Oversized Viewfinders or Other Solution?

[pcacj]

My eyesight requires that I wear glasses, although I'm not too bad off. I seem to have a recurring struggle with shots being in focus. When I use my 50mm f1.4 I expect that a slight miscalculation will cause an out-of-focus shot but it looks perfect in the viewfinder. I have struggled with this from day one and feel there must be a solution that takes into account people with slightly poor eyesight. Is there a company that can modify a viewfinder or fit an enlarged viewfinder on my Canon XTi ? Is there another solution that some of you who wear glasses have used? Thanks for any assistance.

 

[C-Towner]

Have you adjusted the diopter?

I wear glasses, and it took some doing to figure out what the correct setting of the diopter showed what was correct.

If you do get a magnifying eyeful, if the diopter is incorrectly set, you will still have th same problems.

 

[pcacj]

I have not checked the diopter...was not aware that I can change this. Will go look now.

 

[bentcountershaft]

I have the same problem. With the diopter adjusted all the way to the negative side it still isn't quite enough. I feel like if there were two more clicks in that direction it would be perfect.

 

[pcacj]

Checked the adjustment on the diopter and it was in a good spot for my vision. I played with it to see if there were better settings. Not much range there. I did find two web sites that sell split screen focusing for the XTi....

Focusing Screen

http://www.katzeyeoptics.com/item--Canon-400D-Focusing-Screen--prod_400D.html

 

[Dwig]

Checked the adjustment on the diopter and it was in a good spot for my vision. I played with it to see if there were better settings. Not much range there. I did find two web sites that sell split screen focusing for the XTi....

Focusing Screen

Canon 400D Focusing Screen - Katz Eye Optics

If you can adjust the eyepiece diopter past the point of "best image" in both directions then you're able to adjust is for your eye. Be sure to do the adjusting in very dim light so that your eye dialates (opens to its widest f/stop) for the most critical adjustment (your eye's least DOF).

Modern AF cameras have screens optimized for viewing and not for focusing. Most are actually rather horrid as focusing screens. The old dimmer screens were actually far better for focusing. The other "fix" is to get a modern screen with a split image prism or microprism (actually many small split prisms) focusing aid in the center.

 

[dxqcanada]

Pentaprism is small ...

Many of the newer DSLR's have a nice full size pentaprism (like the old days) ... Canon 7D, Sony a900/850, or Pentax K-7 ... etc.

... hmm, a split screen would help.

 

[Derrel]

I bought the Nikon DK-17M eyepiece magnifier, which replaces the normal, non-magnifying dust barrier eyepiece on the professional Nikon bodies; that is the DK-17, without the M suffix. Canon has an "eyepiece extender" device that fits over the stock Canon eyepiece, utilizing the slide-in channels that hold the rubber eyeglass protector, causing the eyepiece to stick out kind of far...I looked at it a few years ago, and my impression was that it was kind of cheesy. Your mileage may vary. perhaps there is a dedicated Canon eyepiece *magnifier*, like the Nikon DK-17M, which would fit on your D700 body.

Nikon | DK-17M Magnifying Eyepiece for D3, D2 & D1 | 4793

 

[Big Mike]

Are we talking about manually focusing or using the camera's AF?

If the shots are not in focus when you are using AF, then it's likely a calibration (lens and/or camera) problem. Although, there is still room for user error so you'll have to eliminate that to be sure about the gear.

If you want to be able to see better, so that you can manually focus the lens...that's a different issue, and that's where these focus screens & viewfinder accessories will help.

Pentaprism is small ...

Actually, don't these entry level DSLR cameras use a Penta-mirror, and not a prism at all? It makes the camera smaller and lighter, but (I think) sacrifices the size & brightness of the viewfinder.

 

[Garbz]

It's often not the size of the prism / mirror and to do with the optics of the viewfinder itself. The D700 pentamirror's assembly is the same size as a Nikon FE, yet visually the viewfinder is FAR smaller. Magnifying eyepieces are a solution to this problem.


On the topic of split prism focusing screens I have a Katzeye variety and love it. I have a few manual focus lenses and it's a godsend helping me to get quick and accurate focus every time. However I think in this case it may be masking an underlying problem for you. The focusing screen and the sensor have the same distance to subject (via mirror). So if something is in focus in your viewfinder then it should be in focus on the sensor. By adjusting the dioptre you directly adjust your ability to focus on this screen and the rest of the viewfinder, and it's the equivalent of wearing glasses.

So as far as your vision is concerned. If you're having problems and attributing them to your eye the only issue really is the dioptre adjustment is wrong. If it is in fact right and pictures look sharp in the viewfinder and come up blurry in camera, then your focusing screen or reflex mirror may be out of alignment (not unheard of in camera world)