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oldannie

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Everything posted by oldannie

  1. Still trying to sort out the reasons for the star trailing with Ha subs . On the first occasion I took 24x600 sec subs in Ha and around half suffered from star trailing. At the next imaging session I took some 600sec RGB subs with no signs of trailing. Next session I took 12x600 Ha subs (nothing else) and 8 out of 12 showed trailing stars. The first two subs were ok and the last two almost ok! Last night I took solely RGB subs and no trailing. Have checked for signs of anything obvious in my cabling/connections and will download the PC application for my guide camera so I can record a guide log next time but in the meantime is there anything else I need to consider - is it just coincidence that the trailing has only occurred when I take Ha. Star trailing is not something I have encountered until I moved from DSLR imaging to CCD imaging. Annie
  2. Thanks Tony - am hoping it is the most obvious cause - snagging cables. Annie
  3. yes Dave - I've had the guider for a number of years now and it's been great - I do wonder if it's something simple like cables pulling as I'm not used to lots of cables! I think recording a guide log on the mgen is easy it will be working out which driver to download and how to download it but am sure I'll get there. Carol - I don't think it was particularly windy that night but I do think cables pulling would be a logical reason. I was so busy checking my guide star was there that I forgot to check how the cables were doing!! Don't think there will be that much detail left when I eliminate all the bad subs. Learning a lot though. Thanks folks Annie
  4. Just seen your reply - I agree it's definitely a guiding problem - not one I've had before! Happy with the background - thanks for that. Annie
  5. Thanks to 'Oddsocks' for recommending Avis Fits viewer I've been able to look at all my Ha subs. The files are numbered sequentially ....595 to ....614. The first two are fine; 599 shows bad trailing and nos 601-606 show trailing also. Have not experienced this before with my guider though only recently started using it with a CCD . What might have caused this? I can record and download a guiding file from my guider but need to download the PC application first. Annie
  6. Thanks Dave - I didn't think they were right. I'll check my individual subs. I think the Lacerta guider does enable you to record the guiding and presumably produce a graph but in order to keep things simple I have avoided it. Something else to learn how to do next time - it seems pretty important to be able to look at the guiding. Lots of things have gone slightly wrong with my first attempt at CCD imaging but other bits have gone better than anticipated and have learnt a lot. I'm not very technically minded so it's all a big challenge but an enjoyable one - well most of the time ? Annie
  7. Thanks Dave. Some of the stars look as though they have a 'pimple' on the end but perhaps what I'm seeing is just smaller less bright stars very close to brighter ones - if that makes sense! In other words I'm seeing stars! Annie
  8. Thanks for your reply Richard. My broadband speed is low (2/3mps) so I have difficulty posting anything other than jpegs and have tried using Dropbox but again the low broadband speed makes that difficult. I did check all my calibration files and couldn't see anything obvious so sent a jpeg copy of my stacked Ha to Carol (a regular in SGL) and much to my embarrassment it has turned out to be lack of skill in processing that has been the problem!!! Still I've learnt a lot in the process of finding that out! In the past I've tended to ask before I've allowed myself sufficient time to think through the issue but I take your point about advice being readily forthcoming and have already experienced that. Here is a copy of the stacked and processed Ha data - 25x600 secs using Takahashi 106ed: Atik 460es mono: stand alone mgen Lacerta guider on neq6. Hope the 8bit jpeg image appears ok - just under 500kb! Do you think the stars look a bit odd or am I being pedantic? Thanks again Richard Annie
  9. What a lovely shot. It's very easy to overdo the color but yours is just right - love it. Annie
  10. Couldn't wait til tomorrow to check Avis - works fine!
  11. Have downloaded and installed Avis ok and will have a proper look at it tomorrow. The link above to 'Fits Liberator' was the one I have been using and I still had no joy with it. It appeared in my C drive and the manual opened ok but when I tried to open the application it took me to something entirely unrelated in my D drive - very strange! Many thanks for the replies - much appreciated. Annie
  12. At the moment I use DSS to stack and photoshop cc to process. My mono CCD produces fits files which won't open in ps. Though I can stack and convert to tifs in DSS if I want to look at individual fits files I have no way of doing that so have been trying to download 'fits liberator' to my windows 10 laptop but having difficulties and not sure why? Annie
  13. Yes you're right. Am def going to check my calibration files. The Ha flats were taken at around 24000 adu's so that part should be ok but I do take your point about stray light and think I might need to be a bit more careful about that aspect. Thanks Annie
  14. I think that's very good advice and in fact I thought maybe I'd posted a little prematurely (ie. before I'd thought it through properly!!) I have already tried it without any calibration files and it's quite a bit better so am going to go through my calibration files as you suggest and also my light subs. Much appreciated. Annie
  15. Am trying to image the Crescent Nebula as my first image with a CCD camera having just moved from DSLR imaging and realise I am quite ignorant about some of the basics. Having collected some RGB subs, stacked and aligned in DSS using a red channel sub as reference image I have managed to generate a color image in photoshop. Last night I took some Ha - 25x600sec using Atik capture software, Artemis. When I lightened the first sub in Artemis it looked great with lots of detail - a wow moment! This morning I stacked and aligned in DSS using the same red channel sub as reference image together with darks, flats and bias frames and as is often the case the result was a quite dark image. Opened it in photoshop expecting to reproduce the same detail I saw on my computor screen last night but it still showed very little detail and soon showed signs of over - processing when I tried to use levels. As is oft the case with this hobby have gone from euphoria to disappointment in the space of 12 hours!! Have I missed something obvious - it wouldn't be the first time!! Using Takahashi 106ed, Atik 460ex on neq6 with lacerta mgen stand alone guider. Annie
  16. That would seem to be a sensible compromise Carole - Cheers! Annie
  17. I did wonder about the efficacy of darks Olly and no I would rather not go to all that trouble. - does that mean you just use flats and bias. I would expect to take around 20 flats and loads of bias? Annie
  18. And I can run it for say seven hours non-stop?
  19. I want to collect some 600sec and 300sec darks, maybe 20/30 of each over as short a period as possible, using Atik 460ex, mono. I have my cooling set to -15 deg C (max for the 460 is -25) and the weather forecast is telling me it's going to be about 8 deg C overnight though as we're quite high and rural it may well be lower. Using the sequencer on Artemis capture can I safely let everything run for 6/7hours (in my pulsar) or would I be better acquiring darks over shorter periods? Have only just moved from DSLR to CCD and not overly technically minded so full of naive questions! Annie
  20. I think so Carol but will make sure I do when I start from the beginning again! Annie
  21. Thanks for that 'Sub Dwarf'. I seem to have cracked the process of generating a color image from RGB but still have no idea about the 'swatch' of color which appears on the blue and green stack and hence on the merged RGB. Have taken a new lot of flats (though don't think flats are the cause) and am going to re-stack and perhaps try one less green sub and one less blue sub to give me R 600sec x 9, G 600 sec x 5 and B 600 sec x 8 though again not sure this will have much effect. Also yet again check my settings in DSS and then will have tried everything I can think of. This was my first image using a CCD camera and am a bit worried that the color swatch is going to appear on subsequent images if I don't discover the cause now. Imaged using: Takahashi 106 ed, Atik mono 460 ex and stand alone guider, Lacerta MGEN.
  22. I'll go back and look at all three channels as I recall this issue crops up on two channels but can't remember which two - I suspect it's the blue and green. I have been thinking of downloading Hasta La Vista Green so will do that. Am also intending to add some luminance data probably Ha - something else to get my head round - but would like to sort this issue out first. Thanks Olly and for the comment 'lovely result'. Annie
  23. Managed to stack and align RGB subs in DSS and generate a colour image in photoshop. This was my first attempt at imaging since moving from DSLR to CCD, using a Takahashi 106ed, Atik 460ex, mono with Baader filters in the Atik EFW filter wheel. Target was the Crescent nebula and I took R 9x600sec , G 6x600sec and B 9x600sec, stacked with darks, flats & bias frames. Have started to process in photoshop, though not very experienced at processing. Have not got very far when I noticed an odd patch of colour along the bottom of the Crescent, mainly centre right. I maybe should have posted this in the imaging forum though perhaps the problem lies with my mediocre attempt at processing! Not sure what the parameters are for attaching images so hope this works! It's 521kb JPEG . Annie
  24. Thanks Alan and Gav. It turned out to be a wrong setting in DSS!! The whole process worked as it should once I had tried changing various settings in DSS and settled on checking something called 'background calibration' (well called something like that). Thanks for all your responses - much appreciated. Watch out for more naive questions from me! Annie
  25. All three are grayscale. It must be something so obvious it's not obvious!! Am going to take my laptop and files over to a contact (newly discovered) who says he has had success using this straightforward method. If we can't work it out watch this space. If we do sort out the problem I'll post the outcome. In the meantime thanks for your responses Gav - much appreciated. Annie
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