 2.61 and ascom. 6.1 Ray
  2. Your rms is independent of your guiding arc sec per pixel ratio if you are reporting in arc secs, so...depending on your imaging scale..you should try to get half or less than half your imaging Arc sec per pixel scale. I.e. If your imaging scale is say..3 arc sec per pixel then a good rms might be 1.0 but really good guiding would be half an arc sec or just over I.e. 0.7 rms depending on seeing. some imagers do get less than this but it needs a very good mount and set up, the longer your focal length the more difficult it is to achieve. your Osc looks good at 0.35 but ideally you need to get your Dec guiding under control. The guide logs are in the PhD folder usually in c drive documents Ray
  3. That's not a good set up for guiding, I would say that your stars will be oval because you Dec rms is quite a bit higher than your ra rms. up the exposure to 2 secs if you can and perhaps lower the min motion, but......run the guiding assistant to check. Ray
  4. Yes the latest ver does appear to give a higher snr it's also correct to say lower snr is acceptable, however. Generally the higher the better it is, with 2.6.1 I was getting 20 the other night but 11 would also have been fine. I don't see low snr (5) as I used to with earlier versions Ray
  5. Good advice from Louise, i think she is trying to tell you that it's unlikely to be your choice of guidescope that's causing your guiding to fail, if you change to the 80mm you will no doubt have the same issue and then have the additional issue of setting up the new guidescope. Make sure you are focused and pointing in the general area of the scope, this will help when you polar align! The symptoms you describe sound like a lack of good alignment. But it might just be the camera losing the star because of thin cloud, look down to the left bottom corner for snr.. You need about 20...make sure you have the latest version 2.6.1 Ray
  6. Depends what you are imaging with and its focal length, I use a 7x50 Finder with my qhy5l-ii and its very good but my imaging scope is an fsq106 reduced to 380mm. the finder is light and very rigid if it's mounted correctly. The finder will need a small extension to reach focus but Bern at modern astronomy sells the adapters, far better than the st80 in my humble opinion. Ray
  7. I'm happy with my eq8, I have used it for approaching 2 years now, I have the eq8 tripod sitting outside all year around, when I see a clear spell coming I just lump the head outside and fix it too the tripod...it mght sit there for several weeks, I only remove it if I go away from home which I do regularly!! I have heard some comments about water getting into the encoder area's but I don't suffer any issues to press! I usually stick with 20min sub's but 30 min subs are doable, its just that I live on a flight path that puts me of longer sub's, as for reliability....... Perfect, no issues at all.....I have to admit that I had some Dec backlash and it took some adjusting out but that's sorted out now. Guiding performance is of course dependent on various factors but half an arc second guiding is pretty much the norm on a good night! I run an FSQ 106 and eventually I will run two on it, weight just isn't an issue but for me, a good aspect of the eq8 is its ability to carry loads of ancillary equipment on the head with it lots of flat surfaces....and that gives me good wiring options to keep it tidy..... It's a heavy beast but really good with eqmod, I never use the handset. Ray
  8. Run the guiding assistant, this will no doubt tell you that no backlash compensation will be required! Ray
  9. A really good presentation. time well spent Ray From sunny but light polluted Phuket !!
  10. I don't use a star alignment method to polar alighn, rather I prefer to use PhD..however you choose to do it; it is I feel important to understand exactly how far your mount is from being truly aligned, in that sense I prefer to be no more than 1arc min from perfect alignment! This level of p.a. is quite accurate but it does allow you to explore the longer sub's without rotation issues and gives you the best start for good guiding. Ray
  11. The Heart Nebula, its taken me quite a while to collect the data for this, its not been too fruitful a year! Ray
  12. Merry Christmas Tim, best wishes to you and SGL members for the new year. Ray
  13. Plus 1 for Michael's comments, sometimes it's better to set up on the bad nights just for the setup experience and practice! It's taken me 2 years to acquire what I want and a method to use it .....repeatability.....is my watch word. Having said that....recently I set up and in my attempt to get up and running I completely forgot to polar align!!! Some couple of hours later, I realised that I had forgotten. Doh.....age does that to you but I still wouldn't give up. Ray
  14. Cheers folks....I recon I'll see you at the next meeting Bob. Ray
  15. Thank you for your comments all, I have to say this is my first attempt at a comet and it was purely guess work! I took 2 x 120 sec sub's initially then decided that might be too long so I changed it and took some 40x 30 sec sub's after reframing it..... When I came to process it, of course it did not like the combination of two different times and framing but I followed the Harry Page video for comet stacking and pleased I did... It took me a good few hours to follow it correctly but at last I had an image I am particularly happy with.....thanks Harry I will eventually run DBE on it to remove the daylight gradient top right... Ray
  16. Took this on Monday morning just as dawn approached..i managed to capture a few galaxies as well so quite pleased! Ray
  17. The one setting in eqmod is the guide rate....it defaults to 0.01 I think but its best to change that too 0.5x Ray
  18. Hi, hoping some expert will help me with a stacking question I'm trying to stack a good few subs of Catalina taken last night...I'm new to pixinsight having previously used Images Plus. If i use images plus to stack; i can use an align feature that allows me to use the comet head a an alignment point...this of course trails the stars...to be sorted later !!! Is there a similar function in Pixinsight ??? Ray
  19. I see as interesting, as I see most targets, I guess we make these comments because we think they are imaged to death but its a cracking image. Ray
  20. Cheers for the link, clearly I can use the O111. Ray
  21. I'm grabbing O111 on the jellyfish nebula, is there much to be had or is it just better to stick with HA? It looks farther weak, A 20 min just shows a bit on the edge!!! Not tried Sulphur yet but I'm at 17 x 20mins on the O111 does Sulphur add much to the nebulosity? Ray
  22. Very nice image, lots of detail and sharp Ray
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