Even with an LCD Viewfinder on my 5D, I still have to hold the camera upright like and idiot and get sore. When shooting from a slider you can't use the viewfinder practically. The only time it might be practical is shooting from a tripod.canon, nikon, 5d mark ii, mark iii, 7d, t2i, t3i, t4i, t5i, d90, 60d, 70d, 6d, d600, d800, dslr, HD, video, movie mode, LCD screen, pixels, viewfinder, optical, digital, sensor, electronic, 21mp, 18mp, resolution, zacuto, hoodman, loupe, cowboystudio, ezphoto, GGS Perfect foldable, swivel screen, opteka, letus hawk, zeikos, seagull, cavision, phillip bloom, cinematographer, cinematography
DSLR LCD Viewfinder Review - They've been around for a long time, and I finally got one
Actually, I do know why I haven't acquired one until now: these LCD viewfinders sort of epitomize why DSLRs are impractical for shooting video. Any camera where you have to buy an external viewfinder loupe just to see the LCD screen on the back is impractical, especially since there are no right-angle LCD viewfinders so you can shoot in a standard, comfortable way.
Even with an LCD Viewfinder on my 5D, I still have to hold the camera upright like an idiot and get sore. When shooting from a slider you can't use the viewfinder practically. The only time it might be practical is shooting from a tripod.
The "Professional 3" LCD Viewfinder for 5d Mark ii" - New, $45
The one I chose is the only one on amazon of its kind. Check it out here. It's called the "Professional 3" LCD Viewfinder for Canon 5d Mark ii."
I love that the maker of this finder aren't BSing around and branding this with some fancy Italian name. It's just a plastic box with a simple lens in it that lets you see better. That's it. And it really does work well. I've read some reviews of $100+ VFs that people are saying don't work well. The Cavision brand one comes to mind, and it runs at least $150.
This is the only LCD VF designed with a frame that fits over the regular optical viewfinder of the 5D. Once you slide the frame over the 5D's viewfinder you then snap the LCD VF into place. It is a plastic on plastic snapping mechanism that keeps it in place and seems to work surprisingly well. I'd be scared that this all-plastic construction would eventually cause it to fail, especially with frequent daily use and in colder weather.
Like most of these VFs, this "Pro" VF is made of plastic. The optic inside that gives you 3x magnification of the LCD is heavy and makes the VF lopsided. This weight lets you know that it's real glass. The diopter switch moves the optic forward and back, giving you less or more amplification of the LCD. I have no idea if this will actually help those with glasses.
The eye cup is the worst aspect of this VF. If doesn't have any grooves to snap into place, thus it hangs on just by a slight tension, and falls off frequently. A little gaffers tape could help this.
5D Mark ii with the "Professional 3" LCD Viewfinder for 5D Mark ii"
When you look through the VF you realize that it is a quality optic. The LCD is beautifully magnified and it's crystal clear! No complaints at all. It really does help when shooting outdoors in broad daylight, and will even help to conserve battery power because with the VF you don't need the LCD brightness set at max.
The bonus item - "Angle-Changing finder"
The "Professional 3" LCD Viewfinder for Canon 5D Mark ii" comes with another little bonus item. Basically a waist-level finder, the "angle-changing finder" as it's called in the description on amazon, really does work. It uses two mirrors to change the angle, giving you the ability to shoot from above the camera. This in theory is actually almost more useful than the VF itself because it allows you to shoot without having to have the camera at eye level.
The downfall of it is that the image is not amplified so you will have a tough time seeing the entire image from a few feet above, as well as seeing if it's in focus or not. Thus, this little item is neat but not really perfect. It's also made of the same plastic and cheap mirrors that inevitably will fail with lots of use.
Overall, I recommend this VF for someone who wants a VF for their 5D Mark ii that can quickly and easily be mounted and removed. No other VF is as easy as this. The other VFs that use frames are glued to your camera's LCD (no thanks) and the others are mounted to your camera's tripod hole underneath where you need to mount the camera to a tripod mounting plate, slider, jib arm, or follow focus rig (I can see a million issues associated with mounting a VF this way).
This VF on other Cameras
One of the reviews on amazon states that this VF can also fit on a Canon T2i. If this is true, then this should also fit the T3 and T4 and possibly the T1i and because they are practically the same as the T2i. I can't guarantee that it fits any camera other than the 5D Mark ii. If you have amazon prime, just order one and see if it fits. If not, you can return it easily.