Rebel t7 live view is darker than reality

[jakus4]

So I've been using a helios 44m lens with my rebel t7 (2000d) for a few months now, and everything was perfectly fine until today. I was using the kit lens yesterday and just switched back, and now the live view isn't the same as the photo it takes. With auto iso everything is perfect, but as soon as I manually set it to anything, live view just darkens everything. The exposure meter works just fine. And without live view it's really hard to shoot mf. With the kit lens everything is fine

[jrhoffman75]

Are the manual settings you are using the same as the camera selects with Auto ISO? Is there an option for exposure simulation that needs to be turned on?