rodpark2 Loc: Dallas, Tx

This is one of the first things I have students do in class...adjust the diopter. Have the camera autofocus in a contrasty subject, like a sign with text. Next, without moving the camera or touching the release/focus button again, turn the diopter adjustment until the viewfinder image is as sharp as possible. Done. As the day goes on and lighting conditions changes, as well as things like blood sugar, you may need to tweek it from time to time. The diopter has no effect on the final image, rather allows you to see what it's doing or makes manual focusing easier and more accurate. I've had students who exclaimed "Wow" when doing this because they'd never seen a sharp viewfinder image. I'm 74 and wear bifocals so I adjust with my glasses on. There are real advantages to manual focus and even with AF I often need to touch up the focus using the MF override that better lenses provide. Another rough adjustment is to concentrate on any lines or boxes on the focusing screen and change the diopter until they are crisp. Good shooting!

cambriaman Loc: Central CA Coast

I think the previous camera owner had the same vision problems you have and adjusted the diopter. I know because before cataract surgery I had my diopter set for a large amount of correction for near-sightedness (short-sightedness for our friends across the pond) and had to adjust the diopter correction out after surgery.

DonOles

Thanks I appreciate the reply and the helpful information. Have a great day.

MARIDLEY

Adjusting the viewfinder clarity:
Remove the eyecup:
While grasping both sides of the eyecup, slide it up to remove.

Make the adjustment:
Turn the knob left or right so that the AF points in the viewfinder look sharp.
Reattach the eyecup. Do this with your glasses on.

If the camera's dioptric adjustment still cannot provide a sharp viewfinder image, using Eg-series Dioptric Adjustment Lenses is recommended. Download a manual at CANON'S website if you don't have one. Use the manual for more information. Also check to see if the latest firmware is installed in your camera.