Is this in focus?

Using SharpCap for other Astro Imaging such as all sky cameras and meteor detection
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brenski
Posts: 82
Joined: Mon Aug 10, 2020 4:01 pm

Is this in focus?

#1

Post by brenski »

Would someone be kind enough to have a look and tell me if this allsky image is focused correctly?
is it sharp enough?

Zwo 178mc

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admin
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Re: Is this in focus?

#2

Post by admin »

Hi,

all sky cameras can be tricky to focus - if you are using a glass/plastic dome then the curvature means that it introduces some errors to the focus, so the image can look sharply in focus with the dome off and then be a bit blurry with the dome on. It may not be a case of 'is this in focus'?, but more 'is this the best focus I can achieve'?

cheers,

Robin
brenski
Posts: 82
Joined: Mon Aug 10, 2020 4:01 pm

Re: Is this in focus?

#3

Post by brenski »

thanks @robin

I have been trying to adjust focus with the dome off, however, as soon as it looks correct and I re-tighten the lens screw, the next capture looks "out". and that's BEFORE i reapply the dome!

i heard there was a trick to adjust focus more precisely, by first adjusting the actual lens collar from the camera, taping it down and then applying fine adjustment to the lens itself.

is there a quick and easy guide to how to do this?

thanks
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Re: Is this in focus?

#4

Post by admin »

Hi,

I don't have any tricks to share - I did mine by length trial and error :( Maybe other all sky users have some suggestions.

cheers,

Robin
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