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About Tommohawk

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  1. Brilliant that's helpful to know. Do you know is that just a transient feature?
  2. Thanks! My colour vision isn't so good, so if it's even close I'm happy. Thank you... Hoping for further improvement s with tonight's effort.
  3. Still experimenting with my set up and making some progress I think. Last night I think I proved that always trying to go for the shortest exposure possible in order to freeze the seeing isn't necessarily helpful. I did 5 x 3 min AVIS with 1.5ms and one with 3.5ms - the latter was definitely better. Wish I had more now, or maybe tried even slower. Maybe another go tonight.... it looks clear again. One other thing I discovered is that my colour balance is off when capturing such that processing requires quite a tweak. PIPP aligns the RGB histo so sort this, but presumably better done at the time of capture - I'll experiment with white balance. I also only set WP to 65% rather than my usual 75% to try and stop the ice cap overexposing. I think it helped. As noted in this post, the lower right limb seems cloudy - not sure what that's about? 250mm F4 with 5x powermate (though only set at approx x4) and Omegon 385C, captured with Toupsky, PIPP, AS!2, PS. Next effort will have more data so hopefully better!
  4. OK thanks for that Craig. I hadn't appreciated the ADC has that issue - glad I kept my money in my pocket!! (But of course I can see the benefit with lower targets.)
  5. Sounds good Geof. I wasn't aware of the cut out option in FC - but how is this different from just a smaller ROI if you're only writing the central 400x400 area? As it happens the Omegon 385 wont run on FC, so I've had to learn Toupsky. It works well, although some aspects not as slick as FC.
  6. Thanks Geof. I'm just playing around with last nights Mars data and one obvious disadvantage of using very short exposures is that you end up with massive files. I have 126GB I'm trying to manage by decanting it over to an external drive. It's slow and painful! In the past I've always aimed for as short an exposure as possible for best "freeze the seeing" effect and assumed the noise resolves by virtue of having more frames - but I'm assured by others who know better that this isnt the best approach. Yesterday I did 5 x 3 minute videos or Mars with a modest 35/50 gain and 1.5ms, but I also did one 3min video with 3.5ms - and this definitely looks better. So this seem to prove the point. I will experiment again and try and find the optimum. PS at the moment I'm testing an Omegon 385, rather than using my ASI290, so this may have a different optimum exposure.
  7. Lovely image! Pretty sure that would benefit from some sharpening/wavelets too. When you say ... ...do you mean top left as we look at it? I'm just processing my effort from last night and have exactly the same thing, although mine is less because shot about an hour earlier by the look of it.
  8. That's a super Mars image Geof... and thanks for sharing the workflow and thinking process. Re the ADC would be interested to know why they are thought to be unhelpful with higher altitudes. Obviously less dispersion at higher altitudes so not such an issue but if its 2 prisms that's 4 surfaces and I guess each one loses some signal and creates some reflections so that may be it. Also interesting that you go for a relatively lower frame rate and keep more frames than I normally do. Quality rather than quantity! I'm sure he's right...... but not clear quite what he means by this? I also have an F4 newtonian scope (without CC) so take care to ensure the image is central. But I use the RA DEC controls to re-centre... not sure why thats an issue, and what does he mean by using "collimation controls"? Ohhh wait... does he mean the ADC causes an offset?? In that case recentring with RA DEC would effectively mis-centre the image. think I've answered my own question!
  9. Lovely Mars image, nice fine details.
  10. I just thought I'd post my best effort with my Canon 550D DSLR to show what can be achieved - IF you can use uncompressed video. This was done with a Skywatcher 200PD, so a budget scope, with a 5x powermate, 550D using video crop mode It's clearly not to the same standard as a dedicated planetary camera but it's fair I would say. I looked at Magic Lantern software - which apparently can be downloaded to your camera (I've never tried this) - but I dont this it will help. It appears that the 6D just wont do uncompressed or RAW movies at all - unless someone knows better?
  11. In your image editor there should be a way to crop the image. You mentioned Lightroom - see this help page I agree.... a powermate, whilst excellent, isn't your priority. You need to sort your image capture first - find a way of doing uncompressed video, stack multiple stills, or bite the bullet and go for a planetary camera.
  12. Just as a BTW there's a calculator for magnification with eyepiece projection here. You can then check how differrent a Barlow/Powermate might be
  13. I'm not sure if I understand you correctly, but to a great extent this is about how you display the image. You can certainly make the image appear bigger by cropping it and resizing it. Of course this is likely to lose resolution because you have to interpolate for the additional pixels. You really need to increase the raw image size by a combination of image amplification and ideally small pixels. My current planetary camera has 3.8 micron pixels so not teeny weeny, and I use a 5x powermate. I would bite your arm off for a go at planetary imaging with that scope!! You are right that you have to be careful with trailing cables especially because the camera position would move around considerably with a big newtonian, but for planetary work aperture is definitely helpful. The best images posted here are typically done with big aperture scope like 14" SCTs or big newtonians. Yes, you need quite a lot of RAM and importantly USB3. Also quite a decent sized hard drive - some nights I get through 100+GB. My current laptop I bought used for £250 - it has 500Gb, 8Gb RAM and USB3.
  14. I'm not seeing much differences between any of these! But not on home screen at the moment. One query. When you join 5x2 min vids, do you then use same percentage of total frames for the stack? I meant to add though that having read about issues with WinJupos, and AS2 ability to deal with it to some degree, I've stopped doing derotation
  15. Thanks Dave. My previous efforts at Mars have been pretty dismal, not sure what's different this time. Good luck when you have a go!
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