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Question about light gathering


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Is there a difference between between the image of a handheld binocular and a binocular mounted on a tripod? Apart from the steadiness of the image of course. Does a steady binocular gather more light than an unstable? If I say, look at the location of a dso with a tripod, will I then be able to see objects, which I otherwise would not be able to see if I did not use a tripod? And if, does this apply to telescopes as well?

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No matter how steady or unsteady, the light gathering ability for a wave form for the size of aperture should a be constant. I do not think it diminishes because you have a case of the jelly wobbles.

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No matter how steady or unsteady, the light gathering ability for a wave form for the size of aperture should a be constant. I do not think it diminishes because you have a case of the jelly wobbles.

True, but if the instrument is supported firmly you can see fainter objects because your eye/brain gets more of a chance to "integrate" the image ... I'd say the difference might be as much as 1.5 to 2 magnitudes between a hand-held 10x50 binocular and the same instrument mounted firmly.

Steadying the instrument by supporting it on the top of a fence etc. also works & gives nearly the same improvement as a tripod. Where a tripod really scores is that you can "park" the instrument whilst consulting charts etc. without having to find the target object again.

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Very true there is a big difference between hand held and mount fixed, but the light gathering ability for the size of objective should remain as a constant, the gist of Mettyman`s question : Does a steady binocular gather more light than an unstable one ?, optically I believe the answer to be no, does it give better views if mount fixed?, the answer to that is an emphatic yes. If your objective is steady and fixed on a light source the light gathering ability of the lens will work to its maximum, if its dithering about by hand holding, the light gathering properties do not IMHO reduce in any way.

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The physics of the optics says no difference but the neurology says that the eye needs to have a stable relationship with the optics. Even sitting down at the eyepiece of a well mounted telescope makes a big difference to what you see. Try it!

Olly

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I just thought there might be a difference since astronomers are able to capture images extremely far away with the hubble telescope by doing long time exposures on black patches of the sky and then receive the most beautiful images. Thought it worked the same in real time as well. :D

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I just thought there might be a difference since astronomers are able to capture images extremely far away with the hubble telescope by doing long time exposures on black patches of the sky and then receive the most beautiful images. Thought it worked the same in real time as well. :D

That's as maybe, but the light captured on long exposures is "stored" to make an image, the light coming into your bins is "lost" immediately

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