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Adreneline

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Everything posted by Adreneline

  1. Thank you Peter. As per my response to @Peds I prefer a more subdued approach to my images. I tend to think space is dark, dusty and not very friendly with odd pockets of colour so I like that to come across in my images. Glad you like it. Adrian
  2. Thank you. Glad you like the colours - I tend to prefer the dark, dusty and slightly menacing look 🤣. I used the Astronomik 1.25" 6nm SHO filters. Yes, it is SHO but I remove all traces of magenta and all but 5% of the green cast - personal preference. Adrian
  3. Two clear nights (!!!) and 7+ hours of data using the RedCat 51 with ASI183MM-Pro; calibrated, register and integrated in APP and processed in PI using the Xterminators plus a bunch of other PI processes. Annotated: Thank you for looking. Adrian
  4. Thank you Peter. A greyscale Ha image has a beauty of its own - which can be easily spoilt by a dose of bad OIII 😆. Adrian
  5. WIth the weather we are currently enduring I am happy to settle for a decent amount of Ha data to make a two-pane mosaic; each pane is 12 x 300s taken with a Samyang 135 at f3.0 + ASI1600MM-Pro + 3nm Antlia filter. Annotated: Mosaic assembled in APP, processed in PI. Thank you for looking.
  6. I am trying to get my head around de-centring. How is it possible for the sensor not to be central with the OTA axis assuming (a) all the connecting adapters are concentric, and (b) the sensor was centred correctly in the camera body at the time of manufacture? As an aside I have a similar problem with a Samyang 85mm lens but I have no doubt about the cause of the problem - it became detached from a Geoptik EoS mount one night and bounced its way around the stone paved patio I wonder if/fear your lens may be out of alignment as is my 85mm lens.
  7. A clear night and an opportunity not to be missed. I've fitted the ASI1600 back onto the Samyang 135 with my Antlia 3nm filters - lens shut down to f3.0 with a step-down-ring - not sure whether that is totally necessary but f3 is still pretty quick. Centred on Zeta Cephei: ... 15 x 300s of S, H and O. Adrian
  8. So would I - everything is working just fine so it is best left alone and not worried about; I am confident I am feeding everything with 12.5 volts irrespective of what to ASIair says. This thread is actually about helping @Ouroboros with his ASIair Plus problem.
  9. No idea - you tell me! The output from my MeanWell p.s.u. is set at 12.5 volts (more or less confirmed with an inline power analyser which shows 12.43 volts). All I know is that it works.
  10. Not noticed any stickiness with my power switches - other than when I am having finger trouble. Here are my power settings: I tried swapping items around and all Outputs record the voltage; for some reason dew heaters don't record the voltage. HTH
  11. Exactly my concern - I've invested significantly in 1.25" filters
  12. It's a difficult balancing act between removing green cast and not reducing green too much such that it throws off the RGB histogram balance. This is your original with histogram... ... and after applying SCNR .... The peaks are now slightly better aligned and the relative differences have been reduced and the balance has been improved. Tricky things flats! I've had lots of fun and games (Not!) taking flats that do the job properly and actually produce a flat image. I was trying to reduce this - which I suspect is jpg artefacts rather than anything else:
  13. Ah, the captivating Bubble - it's a real challenge! This is all down to personal taste but this is what I achieved: Looking at your image there appears to be some back ground gradient - like vignetting - which is not helping to achieve a flat background. I applied ABE to try to flatten it best I can and then super-stretched the mask so you can see the problem. I used SCNR 90% to reduce the green cast. I also inverted the image and used SCNR 100% to remove the magenta. I used an L mask to reduce the noise (and I am bound to have lost some detail as this is a jpg) and I also carried out a tiny bit of sharpening to try to ameliorate the noise reduction. I created a second L mask and boosted the gold and the blue a little. Colours are all down to personal taste and I am not a fan of green or magenta but quite understand some members like to retain the green Hubble'esque look. I hope this is of interest.
  14. It can be tempting to use a large Coarse step size but I would be cautious and start 'small' and increase gradually to ensure you get sufficient change in HFD for the process to work and generate the 'U' curve. As I said it all comes down to your particular gear ratio. My belt system is approximately 20:1 - I think. With my Fine step of 13 I can barely see the focus ring move - with the Coarse step of 26 I can clearly see a small movement. If you set 'Reverse' the routine should (hopefully) initially drive the focuser away from the 'infinity' point - toward '10' or '5', and then step back gradually to go through the minimum point. Good luck.
  15. Sorry to hear you are having problems. Frustrating! Have you tried setting the Reverse option? I measured the Backlash on my system accurately and chose my Fine and Coarse based on the backlash figure; as I understand it the Backlash is not used in the Autofocus routine. As you have a different gearing arrangement I assume you need to use different Fine and Coarse figures. Fingers crossed this helps.
  16. Sounds like a good plan! You have been very thorough in your investigations and preparation. In my case I base the focus position for my lens purely on the result from using the Canon 6D, which when focused at infinity (or for sharp stars and perfect BM pattern) is right in the middle of the base of the 'L' - what is good for the 6D will be good for my ASI camera - or that was my thinking. I have now switched my ASI183MM for my ASI1600MM - (I still get one dodgy corner so it is not the sensor!) - and I am going to try using my ASI183MM with my f1.4 Samyang 85mm manual lens. As it turns out the f.o.v. for the SY1600 combination is almost identical to the SY85 combination - what luck! I've ordered the M48 adapter so once that arrives I shall have all sorts of fun trying to establish the correct spacing all over again - joy! Clear skies and thanks for the interesting write-up - and photos! Adrian
  17. I have an 11" iPad Pro 64 gb which apparently has 8 gb of RAM - ASIair Sky Atlas runs without problems. I have a 128gb iPhone 11 which apparently has 4gb of RAM - ASIair Sky Atlas runs without problems. I also have a 'cast-me-down' 7" iPad mini 32 gb which apparently has 4 gb of RAM - ASIair Sky Atlas won't run at all! Make of that what you will. Maybe the old iPad mini uses its internal RAM differently to the newer 11" iPhone 11. HTH with your deliberations.
  18. Good to see you back Brendan. I really like the way you've processed the dark stuff and the sense of depth you've achieved across the whole image - I particularly like the bottom centre to right corner - it just draws you in. Adrian
  19. This was a single 300s Ha frame from last night to check image train alignment - I am pretty pleased with this: ... and the result of stacking 10 frames in APP: .. all cut short by the early arrival of clouds! Adrian
  20. This is very frustrating for you - it can be a very frustrating lens to set up and I can only hope your lens is not defective. To illustrate the point I decided to swap my ASI183MM for my ASI1600MM on the Samyang last night. I made the not unreasonable assumption that the sensor position would be the same on both lenses so I just took the 183 off and screwed the 1600 on to the EFW. My preview image was very out of focus - blobby stars! I found I could not achieve focus at all - I was getting close but the lens was up against the end-stop. I decided to remove the 0.5mm spacer between the EFW and the camera (used purely to get the orientation of the sensor so it was orthogonal to the Vixen bar - in 'landscape'). Removing the 0.5mm spacer allowed me to achieve focus but with the focus mark approx 3mm before the 'L'. After much messing around in the dark at midnight I finally achieved focus with 0.3mm of spacing - the lens focussed on L, Ha, OIII and SII all within the confines of the 'L'. I can but assume the sensor position on the 183 is different to the 1600, i.e. the back-focus is not 6.5mm - I assume it 6.7mm. I read somewhere that ZWO state the sensor is positioned to with ±0.5mm - that is a lot when used with the Samyang 135mm (and have seen the same quoted on CN). I suppose the back-focus could be anywhere between 6.00 and 7.00 mm - again a huge range when trying to set up the Samyang. I can only suggest to persevere but bear in mind the 44mm figure is purely a starting point that will be affected by filter thickness and sensor position. The gap between my ASI1600MM camera front face and lens end plate is 38.73mm, so the spacing is (38.73+6.5) = 45.23 (±0.5mm cos' I don't really know where the sensor is!). Finding the right spacing for your setup is based purely on trial and error and a range of 1mm for the sensor position is a real challenge for the Samyang. (I also read somewhere that 'top-end' dslr manufacturers place the sensor to within ±0.01mm of the flange plate interface with the lens). Sorry I cannot be of more help. Good luck! Adrian
  21. I do like it! Personally I prefer the colours to be less vibrant but that said the structure and detail is very revealing - especially this bit: Never mind "the fingers of God" ..... spooky! Adrian
  22. I'll PM you later rather than add to this thread
  23. Hi Carole SCNR is Subtractive Chromatic Noise Reduction (SCNR) - it is designed to perform noise reduction and in particular to remove colour casts. There's still plenty of green left in the image as per the histogram: Without SCNR (and inverted SCNR) the histogram for the image is ... ... so it is pretty clear what SCNR has done - the main body of the histogram is largely unchanged. I should have been more careful with my choice of words and said use SCNR "to remove the green (and magenta) colour cast". Adrian
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