La Lune

[Astro_Bot]

My first moon, taken on 15 March 2014. Seeing was average.

It's a 6-panel mosaic stitched in Hugin. It doesn't quite have the resolution I was hoping for, mind you I was very gentle with the sharpening - hardly any at all - and only a touch of gamma and contrast to post process. A reprocess from the top down might be in order, if I get the time.

There's a large version (http://www.astrobin.com/full/84860/0/), if you're interested.

As always, any advice appreciated. :)

The attached version is small and compressed for upload ...

[nebulosity.]

Thats a really nice image :thumbsup:

Don't be afraid to do a bit more sharpening, and I would suggest reducing the exposure a bit to avoid the clipped highlights.

Cheers
Jo

[pw]

Looks pretty good to me.

[RB]

A wonderful image Mr Bot !
Love it.

:thumbsup:

[cometcatcher]

Looks good to me.

[CJ]

Very nice! What equipment and settings did you use?

[Astro_Bot]

Thanks for those comments. :)

I went by the camera's histogram to judge exposure settings - it wasn't clipped as far as I could see, but then that assumes I know how to use a histogram. IIRC, I used 1/200sec and ISO100 - that was at f/10.



Hi Chris,

I used a Meade LX200-ACF 10" and a Canon EOS 600d.

Each of the six panel images was 1:00 minute at 25fps of HD (1920x1080). The Canon EOS video is compressed with H.264 in the camera, so that might account for the upper limit of resolution. The videos were converted to RGB frames in VirtualDub then aligned and stacked in Registax - best 20% - then some very gentle wavelet sharpening and a little gamma/contrast in Cinepaint.

There was a little bit of wind about, and having just reviewed the original videos, there is a bit of vibration on top of the "wavy" moon.

If I reprocess ... hmmmmm ... I think I'll try far fewer frames to stack (5%?), be a little more aggresive with sharpening and play around a bit more with gamma, stretching etc.

[CJ]

Thanks for the tech info Astro.
:thumbsup:

[BruceG]

Spectacular!!!

[Dennis]

The smaller version looks nicely processed and very natural – great job.:)

When I opened the larger version, it looked as if a “soft focus” filter or smoothing had been applied to aggressively, or maybe too much JPG compression, as it has lost the crispness and detail of the smaller version?

Thanks for the DSLR capture and processing details, I have yet to use my DSLR for taking movies of the Moon.:thumbsup:

Cheers

Dennis

[Astro_Bot]

Thanks for the comment and feedback. :)

Funny you should mention focus, as I'm not entirely sure I had it spot on. I have a manual focuser on that OTA which is great for visual but lousy for AP and it's really quite hard to get it right. I had been using a Bahtinov mask but misplaced it (had to move stuff around for cleaning and now I can't find it!) so focus that night was achieved by eye using the small LiveView screen.

And, quite possibly, the OTA might have had something to do with it. The LX200 is corrected for coma, but not field curvature, so there can be a focus difference across the FOV. For most subjects, it wouldn't be noticeable, as the target is in the centre, but the moon is so darn big ....

Also, as mentioned, video compression in the 600d is at the low end of the quality spectrum (so I've been reading - allegedly quite lossy - though I don't know what the effect is for nearly-still images).

[Dennis]

I hear you regarding a corrected field.:)

My Tak Mewlon 180 (a Dall-Kirkham Cassegrain design) has a small, on-axis region of sharpest focus where it is very crisp but with an extended object such as the moon, as soon as I move away from that small, central sweet spot the sharpness degrades quite noticeably.

With my Canon DSLR, I can get around this by taking several shots for a mosaic, with the moon placed at different positions in the field of view then I assemble the sharpest region from each of the frames.

However, with the 3.54x2.69 mm ASI120MM chip I am always recording in that sweet spot in the centre.:)

Cheers

Dennis

[Astro_Bot]

Repro.

Large version here (http://www.astrobin.com/full/85340/0/).

I started at the top and re-stacked (Registax), re-stitched (Hugin), re-sharpened (Registax/Wavelets) and re-postprocessed (Cinepaint/GIMP).

I've come to a realisation, basically summed up by: So many processing options, so little time.

The final result was a hard one to choose from amongst the reprocessed versions I had before me, but I think this looks the best (although I could think differently tomorrow).

As always, I'm happy to receive advice. :)

[ourkind]

Wow who needs a terminator to see craters in this photo. Beautiful!

[Dennis]

Nice repro!

Cheers

Dennis

[Astro_Bot]

Thanks guys. I'll try and get the focus right next time. ;)