Do I need a D800E if I have an M9 and Leica lenses? I am confused.

[theguywitha645d]

What would the correct viewing distance/print size be for a 180 degree fish-eye image? I imagine that if it is rendered flat (as most prints are), you should print infinately large (or squeeze your noise into its center)?

-h

This is were things are tricky. The fish eye is not the same projection as a rectilinear lens--the lens projection need to be taken into account to eliminate the perceived distortion and in this case no flat print would work. You would need to print a fish-eye image on a spherical surface. With a swing lens panoramic camera, you would need to print on a cylindrical surface.

But if you are choosing the lens for its effect, you would want to print on a flat surface and view from a distance.

[BJL]

What would the correct viewing distance/print size be for a 180 degree fish-eye image?

Correct viewing then requires the correct eyes: you must be a fish.

[Ellis Vener]

"Do I need a D800E if I have an M9 and Leica lenses?"

Because there is a far larger variety of lenses from fisheye to ultra-telephoto, including zoom, shift/tilt and macro lenses , available for an SLR camera design as opposed to a rangefinder camera. Likewise sometimes a small, quiet and precese camera and lens combination  is the better choice of tools.

Now if you'd asked "Do I need a NEX-7 if I have an M9 and Leica lenses?" The choice becomes far more intriguing.

[DeeJay]

Sized down to Leica M9 of 18mp I'm actually going to stick my neck and and guess that the Leica is still going to have better image quality due to the lenses. I am looking forward to seeing comparisons between the Leica M9 and 800e and also comparisons where Leica is upscaled to the Nikons pixel count where I've had really good results from.

[Ray]

Correct viewing then requires the correct eyes: you must be a fish.

Another question which I find quite intriguing. What is the 'correct' viewing distance for a 24"x30" photograph of a galaxy, or cluster of stars, taken by the Hubble Space Telescope, when such galaxy is, for example, 10 billion light years away.

Any possibility of correcting for the illusory perspective? 

[BJL]

What is the 'correct' viewing distance for a 24"x30" photograph of a galaxy, or cluster of stars, taken by the Hubble Space Telescope, when such galaxy is, for example, 10 billion light years away.

That's easy: far, far away from the print, so that the image appears as small as the galaxy does to the naked eye. Yes, this idea of "correct" viewing distance in the sense of same apparent (angular) image size as the photographer say, or WYSIWTPS ("What You See is What The Photographer Saw", but only if he was looking over the camera, not through the viewfinder) is very ill-fitted to the viewing of telephoto or macro photography. It might have some relevance to viewing normal to moderately wide-angle images.

Another case of the dangers of being rigorously PC (Photographically Correct).