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mrklaw
8th of October 2008 (Wed), 16:13
Hi

took some shots of the moon today, but they're not hugely sharp. Looking at it 10x through liveview, there was noticable 'haze'. The moon was quite low to the ground and its been a warm day here in the UK for a change.

Is there any way to process multiple images to avoid some of the distortion this haze may have caused? I took 8 identical images just in case...

Nighthound
8th of October 2008 (Wed), 17:08
If it's your goal to remove the haze or glow around the Moon, you could try adjusting curves in PS, may need to create a mask. The distortion is a whole other matter. Very low altitude Lunar shots are most often eaten up by the dense atmosphere. The distortion is near impossible to correct, especially if taken at high focal length. Unfortunately stacking won't remedy what you've described, although there's certainly no harm in trying. Post a shot so we can see what you're starting with.

I spent all night last Saturday(night fall to dawn) shooting deep sky and come to find out that I was a hair out of focus on all my exposures. I knew it would be less than I wanted but I went ahead and stacked some anyway. Not the results I was after - poor data in, poor data out. A night wasted but not completely, it was still fun and I learned a lesson, again. :)

mrklaw
8th of October 2008 (Wed), 17:43
I'll post something up in a bit. Its surprising just how critical focus can be. I'd have thought that with something so far away, you'd be able to just whack the focus ring right the way over to infinity and you'd be good to go. but at long focal lengths its difficult. even with liveview you're still touching the camera so you get lots of wobble.

heh. According to Dofmaster, at f11/600mm, and focusing at a subject 500,000km away, everything from 1.6km to infinity should be in focus :D yet why then does the moon blur so easily when manually focusing?

mrklaw
8th of October 2008 (Wed), 18:08
here you go. Just seems soft generally - click through to the larger sizes. the others weren't much better. The moon was very low in the sky though - will I get much better results if I wait until its higher up?

http://farm4.static.flickr.com/3191/2924717535_65fa176c8d.jpg (http://www.flickr.com/photos/23947576@N05/2924717535/)

Johnny9s
9th of October 2008 (Thu), 02:12
Have you run the shot through photoshop or anything? You can sharpen the image up quite a bit with the tools in most image editing software.

Make sure you are using mirror lockup and a remote or timer as well.

John

mrklaw
9th of October 2008 (Thu), 08:51
did use MLU and remote release and tripod. I had sharper results with the 100-400 and 2x teleconverter so thats why I was thinking the atmosphere may have had an effect. It was a clear night though.

Its already a little sharpened in elements.

Its also ISO 800 as it was really dark with anything much lower - or needed a low shutter speed. at f11 and ISO 100 it was needing 1/15 shutter speeds to stop it looking very dark on the review image. that confused me too.

Nighthound
9th of October 2008 (Thu), 10:22
A clear night does not necessarily mean a steady night. Turbulence in the atmosphere is a major factor in Lunar imaging when striving for sharpness/clarity. My highest quality Lunar shots were almost always taken in the hours just before dawn. During the hours after sunset the Earth is going through its most intense cooling period. Radiational cooling whether from the Earth or the rooftops in your neighborhood will cause distortion.

Your exposure looks very close to right on. Softness could be due to optics, focus and/or the atmosphere. Bracket your exposures over and under what appears right on your LCD. This will insure the correct exposure. You might look into something like the Canon Anglefinder C for viewfinder magnification. There are some out there that are much more affordable than the Canon model. I have the Canon and it does help with focus when shooting Lunar.

Try finding a way to make your tripod more stable. Suspending a weight from the center stem downward can help. And of course avoid shooting out in the open if there's a breeze. You've got a very nice shot here and with practice you'll have this down in no time at all.

bromm
11th of October 2008 (Sat), 20:05
did use MLU and remote release and tripod. I had sharper results with the 100-400 and 2x teleconverter so thats why I was thinking the atmosphere may have had an effect. It was a clear night though.

Its already a little sharpened in elements.

Its also ISO 800 as it was really dark with anything much lower - or needed a low shutter speed. at f11 and ISO 100 it was needing 1/15 shutter speeds to stop it looking very dark on the review image. that confused me too.

I use the 400mmL and I generally shoot the moon when it is higher in the sky, iso 100-200 and shutter speed 1/200th- 1/350th depending on the fullness of the moon. Aper of f/8.

I shot some tonight for the first time with the 40d, tried the live view at 5X for focus. Will post results later, it was quite cold out there tonight so the gear is acclimating in the gear bag.

Adrena1in
3rd of November 2008 (Mon), 06:37
...it was needing 1/15 shutter speeds to stop it looking very dark on the review image. that confused me too.

When I shoot the moon and use Live View to focus it, I always have to set the exposure time quite long to get the Live View image bright enough, but that doesn't mean that's how long an exposure it really needs. For anything over a half-moon I won't shoot at shutter speeds slower than at least 1/250th. But when set to that, the moon is, as you say, too dark on the Live View. Just a "feature" of the camera I guess.

I guess the Live View is incapable of showing accurate images at longer exposures. Take star shots...I can only ever see particularly bright stars on Live View, even when I'm set to 30s or Bulb, but take such a long exposure and thousands of stars will appear on the image.

Jeff
3rd of November 2008 (Mon), 09:01
Take star shots...I can only ever see particularly bright stars on Live View, even when I'm set to 30s or Bulb, but take such a long exposure and thousands of stars will appear on the image.

When you're doing this is it through a lens or a larger aperture telescope?

Adrena1in
3rd of November 2008 (Mon), 11:12
When you're doing this is it through a lens or a larger aperture telescope?
Either...I think...? On holiday last week I was using my 50mm and then 10-22mm, and on both I needed to locate a bright star first for the focus. The other night I was trying to shoot part of M45 with my 1200mm, and it was the same situation.