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The focus looks a bit soft. Try focusing on a star, then turn back to the moon.

There may be blurring due to scope vibration as you operate the shutter. Do you do it by hand, or have you a remote release for you shutter?.

Ron.

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You could try the Top Hat trick to eliminate any vibration.

Set the shutter to Bulb. Get the moon in view in your camera, and focused as you see it. Place a card over the front of the scope to block the light coming in. Open the shutter, and wait for about 10 seconds to allow any vibration to stop. The Try to guage 1/250th of a second remove the card from the tube front, and replace it in that short timespan. When doing this, be careful not to knock the tube with the card. Holding the card over the tube front, close the shutter again. A bit of practice will allow you to perfect this.

If it shows a big improvement in the resultant Image, then you need to adopt remote shutter operation.

Ron.

Edited by barkis
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The Try to guage 1/250th of a second remove the card from the tube front, and replace it in that short timespan.

Not an earthly ... the "top hat trick" really only works for exposures longer than 1/8 sec. I used to use this method 40 years ago when I had a camera that had only B and shutter speeds 1/30 sec & faster. I assure you that using the mirror lockup facility and/or the self timer on modern cameras is a hell of a lot easier as well as more convenient.

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Thanks guys i did forget to mention that I have used self timer as well of 10 seconds, but the image is still slightly blurred. With vibration i have seen more double images, whereas this could be focus.

i think my next effort will be using a laptop as a remote and trying to get a live view that way.

on a side note: does anybody know a place in London where astrophotographers meet up?

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Personally I don't think this problem is due to vibration, they just look out of focus.

However, you could try faster exposures without the barlow and see if the cropped images are better.

Maybe the light path to the viewfinder is not exactly the same as to the chip? Might be good enough for a short focal length camera lens but not a very long lens such as a telescope with a barlow.

So try a series of exposures at 1/250th, starting just visibly out of focus, and work through focus and out the other side. Make a note of the exposure number you think is in focus in the viewfinder. Then look at the images to see which one is in focus.

What size scope are you using?

(Focal length , aperture)

Good luck

Michael

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Personally I don't think this problem is due to vibration, they just look out of focus.

However, you could try faster exposures without the barlow and see if the cropped images are better.

Maybe the light path to the viewfinder is not exactly the same as to the chip? Might be good enough for a short focal length camera lens but not a very long lens such as a telescope with a barlow.

So try a series of exposures at 1/250th, starting just visibly out of focus, and work through focus and out the other side. Make a note of the exposure number you think is in focus in the viewfinder. Then look at the images to see which one is in focus.

What size scope are you using?

(Focal length , aperture)

Good luck

Michael

I do think that the viewfinder and sensor are a little out of sync. I need to read y camera manual on gettign live view activated as all my pics are taken based n viewfinder.

Because of my scope a t-adapter without the Barlow lens does not fully come into focus. I looked around and the only way to get focus with a SLR camera is by using the barlow.

I will try your idea next, or taking pictures at different exposures etc.

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