5D Ee-S and f/4 lenses

So the Ee-S is recommended for f/2.8 or faster, but people say that it is still usable with f/4 lenses. I don't know what "usable" means though, so does anyone know how the viewfinder with an f/4 lens compares with a crop camera viewfinder?

I'm not really clear what you're asking here.

The 5D works wonderfully with f/4 lenses. When people say "usable" they usually mean suitable for most lighting conditions, bright enough to allow good/accurate AF, things like that. F/4 on a FF is the same as F/4 on a crop unless I'm misunderstanding your question. Please clarify.

^ I'm talking about the Ee-S focusing screen, the one that's supposed to make it easier to manual focus.

Shouldn't be a problem. I put the Ee-S screen in my 5D for use with my older MF alternative lenses. I can easily get manual focus when stopped down to f/8 in good light, but that's about the limit. Then again, MF lenses have a nice, long focus throw so its easy to "dial in" the focus. The MF ability of AF lenses leaves a lot to be desired due to the extremely short throw.

EDIT: Just noticed that you're asking about a crop camera. The small VF will definitely give you problems if the light isn't ideal. Besides (unless I'm mistaken), the Ee-S screen is for the 5D only, not the 30D. There are aftermarket screens (Katzeye, Brightscreen, etc) that are more suited for crop cameras and their smaller (and darker) VF's.

Firstly, argyle is correct, the Ee-S is for the 5D, not the 30D. I think that the xxD screens are Ef-S. I bought both a grid and precision screen for my 5D. The Ee-S one just made my viewfinder too dark for my liking when using my 17-40. I also hardly ever manually focus, so I sent the Ee-S back. If I had to guess about how much darker it made the viewfinder, I'd say probably around a stop. So if you want to see how dark the screen will look on your camera, attach an f/4 lens to your body, set your aperture to 5.6 and hit the depth of field preview button to see what your viewfinder will look like. Keep in mind that all of your lenses show the image wide open through the viewfinger, regardless of aperture, until you hit the preview button.

Yeah, I know the Ee-S is only for 5D, I just wanted to know how dark the viewfinder on a 5D would be with an f/4 lens, with a crop body as a standard to work with. But either way you guys answered my question, thanks. Never thought to use DoF preview.