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Attaching a DSLR to a Pentax Scope (1 Viewer)

HokkaidoStu

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Hope someone more knowledgeable about these matters can help me.

I recently got a new DSLR, a Canon EOS 400D, and very nice it is too. I'm using a fairly low powered 300mm lens whuch is ok but has its' limitations but I can't afford a longer one at the moment.

So I thought about attaching it to my Pentax 65mm Scope. I do some digiscoping with a compact already. My crappy kit lens has a 58mm thread which I guess in theory could be used to mate it with an eyepiece but the vignetting would (I guess) be brutal. Plus I'm not sure it would be able to support the weight of the camera anyway.......

Then there are these 2 options:

Universal T Adapter

Universal Projection Adapter

Both seem very economical solutions I have to say.

Am I right in thinking the first one is for prime focus and the second uses the Scope's eyepiece?

Which one would be more appropriate for a 65mm Scope? I gather the first option would be considerably less magnification. I did some searching on some of the threads in the Pentax forum but I'm sorry to say I got rather bogged down with some of the technical details.

Am I right in thinking F stops will be affected (ie much slower)? And what happens to metering and the suchlike?

I guess I'm just asking if it's worth going down this route with a small Scope.
 
stuprice68 said:
Hope someone more knowledgeable about these matters can help me.

I recently got a new DSLR, a Canon EOS 400D, and very nice it is too. I'm using a fairly low powered 300mm lens whuch is ok but has its' limitations but I can't afford a longer one at the moment.

So I thought about attaching it to my Pentax 65mm Scope. I do some digiscoping with a compact already. My crappy kit lens has a 58mm thread which I guess in theory could be used to mate it with an eyepiece but the vignetting would (I guess) be brutal. Plus I'm not sure it would be able to support the weight of the camera anyway.......

Then there are these 2 options:

Universal T Adapter

Universal Projection Adapter

Both seem very economical solutions I have to say.

Am I right in thinking the first one is for prime focus and the second uses the Scope's eyepiece?

Which one would be more appropriate for a 65mm Scope? I gather the first option would be considerably less magnification. I did some searching on some of the threads in the Pentax forum but I'm sorry to say I got rather bogged down with some of the technical details.

Am I right in thinking F stops will be affected (ie much slower)? And what happens to metering and the suchlike?

I guess I'm just asking if it's worth going down this route with a small Scope.

Either one could be used with or without an ep.

Be warned however that they only accept very narrow eps of not over 1.5 inchs or so and may or may not come to focus properly. Also with an ep there will be some loss of optical quality and slower.

Without an ep you will not get a correct image because of the built in prism on a spotter (left and right and up and down will be reversed).

As far as metering is concerned set your camera to aperture priority and manual focus and you will get through the lens autoexposure like any other lens.

SF
 
Sout Fork said:
Either one could be used with or without an ep.

Be warned however that they only accept very narrow eps of not over 1.5 inchs or so and may or may not come to focus properly. Also with an ep there will be some loss of optical quality and slower.

Without an ep you will not get a correct image because of the built in prism on a spotter (left and right and up and down will be reversed).

As far as metering is concerned set your camera to aperture priority and manual focus and you will get through the lens autoexposure like any other lens.

SF

Thanks for the reply.

It sounds like a non starter. If I understand it, this set-up may not work with an eyepiece and even if it does the quality won't be so good. Without an eyepiece the image will be upside down.............

Looks like I'm saving for that expensive lens then.
 
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