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Steenamaroo

Is there more to be had? (moon - sharpness - 200p - 500d)

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Hi all,
I've been dabbling for about a year and am having a lot of fun.
Nothing too serious and I don't have mega expectations but I'm starting to wonder if my images could be sharper and there's something I'm missing.

 

I'm attaching a picture which is the best 10% of a 3 minute video with 500d 'bolted' straight to the 200p f5 scope. No filters...no barlows...just camera straight on.

It's sharpened and saturated after the fact so in every way this is the sharpest I can get it.

I've always had the same issue whether it's with a single shot, stacks of shots, or stacked video.
Views through the eyepieces (circle-T 12.5/25) are mega sharp!

 

I'm happy that collimation is very good and it was a remarkably clear night tonight.
All in all I'd be pretty happy with this image (maybe over exposed a bit...) if the craters with shadows didn't make me want to rub my eyes.

 

Thanks in advance for any thoughts or advice!

Moon10%2.png

Edited by Steenamaroo
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Have you considered trying some smartphone photography?

Single smartphone shot with my 80mm APO and a Baader Neodymium filter.

22C93B2D-BCFB-4D86-A34B-AB0853500C29.png

Edited by johninderby
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I could give it a go, sure, but why would that be sharper than a 500d?
It clearly is, but I don't understand why.

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2 minutes ago, johninderby said:

Have you considered trying some smartphone photography?

Single smartphone shot with my 80mm APO.

22C93B2D-BCFB-4D86-A34B-AB0853500C29.png

I agree with John.

I'm no imager at all but I've been happily surprised what even my basic android phone can do held over the eyepiece. I've bought a very cheap phone holder which makes this a little easier. Here are a few of my mobile phone shots which are nothing special compared to what the specialist imagers can produce but they made me happy :smiley:

 

rupesrecta.jpg

luneclipse160719.jpg

venus200520.jpg

merctrans111119.jpg

sol180419detail.jpg

20190513_204722.jpg

20190609_215717.jpg

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Smartphone cameras can be surprisingly good for simple AP. 👍🏻

I’ve been experimenting with an inexpensive microscope camera that shows promise although have just gotten the proper adaptor so should be able to get better images.

C657F738-A9C7-40BC-9E44-935C811B6EE0.png

Edited by johninderby
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I think that DSLRs can suffer from shutter slap causing vibrations and soft images. I've always found that I got better lunar images using a phone taking pics through the eyepice than using DSLR attached directly to scope.

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For sharpest images with DSLR you are better off taking single frames rather than video: I note that 500D has  a 15MP sensor and records up to full HD 1080p which is only 2MP. This means that the video is resampled and of much lower resolution than the camera is capable of. Additionally the codec applies compression to the video (probably IPB, interframe compression) which is very lossy. So using the video frames you don't get the full benefit of the sensor.

You can try taking 100 single shots in raw format  and stacking them to see if there is an improvement.

 

Nikolay

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With a DSLR taking images of the Moon, the exposure times that are usable generally give you problems from shutter shake and mirror slap. With my Nikon D750, I lock the mirror up and use a remote wire-less release to minimise this. Also, using a very heavy mount instead of a photo tripod will reduce vibration if you use a small scope. For example, using an ED80 (the original full resolution image is very sharp).. Don't forget, if you use a phone at the eyepiece, you are adding two extra optical components (eyepiece and phone camera lens) which can introduce distortion.

Chris

 

moonsmall.jpg

Edited by chiltonstar
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Thanks for all the suggestions, folks

I am using a good heavy mount with decent tracking and remote shutter so that's a few things ruled out, at least.
I appreciate the resolution for video is going to be much lower than for an image but figured I should definitely at least try a decent video, stacked, for comparison, before asking for advice.

 

I'll take some time to compare multiple DSLR raws, picking the best, with iphone/eyepiece shots and see what I can come up with.

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