There’s lots of useful information presented to you in a camera’s viewfinder, and I see so many people on my workshops not using that information to its full potential that I’ve realised that many people have glossed over some fundamental camera craft and have not adjusted their viewfinders to suit their eyes.
This article specifically talks about the viewfinders of Canon EOS cameras, and refers to Canon accessories. But the underlying information is applicable to all cameras with eye-level viewfinders.
Reticulated Giraffe argument (A2_092175)
Calibrating the diopter
What we want to do is adjust the camera so you can clearly see the LCD display at the bottom/sides of the viewfinder, as well as the AF points in the centre. For most people’s eyes this should be straightforward.
First defocus the lens completely. Even better, take the lens off for a minute so all you can see through the viewfinder is a bright haze. While looking through the viewfinder (with the camera on) concentrate on the black AF points and the green digits displayed at the bottom. They should be in focus. Adjust the viewfinder’s “diopter” via the small dial at the upper right of the viewfinder (you can manipulate it with a fingertip while looking through the viewfinder). It’s important to either have the lens removed or dramatically out of focus (you might need to select manual focus for this) so you’re not distracted by the background image during the adjustment.
EOS cameras tend to have in their specs that they can be adjusted from -3.0 to +1.0. However, these numbers might not match the diopter numbers you use for your glasses. When I started using reading glasses last year (a sign that time is catching up with me!) my doctor suggested I get simple (and cheap) “+1.5” glasses from the pharmacy, and he was right. These work well for me. But the comfortable setting for both my EOS cameras is not at either extreme of the dial (which +1.5 would seem to indicate): it’s somewhere in the middle. Whatever: as long as it works!
If this adjustment isn’t enough, Canon does make extra fixed diopters, with ratings from -4 to +3 (or maybe more, I’m not sure). These replace the standard eyepiece (in some cases you need to transfer the rubber surround to the new eyepiece) and add to (or subtract from) the internal diopter adjustment. The “Eg
” diopters are for the 1D and 7D cameras, while the “E
” diopters are for most other EOS cameras (there are also “Ed
” and “EE
” diopters for earlier film EOS cameras).Relevant links: extra “EOS diopters” at B&H, Canon EOS 7D manual.
With the diopter correctly adjusted for your eyes, unless you have more-complicated vision issues you should be able to clearly see the important shooting parameters without taking your eye from the viewfinder. And when the image in the viewfinder appears in focus: it probably is!
On my cameras I can see and adjust the shutter speed, aperture, ISO, exposure compensation, flash exposure compensation, and AF points. I can see if the camera’s selected the “wrong” AF point. The camera also tells me things like the remaining buffer size and battery level. Being able to see and control these things without having to take your attention away from the viewfinder and away from your subject frees you up to be able to concentrate on the content of your images.
Do you wear glasses?
I only use reading glasses (or non-prescription sunglasses) so I’m comfortable with this setup. I can take my eye away from the viewfinder and see the world “normally”. But some people need glasses for that, and may feel more comfortable wearing their glasses while using the viewfinder. Bi-(or tri)-focal glasses would complicate the issues, but I can’t talk from experience on that.
After you’ve adjusted the viewfinder’s diopter so you can see the AF points clearly with your glasses on, ideally you should still be able to see all of the viewfinder (including the numbers underneath). If you have trouble with this, you might investigate the Canon EP-EX15 Eyepiece Extender
, which fits between the eyepiece and the camera, with a lens in it to allow you to still see the whole viewfinder. It’s purpose is to partly move your face back by 15mm, but it also reduces the viewfinder magnification by 30%, which may help some glasses wearers.
I don’t use one of these: I like all the viewfinder magnification I can get, and I don’t mind getting sunscreen and oil from my cheek and nose (or condensation from my breath) on the back of the camera – I simply wipe it off when necessary. But it might suit you.
Speaking of configuring your viewfinder, it might also be worth considering the options for alternate focus screens. Canon makes alternate screens for some EOS cameras which superimpose a faint grid across the vewfinder. I use one of these (the Eg-D) in my EOS 5DmkII, but my 7D doesn’t need this: it has a switchable grid via an LCD panel in the viewfinder. For further information on these screens, see my 2009 Straightening photos post.
Red-billed Hornbill and elephant dung (A2_091361)
In a perfect world, everyone would know all this stuff already. But hopefully this article has either taught or reminded you of something useful to do with your camera craft!