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About DKNicholson

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    Star Forming

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  1. DKNicholson

    D K Nicholson

    Images taken over ten years or so - so far! Until 31st October 2019 all the DSOs were taken using an Atik 314L+ camera through various telescopes. Planetary - when added - will have all been take using a ZWO ASI120MC througha Meade LX90-8".
  2. Many thanks indeed for clarifying the process and associating it with the camera that I have - very helpful indeed. SGPro does have a histogram function so I can certainly use that. As our weather is currently cr*p then I can do something about darks and bias frames, something else I hadn't thought of! As it happens I don't have PI but DSS will create master files so I should be able to use that functionality. Thanks again, much appreciated.
  3. Thank you kindly for trying to explain. Sadly I feel none the wiser as, for some reason, I am not comprehending the terminology or how to measure/establish 'target average ADU' and 'non-linearity in pixels'. I concur with your comment 'may be tricky to calculate' as I have absolutely no idea how to do that. I like your idea of positioning the flat panel in the obsy - I hadn't considered that and it would not be difficult to sequence that into SGPro so that all the flats were done at the end of the sequence. The camera I have is renowned for not requiring dark frames - it's a high QE CCD. As for Bias frames I believe a library can be created which is periodically updated, so that is something I should do.
  4. For some years now I have been very lazy when it comes to flats and have rarely done them. Recently I created a library of flats, but when added the files to the lights in DSS I lost not only the dust bunnies and other artefacts but also some of the details of the DSO and the 'sky' became very 'flat'. Plainly I was doing something wrong. I had made a Flat Panel with variable output and put some opaque white sheets in front to ensure the light was even. The camera at the time was an Atik 314L+ with full-well of 19,500. I've now changed the camera and wish to make the best of it. Now I have a Starlight Xpress Trius SX694 Mono and the Full-well is stated as greater than 17,000 and system gain of 0.27 electrons per ADU. How do I establish the correct exposure time for flats? I shall be needing LRGB and Ha, SII & OIII 1x1 binning and RGB 2x2 binning. I use SGPro and it has a Flats Wizard but it needs to know the exposure range to use - and thereby hangs the problem. How do I establish that range? For those who use SGPro, is it necessary to create flats during the imaging sequence, if so how? Besides manually placing the light panel in front of the telescope after each filter, I cannot see how to do it - particularly as I work remotely and a flip-flat is out of the question (£££)! Any 'simple' help with this knotty problem would be greatly appreciated - not only be myself but by many others I suspect!
  5. Thanks for that, I've Just ordered one - seems like a reasonable solution.
  6. Not sure what's happening there as I have 3 laptops and a desktop which I always keep up-to-date and have never had a problem. I do wonder if perhaps that is more something to do with Internet Security software than with Windows 10.
  7. For what it's worth, Windows 10, that was much maligned when it was first released, is probably now the most versatile and stable version of Windows they have ever produced. That's probably not what a lot of people want to hear but it really has evolved to being a very good OS - and I don't even work for Microsnot!
  8. My first imaging 'scope was a William Optics Zenithstar 80 doublet and using it for Ha Narrowband imaging onto an Atik 314L+ (CCD) it was just fine - BUT (isn't there always) it had its limitations. Whilst it was a very good doublet there was still noticeable chromatic aberration when imaging particularly in LRGB. On that basis a triplet would certainly be advantageous if it will fit into your budget and you feel you may become enthusiastic over astrophotography. As for the mount, personally I should recommend you acquire an HEQ5 Pro Synscan as that would serve you well for some time to come and it is easy to guide. Until very recently I was using one to image with an Altair Wave Series 115 with a separate guide scope. Whilst that was fairly close to its viable limit it performed very well. It is quite easy to start with equipment with which you become quite quickly disillusioned. Buying 2nd hand is your best bet if you are thinking of dipping your toes in to see if it's an activity that may or may not interest you in the long term. It can quickly become a very absorbing interest - and then it can start to become expensive. Therefore if possible you want to try and avoid buying something new that you then may need to replace in the near future. As you will soon discover - everyone in this 'hobby' has their own and differing opinions and that can either help or confuse the issue hugely. I only offer my opinion from my own personal experience and just hope it helps to clarify a little and not confuse too much! I wish you and your bank balance all the very best in this compelling activity. Yours aye - David
  9. I'm using an Altair Wave Series 115 refractor with a Starlight Xpress Trius-694 camera. The guide camera is a Lodestar x2 through a TS-50 and Barlow x1.5. The image from the guide camera is very good and the ratio of guiding to imaging is 1:1.6 which I understand to be quite good for this set-up. I do have an SW ST80 where the ratio is 1: 2.2 which is OK, but the clarity of the stars is not particularly good. Using the TS-50 on its own pushes the ratio a bit far and the image through the Barlow and TS-50 is better than that using the ST80, so I've settled on that for the time being. The photosites (pixels) are the active cells on the chip and PHD2 seems to presume they are square as there is only one box available to enter the size. The Lodestar x2 has rectangular photosites (pixels) that are 8.4um x 9.8um. For some odd reason I had this set to 8.0um, but have now set it to 9.1um as the mean. I'm currently waiting for some clear sky to recalibrate PHD2 and run the guiding assistant. If I can get the RMS total error below 0.8 then I should be a happy bunny. David
  10. Louise hi - That is pretty much as it is balanced at the moment and everything is absolutely rigid. I have found a couple of settings in PHD2 that may help a little. Whilst the image of the main camera and the image of the guide camera are similar, it is plainly evident that it is better if they are carefully centred on the same object. Also the photosite size of the guide camera was not accurate whilst the focal length of the 'scope and Barlow X1.5 is! I should also calibrate again and see if that helps - otherwise it's a bit of a mystery! David
  11. Louise - Thank you kindly for that. I have an EQ6-R Pro which comes belt driven, so it would seem that should have removed most of the issues. My concern is with guiding and I find the graph does jump around more than I expected. Whilst I know there can be various reasons for this, I have never applied any bias to balancing - except perhaps slightly camera heavy (refractor) and I had wondered therefore if balancing might be part of the problem. David
  12. Louise Hi - With the telescope etc in the home position pointing very near to Polaris, I should be most grateful if you could explain to me what is meant by East Heavy. Don't worry - I have just found an explanation elsewhere in the forum!
  13. Having read through most of the posts there were two things that I noticed that seem like very good ideas. There are two very distinct parts to Astrophotography - the image capture and then the post processing. It is fair to say that both are an amazing challenge. Someone mentioned the book 'Make Every Photon Count' and that is certainly an excellent book for both aspects and is highly recommended. Another item mentioned was the SkyWatcher Star Adventurer. If you can pick up one of these 2nd-hand it suits a DSLR and lens very well indeed and the tracking is excellent. As it is very portable you can keep it and use it even when you have upgraded your telescope and mount. I am lucky enough to have a lot of different equipment, but I still have a Star Adventurer and it's an impressive device. The attached image was taken using a DSLR and lens mounted on to it, then post processed to accentuate the asterism - Kemble's Cascade. BEWARE, this is an addictive hobby and for once the adage is perfectly true - when it comes to expense 'the sky really is the limit'! It has just occurred to me that Stellarium is free planetarium software for a computer that would certainly help you find your way around the night sky and find objects to view and image. As has been suggested, I should be inclined to use your current telescope and mount for observing.
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