Eagle Pillars and HiRes cores of Triffid, Lagoon and Swan nebs.
SPX350 F9.1, ASI290 Binx2 0.38"/pixel, Baader RGB, Astronomik UHC.
I spent May to Aug imaging these waiting for the best seeing which I managed to find eventually for these nebulas. Exposures are from 2-3 secs with no calibration.
I have comparisons of detail with HST. HST images had to be reduced drastically to match my puny focal length, but it is just for fun.
Great to see, nice images John! I'm convinced such lucky imaging will become more popular and successful. I have loaned out my asi224 to a friend but once I get her back and the adapter I need arrives, I'll be doing some LI myself.
Can you tell us the exposure details, e.g. number of subs and gain?
That is amazing resolution John. This new lucky seeing imaging approach really is paying dividends.
Greg.
Yes Greg, the pillars I spent the most time on with over 5200 2.5sec exposures in good seeing. Registax would include plenty of poor images amongst the best so I went through it by hand stacking nearly 2500 sharp subs, it took several hours - very boring.
Quote:
Originally Posted by Atmos
Incredible resolution John!
I’ve managed close to your Pillars but it’s that final hard contrast and resolution that has escaped me.
Resolution is really down to seeing, I spent many nights and threw away hours of images once better seeing came along which it eventually did.
In PShop I use Image-Adjustments-Shadow/Highlights which really lifts the dark detail more than the bright detail and there is a contrast slider, if your image is not too noisy it gives good results using layer opacity slider to suit. ASI cameras do have low noise.
Quote:
Originally Posted by SimmoW
Great to see, nice images John! I'm convinced such lucky imaging will become more popular and successful. I have loaned out my asi224 to a friend but once I get her back and the adapter I need arrives, I'll be doing some LI myself.
Can you tell us the exposure details, e.g. number of subs and gain?
Yes the exposures may vary from 2.5 to 3 secs gain full depending on the breeze except for M8 which is much brighter at 1 sec exposure. With Triffid bright stars I used a half sec exposure and a 100 each RGB.
Astonishing sharpness-resolution-detail. Just breathtaking. And beautiful, too.
Does your camera have an electronic shutter? We'd wear ours out doing that. How long does an image take to download? The 0.34" arc resolution - is that at 1x1, meaning 0.67" arc binned, or is it actually 0.34" arc binned, meaning native 0.17" unbinned?
You mentioned waiting for the best seeing - we understand that means selecting the very best frames. Does it also mean only photographing near the meridian, or waiting for exceptional weather, poring over jet stream predictions, etc?
Did you use adaptive optics as well? If not, would it help?
What was the FWHM in the very best frames?
Unbelievable work. We're thinking of selling the scope and using our observatory to store farm chemicals.
Astonishing sharpness-resolution-detail. Just breathtaking. And beautiful, too.
Does your camera have an electronic shutter? We'd wear ours out doing that. How long does an image take to download? The 0.34" arc resolution - is that at 1x1, meaning 0.67" arc binned, or is it actually 0.34" arc binned, meaning native 0.17" unbinned?
You mentioned waiting for the best seeing - we understand that means selecting the very best frames. Does it also mean only photographing near the meridian, or waiting for exceptional weather, poring over jet stream predictions, etc?
Did you use adaptive optics as well? If not, would it help?
What was the FWHM in the very best frames?
Unbelievable work. We're thinking of selling the scope and using our observatory to store farm chemicals.
Very best,
Mike and Trish
Yes the ASI290 cmos has an electronic shutter and is really a planetary camera and can do several hundred images a second in an avi or ser file. I was trying it out on bright planetary nebs and the brighter emission nebs.
The scope is a 14" newtonian with 2xPowermate imaging at 3200mm. The image is 16bit binnedx2 at 0.38"/pixel or 0.19"/pixel with no binning, binning is way less noisy and suits the good seeing better. Full res needs the very best seeing to work. Cmos has 2.9micron pixels 1936x1048 pixels.
Seeing wa near 2" or 1.7" at best which for me is very good, objects were all inaged close to overhead moving way past often. I use CalSky seeing forecast.
Adaptive optics is only a guiding assist. I collect several thousand 2-3sec exposures and select them manually, choosing the only very sharpest before averaging, for the eagle 40% were used. If I had and Obsy that would be way better at cutting the airy breeze.
Regards, John.
Last edited by John Hothersall; 28-10-2018 at 07:37 PM.
A sweet Eagle there John. I compared it with mine from a few years ago and I have to say yours is larger and I think a little sharper than mine and I was really stoked with mine at the time. The detail on the Trifid jets is also nice too.
