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Old Jan 2, 2007, 8:29 PM   #1
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It has been suggested to me that the readily available refracting telescopes would make useful wildlife lenses at a most attractive price. One example is a f500 f1:5 telescope on a sturdy tripod for a bit over US$400.

I suspect there are pros and cons but just what are they? Obviously the aperture is fixed but I am wonderingwhat else would make a telescope unsuitable for this type of work?


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Old Jan 2, 2007, 9:05 PM   #2
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John Hill wrote:
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It has been suggested to me that the readily available refracting telescopes would make useful wildlife lenses at a most attractive price. One example is a f500 f1:5 telescope on a sturdy tripod for a bit over US$400.

I suspect there are pros and cons but just what are they? Obviously the aperture is fixed but I am wonderingwhat else would make a telescope unsuitable for this type of work?

John I don't know if this will help or not but I do a lot of digiscope photos (Using a spotting scope with a camera). About 95% or more of my photos are of free ranging wildlife. The reason I use the Digiscope is so I can get a close up after I have taken the back up photo. This allows me to get the close up without having to stalk as far.

If you go to my web site and type in close up or insert in the search you can see a lot of examples.

http://www.digiscopingdigest.com/

Here is what the equipment looks like.



TOTALLY WACKY roger
FZ 30, Nikon TCE17, QuikAim Max RDS, Zeiss Digiscope/Sony W7

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Old Jan 2, 2007, 11:37 PM   #3
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Roger, considering your spotting scope costs somewhere between $1,000 and $2,400 depending on what model it is, you can buy some fancy lenses for that kind of money.

John, I have found that real camera lenses do a much better job of getting quality images than spotting scopes or telescopes, no matter how good the scopes are. Scopes are also very slow aperture wise and seriously inconvenient to use with a DSLR.

They do work, but not the kind of quality I expect from my DSLR's.

Tom
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Old Jan 3, 2007, 12:00 AM   #4
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Thanks Roger, that looks like a very satisfying thing to be involved in.



Tom, I should sure hope those camera lens did provide something for the extra $$$!:-)

You say that 'scopes are slow aperture, but then so are the telephoto lenses I might be able to afford. However 1000m F5 must surely count as only moderately slow?

There must be some underlying reasons why telescopes are not used in photography.


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Old Jan 3, 2007, 12:28 AM   #5
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I have never seen a scope that was faster than f/8 when mounted on a camera and many of the less expensive ones are f/13 and up.

The quality of the images is far less than with a actual lens designed for the camera, especially at the edges, but then YMMV.

Tom
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Old Jan 3, 2007, 12:45 AM   #6
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Well Tom this is the one that was brought to my attention, http://www.nztelescopes.co.nz/skywatcher_102as.htm

Claims to be f500mm and aperture of 102mm, do these ratios not hold true when on a camera in primary focus mode?
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Old Jan 3, 2007, 1:02 AM   #7
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Well John, I can only tell you that I have used the Celestron C11-S (2800mm focal Length, f/10) which is a $3,000 telescope, for photography and it was disappointing to say the least.

It did get out there and record images from an amazing distance, but the quality of the images were not acceptable for my type of photography. It is not that they were bad, they simply were not good enough, or should I say sharp enough for me.

I would suggest you find someone that has one and try it before investing that kind of money, to see if it suites your needs.

Tom
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Old Jan 3, 2007, 1:47 AM   #8
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Hmmm, I know what you mean Tom, fortunately even the $700 New Zealand dollars (about $420 US) is enough to discourage me froma rash purchase. But it would be nice to know why a telescope performs poorly as a telephoto lens.

Besides, I would like to know just how poor they are, for example are they better or worse for example than a 600mm Sigma f8 mirror lens?
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Old Jan 3, 2007, 1:55 AM   #9
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My guess is no if you are using a high quality telescope. I have used a Pentax 500mm mirror f/8 and it was not up to my standards.
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