Clavius Moretus 6/8/06

[sheeny]

This a mosaic assembled from two stacks of images.

Capture:
Negative projection, C8, 2.5x Powermate, moon filtr, ToUcam.
K3ccdtools, >1200frames, 10fps, brightness 50-75%, gamma 0-30%, saturation 0%, gain 20%, 1/25 sec, seeing poor.

Processing:
Registax: 100 frames.
Photoshop CS2: adjust levels (to match), photomerge, crop, unsharp mask, save for web.

Resolution: approx. 400m per pixel.

Al.

[RAJAH235]

WOW!.. Brilliant pic.... Couldn't you get any closer?.....:P..:D L.

[iceman]

Just beautiful Al. Great detail and resolution, especially given the seeing.
Top stuff!

[hevelsky]

Fantastic image Al. :thumbsup: amazing resolution :eyepop:
Great Job !!!

[2020BC]

Wow.

[Robert_T]

This is truly excellent - how on earth (or on the moon:P ) did you pull that from poor seeing??? By the way, what's "Negative projection"? Is that just sticking a toucam into a powermate with no eyepiece?

cheers,

[sheeny]

Thanks Guys.

How with poor seeing?... I was lucky in some ways...
1. I took relatively long avis (high frame count)
2. I tried to keep exposure time short (<1/25 sec)
3. I took the time to do a short for drift alignment (drift aligned in azimuth only on Jupiter prior to starting to image - both Jupiter and the moon were high in the sky and I knew my lat adjustment should be close enough)
4. I used lunar tracking rate. Steps 3 and 4 allowed me to capture the long avis...
5. I was really, really careful with focussing. When I got the occasional sharp frame flashing up through the seeing, I was happy... leave it at that.
6. Compromise the number of frames stacked for quality of the images stacked. Fortunately, because I was able to take long avis, this compromise was minimal.
7. Play with different wavelet sets to see what works for the image. Not every image is the same. I tend to try the higher order wavelets first since they work more locally. If the image is sharp enough to only need high order wavelets to crispen it, then using lower order wavelets only introduces artifacts. But be prepared to experiment with wavelets.
8. Have patience.
9. Practice often (as if I do that!:rofl: ).

Robert, you are absolutely correct about negative projection.

Al.

[sheeny]

PS. When capturing these avis, I was able to get just the odd frame snapping up sharp. I haven't often achieved that in the past in poor seeing, probably because I try too hard to focus to get more of the frames sharp... it doesn't work. You end up frustrated and setting for a poorer focus anyway IMHO.

When you look at the quality curve in Registax for these AVIs there is a steep drop in quality on the left hand side. I think the quality limit I was using on these avis typically between 83% and 93% for the best 5% of frames. Normally I would be aiming for 95% or higher for the best 25% of frames with a curve that was very flat from the start - indicating most of the frames are very unitform in quality (probably unitformly out of focus!:rolleyes: )

So it was a bit of an unusual session for me... I got success from it, I'd like to think I've learned from it, and hopefully I can repeat it!

Al.

[Robert_T]

Thanks for the detail Al, Makes sense - in poor seeing less is more:D

[ving]

that is one stunner of a shot!
almost like being there hey! :D

[sheeny]

I've just reworked this mosaic again with another stack above Clavius. Shame I didn't get the little bit of the limb in between!:doh:

Original unwaveletted images out of registax were photomerged in PS CS2, wavelets applied in Registax, then cropped and saved for the web in PS CS2.

Al.

[iceman]

Very nice Al! A shame about that missing piece of the puzzle, would make for a spectacular image. I've done that a few times myself, and it's very frustrating!

[[1ponders]]

ripper shot Al. :thumbsup: Great planning helps to take a great image.