The Elan 7e is a wonderful camera and $35 for one is a real steal!
I shot with a pair of EOS-3, but also used an Elan 7e at times because it's one of the quietest SLRs... far quieter than the EOS-3!
Regarding lens compatibility.... modern EF lenses should work fine on the 7e. Modern EF-S, EF-M and RF lenses won't even fit onto it and won't work..
There are a couple possibilities....
First be sure the Elan 7e's AF system is set up correctly. It's been many years since I owned or used one, so I forget the details.... but it does have Canon's Eye Controlled AF, which I think was only found on the Elan 7 (two versions), the EOS-3 and the A2e film cameras. This system is designed to track the photographer'seye movement and change focus points accordingly.... in other words, the camera tries to focus where the user is looking. (Not to be confused with modern eye focus in some cameras, which is designed to dedect and focus upon subject's eyes.) It was most successful on the EOS-3 because that camera had 45 AF points... if memory serves the Elan 7e had seven AF points and the A2e only had three.
Download the Elan 7e manual from the Canon website. Consult it and turn off Eye Control for the time being. You can experiment with it later, if you wish. It worked well for some people.... not so much for others (I couldn't use it, perhaps because I wear eye glasses). Also be sure you understand the rest of the setup of the AF system, though aside from Eye Control, it's probably not all the different from your digital rebel.
I agree with previous posts, that it may be with that particular lens the AF system is struggling and cannot focus in lower light conditions. AF systems have gotten better and better over the years, including their ability to focus in low light.
Get out in bright light and try to focus on good, contrasty subjects that have plenty of detail. The EF 75-300mm III is a "budget" zoom that uses a micro motor AF system that's not particularly fast and responsive. Still, in good light the camera and lens should be able to focus.
It also may help if you manually select the center AF point, which on many Canon is more sensitive than the other AF points.
I disagree with some of the previous responses about cleaning the lens' electronic contacts. Done right it is safe to do and sometimes it helps. Those contacts provide communication between the camera and lens for AF, aperture control, and Image Stabilization (when the lens has it, the EF 75-300 III doesn't). To safely clean the contacts on the lens....
- Don't use DeOxit. It's not necessary. Those electronic contacts on the rear of the lens are gold-plated, specifically to prevent oxidization. Isopropyl alcohol is all that's needed. In fact, plain cheap "rubbing alcohol" works fine.
- Don't use a Q-tip or any other type of common, household cotton swab. Those shed tiny, tough cotton threads that can get inside a camera's mechanisms and jam it. Instead use a clean, lint free rag or an optical swab (such as is used for sensor cleaning... Pecs and similar).
- Lightly dampen any dry swab or rag with a few drops of alcohol and gently wipe the electonic contacts on the lens. This will remove any oils on them, which are usually the problem. It's probably finger oils. But also could be from other sources. The communication between lens and camera is done using very low voltages, which is pretty easily interrupted or hindered by anything on those electronic contacts, even a thin layer of oils you can't see.
- Be careful to keep off the optics of the lens and don't get the rag or swab so wet that it might drip inside the lens. Pre-moistened optical/sensor cleaning swabs will work, but are usually way too wet with fluid. Shake off a lot of that and/or let some evaporate before using them for this or amost other purposes.
- Don't use anything abrassive to clean those contacts. That could damage the gold plating.
- Don't use a pencil eraser to clean the contacts. Erasers are made from vegetable oil and are unlikely to remove oils from the surface, might even make matters worse.
- While you are cleaning the contacts on the rear of the lens, also carefully inspect the corresponding pins just inside the lens mount on the camera. Those are spring loaded to ensure a good connection with the lens contacts. Look for any that are "stuck" and not extending as far as the others. You can also test they are free to move by gently pressing on them with a fingernail or something. Of course, be careful of the mirror and other internal mechanisms of the camera and don't drop anything inside the mirror box.
It's true, cleaning those contacts may or may not help the lens focus. But it's quick, easy to do-it-yourself and costs very little to try.
It is possible that a modern lens wouldn't work on an older camera.... But I'm not aware of any and would think the ones that use more modern AF systems such as STM (stepper motor) or the hybrid Nano USM would be more likely to have backward compatibility issues.
If the EF 75-300 III still doesn't work on the camera, you might try a lens that's more contemporary with that camera. Some examples are the EF 28-135mm IS USM, EF 50mm f/1.8 II or EF 50mm f/1.4, EF 35mm f/2, etc. I used some of those lenses on my Elan 7e.
If it doesn't work with other known-good lenses from the same time period, there's probably something wrong with that particular camera. Maybe that's why it only cost $35. I'm sure Canon no longer repairs Elan 7e, but you might find an independent shop that does, if they can get any parts necessary to fix it.
I agree with other responses... It's a little odd that a school is still calling for students to use a film SLR. That's probably just to insure that any camera the student chooses has user controls instead of the heavy "point-n-shoot" styple automation that's found on many digitals... especially the more affordable models. Still, an older DSLR that can be bought for little money... such as the Canon 10D, 20D, 30D.... could give the user very similar learning experience.
Or, maybe they are just insisting on film to force the students to slow down and think about each shot.... to plan instead of just make hundreds of digital shots using the "blind hog gets an acorn" school of thought.
Hope this helps!
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2) some other cameras, various lenses & accessories
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