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6x telescope or 4x telescope
#1
This may be the ultimate stupid question, but i want to get beyond guesses.
My 55-200 mm Nikkor lens works like an 82-300 mm (in 35 mm terms) becauise of the 1.5 sensor correction. In 35 mm terms (where 50 mm is normal), it should look like 6x telescope through the viewfinder. Now when I look through the vuiewfinder of my SLR am I seeing a 6x telescope (30 mm) through the lens or a 4x telescope (200 mm). Do they used masks on the viewfinder or what?
Nikon D3100 with Tokina 28-70mm f3.5, (I like to use a Vivitar .43x aux on the 28-70mm Tokina), Nikkor 10.5 mm fisheye, Quanteray 70-300mm f4.5, ProOptic 500 mm f6.3 mirror lens. http://donschaefferphoto.blogspot.com/
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#2
It depends on the telescope's starting and finishing magnification.
In terms of magnification they will be the same (4 x approx)
Nikkor (55-200) or 82.5 - 300 is still only 3.6363636 times magnification, Because you multiply both ends by 1.5.

(If your telescope has 4 times magnification, and the large end was 100mm, the small end would be 25mm)


The viewfinder is just a glorified square, set to give you the view that the sensor gets from the lens.
If you have an full size sensor camera, then the viewfinder would be set to give you the view that that sensor gets.
Lumix LX5.
Canon 350 D.+ 18-55 Kit lens + Tamron 70-300 macro. + Canon 50mm f1.8 + Manfrotto tripod, in bag.
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#3
Gotcha. That's what I thought.
Nikon D3100 with Tokina 28-70mm f3.5, (I like to use a Vivitar .43x aux on the 28-70mm Tokina), Nikkor 10.5 mm fisheye, Quanteray 70-300mm f4.5, ProOptic 500 mm f6.3 mirror lens. http://donschaefferphoto.blogspot.com/
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#4
Well it is not quite accurate but will suffice I think.
A telescope (the big ones anyway) have separate eyepieces that alter the effective magnification or something like that.Rolleyes
Lumix LX5.
Canon 350 D.+ 18-55 Kit lens + Tamron 70-300 macro. + Canon 50mm f1.8 + Manfrotto tripod, in bag.
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#5
Yes they are just magnifying glasses to magnify the image.
Nikon D3100 with Tokina 28-70mm f3.5, (I like to use a Vivitar .43x aux on the 28-70mm Tokina), Nikkor 10.5 mm fisheye, Quanteray 70-300mm f4.5, ProOptic 500 mm f6.3 mirror lens. http://donschaefferphoto.blogspot.com/
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