This is my description of what the functions do based on my experience, so I definitely recommend checking out the manual if you have any detailed questions; this guide is just some help with what they do and suggestions for use. There's no warranty here, this is just based on the cameras that I own; use at your own risk.
This page is for an EOS5, and there's a page for my Elan 7 as well. Remember that these only work in creative mode, and not in any of the program modes. This is actually handy, because if you're tossing your camera to your wife or grandma to take a picture of you in front of the Eiffel tower replica in Vegas or something, you don't have to try to explain CF4 to them...:-)
EOS 5 custom functions
| CF | Description |
|---|---|
| 1 | High speed film rewind; I almost always have this one on. It makes it louder, but still pretty quiet. |
| 2 | Leader out rewind. Useful for changing film types. Before I had two bodies, I always had this one on, just make sure to be methodical about handling the film so you don't expose a roll twice. |
| 3 | Cancels DX film-speed setting. You can always override it, so I'm not sure why you'd want to turn this one on... |
| 4 | My favorite! Autofocus moves to the "AE-lock" button on the back. No more accidental autofocus when shooting a picture. |
| 5 | Forces you to re-meter after each shot; no returning to half-way down on the shutter button then shooting again. Never used it... |
| 6 | Makes the AE-lock button stop autofocus in case you decide you like where things are focused. Doesn't work with CF4. Never touched it... |
| 7 | Turns off the AF-assist light. This is one that's probably handy, but since I never know what it is, I never get to use it... |
| 8 | If you're making a bunch of multiple exposures, this can be useful. Makes the camera stay in multiple-expsoure mode after each shot, so you don't have to set it back after each exposure. |
| 9 | A very important one; makes the flash the primary light. The shutter speed gets set to 1/200, which forces the flash to pump out enough light to light the scene on it's own. This one is on a lot for me (in conjuction with my external flash). |
| 10 | Stops the autofocus boxes from turning red when focused. Not sure why you'd want to disable this, so I've never used it. I find it handy to know where the camera is focused, but this one is strictly personal prefrence I suppose |
| 11 | Turns AE-lock into a depth-of-field button. Totally cool, but doesn't work with CF4 (for obvious reasons). This is why I bought the eye control version, so I could use the little parallelogram for depth of field, but it doesn't work vertically on this camera, and I really just never used (successfully at least) that depth of field control; not reliable enough for me. |
| 12 | Mirror-pre-fire. Use this a lot with a tripod. Once you're in self-timer mode, the mirror fires early to let vibrations die out then, then the picture fires. Kind of like mirror lock up; just as good in my experience, all though I don't have any really long lenses where it might make a significant difference. The warning here is to not point your camera at the sun when the mirror is up, because the sunlight will get focused on the shutter and do bad things to it. The manual uses the word "scortch", which sounds bad to me. |
| 13 | Makes the meter turn off immediately after taking your finger off the button. Saves battery, but seems like it would make the thing a real hassle to use; maybe not though, as long as AE-lock still holds it's timer...I'll have to check that out. |
| 14 | Makes the flash fire at the end of the exposure instead of the beginning. Useful for long exposures at night. I'm sure you can find a tutorial somewhere on the internet about why this would be useful, but basically it makes the streaks of headlights, or whatever appear behind the lit-up thing instead of in front of it. |
| 15 | Links the spot meter to the autofocus frame. |
| 16 | Disables some hunk of flash reduction which normally kicks in with backlit subjects. I'll have to play with this one, since I've never used it, and am not really sure what the difference is. |