Here is a quick test I did comparing the 1Ds Mark II and the 1D Mark II using the Canon 15mm Fish Eye Lens. The idea was to see what the difference would be in the field of view between the full frame 1Ds and the 1.25 crop of the 1D. Both cameras were Mark II's. These shots are not meant to demonstrate sharpness or quality of either the lens or cameras. There are much better subjects/lighting conditions than what I had to work with today for that type of test.

I set up a tripod and leveled the ball head. Both cameras have the same mounting plate for the ball head. The tripod was not moved between shots. The settings were as follows:

Manual mode
f16
1/30 sec
RAW
Processed w/ ACR with same settings

The first shot is an overlay of the two images, I tried to match the scene from the 1D using the free transform tool and then placed an inside stroke to make the edge of the 1D inset shot stand out. Not sure if this is the best way to show the difference in view but I think it works.

Also, I have included the individual shots seperately, both sized to 800px.

Holy cow, that is useful, thanks Keith! You wouldn't happen to have the 17-40 handy, would you? :-)

Oh, and I've got some great news - I've got the same grill!

Cheers
James

When I get a chance later today I will re-do the test with the 15mm and the 17-40 on both cameras.

I LOVE my Weber Genisis, I bet you have some good Texas BBQ recipes...maybe an idea for a new thread

An appreciable difference. Thanks for posting.

When the 15mm FE is on the 1D II I would think that despite having a narrower field of view that you are also cutting off the least sharp areas of the image and end up using the best part of the lens for the image. Also the narrower FOV I would think would be an advantage for Macro unless you enjoy cropping your full frame images