Why is it so that, in certain bodies, only 90, 92 (and so) percent of viewfinder is captured on the film. Even in high bodies like EOS 3 100% is not covered. Why is it so? Is it not possible to add this feature in all bodies. Or aleast a mark should be added so that one can understand how much of the viewfinder will be captured on the film. What do you think ?

-- sajeev (chack74@yahoo.co.in), April 19, 2002

Answers

Actually, you have that backwards: it's 90-92% of the film that's visible in the viewfinder, not vice versa. So you can see that it isn't possible to add a mark to the viewfinder to show where the edges of the film are ;). I don't know why the entire frame (or more of the frame) isn't visible, but I'll bet it has something to do with cost.

-- Curt Hagenlocher (curt@hagenlocher.org), April 19, 2002.

The EOS 3 is 97%, which in the grand scheme of things might as well be the full frame. The 3% difference would be very hard for you to see in practice, and you can always crop the picture when you print.

Rangefinders (like Leica M) have frame lines, but these have to change based on the focal length of the lens. The lines for 28 mm are different than those for a 90 mm. But you are looking through a separate viewfinder and not through the picture-taking lens, so the lines are critical. That special viewfinder actually shows you more than 100%, so you can see where the frame will crop. And since there is no mirror, you see the image while the shutter is snapping (no blackout).

A 100% viewfinder in an SLR is nice but not terribly critical--since you can't see past the edges. A 110% viewfinder (with framelines), for example, would require a huge mirror--which adds to overall size and weight of the camera, noise from the mirror-slap, etc.

-- Preston Merchant (merchant@speakeasy.org), April 19, 2002.

>Is it not possible to add this feature in all bodies.

Of course Canon could build all their SLRs with 100% viewfinder coverage. The cameras would be bigger to accommodate the larger prisms and would cost a lot more. So they don't.

-- NK Guy (tela@tela.bc.ca), April 19, 2002.

One hundred percent viewfinder accuracy is overrated. I used Nikon F, F2 and F3 cameras for years with 100% viewfinder accuracy. I often composed so tightly the photos could not be cropped by editors without killing the composition. Sometimes even the slide mounts cut off part of the image I had composed. I saw improvement in my photos using a Nikon FM which was <100%. Now, my EOS bodies are all <100% and I shoot looser compositions within the framing. My results are better without 100% viewfinder accuracy.

By the way, I never could get the hang of the Leica rangefinder viewfinder. My photos were always surprises. Not just in viewfinder accuracy but in perspective. The frame lines cover the approximate image area of the lens but the finder does not show the perspective of the lens. It was not a good tool for composition, in my opinion.

-- Lee (Leemarthakiri@sport.rr.com), April 19, 2002.

Notice that in general the more expensive the Canon, the more coverage you can see. ;)

I personally haven't found a real need for 100% coverage since most pictures are going to be cropped a bit -- especially if you like 8x10s.

-- Steven Fisher (steven_fisher@hotmail.com), April 19, 2002.

a good discussion about viewfinder Vs Picture Coverage. well, if the cost of bodies increases drastically just by incorporating that 3-10% of viewfinder, then they can atleast give a frame lines in the viewfinder covering approximate image area. this is usually found in many compact cameras. this can ofcourse be implemented in any SLR which does not capture 100% viewfinder.

-- sajeev (chack74@yahoo.co.in), April 20, 2002.