topic Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry in EOS DSLR & Mirrorless Cameras

EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

damisandwich — Sat, 22 Feb 2025 13:16:58 GMT

Hello everyone, i recently got a 90D from a pawnshop and i noticed something was different about the viewfinder. I'm not able to see the AF points or any of the other details like the flicker warning or the gridlines (i turned them on in the menu, still unable to see). Another thing is, it's very grainy and blurry to look through. The red light that flashes when in focus flashes the whole screen.

However, when i take a photo through the viewfinder, its in focus on the LCD screen.

Is this a viewfinder issue or is it just dirty?

video of the red light and grainy/blurry viewfinder

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

deebatman316 — Sat, 22 Feb 2025 13:22:24 GMT

Did you adjust the viewfinder diopter for your eyes. The AF Points can be turned on and off in the camera menu. The EOS 90D doesn’t use a regular focus screen. Instead it uses an LCD overlay in the viewfinder. When the battery is removed from the camera the viewfinder darkens by about 2 stops. Then it also looks grainy too and all information such as the current AF points disappear.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

damisandwich — Sat, 22 Feb 2025 15:42:57 GMT

Thanks for the quick response!

i did adjust the diopter, however theres no change. At the moment, i think its an issue with the LCD overlay. Where would i find the option to turn on the AF points in the menu? i'm not finding anything.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

deebatman316 — Sat, 22 Feb 2025 15:51:23 GMT

You can find that under the AF section in the camera menu.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

damisandwich — Sat, 22 Feb 2025 21:20:20 GMT

i did find the option, however i'm still unable to see the points. Is there any way to replace the LCD overlay in the viewfinder (Via camera repair shop or by myself)?

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

Waddizzle — Sat, 22 Feb 2025 21:25:50 GMT

If you don’t see much of anything in the default shooting mode, Green A+, then there’s an issue with the camera.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

deebatman316 — Sat, 22 Feb 2025 21:37:10 GMT

Green Square (A+ Mode) doesn't show the AF Points when idle. I personally setup my camera to display ALL AF Points whether they're active or not. But the LCD overlay definitely looks like its malfunctioning. Now the whole viewfinder will flash red when focus is achieved. But an AF point that's in focus will appear in the VF. You can't completely turn off the AF Points. I also tried to replicate the problem on my camera the EOS 5D Mark IV when in focus an AF Point appears. In Auto Mode no AF Point display at all until focus is achieved.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

deebatman316 — Sat, 22 Feb 2025 21:38:01 GMT

It can be repaired by Canon but get a quote first before repairing.

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

damisandwich — Sat, 22 Feb 2025 22:51:15 GMT

is it possible to replace the LCD overlay in the viewfinder? or is there replacement parts online?

Re: EOS 90D viewfinder shows no AF points, flicker warning, grid lines, is grainy and blurry

deebatman316 — Sat, 22 Feb 2025 23:03:56 GMT

I’m not sure if it can be sourced online. I wouldn’t recommend DIY repairs. Canon has the knowledge of their cameras and how they work. I’m not sure if it’s even user replaceable.