I get some heavy black thread and wrap it around the groove the eyecup slides on to. Just a few times around does the trick, although it will vary with the thickness of the thread you've got. When you slide on the eyecup, the little tangs will grab the thread fibers and it will stay in place.
Others have used black silicone glue, or gaffers tape. They all seem to work OK.
A plastic piece of the fairly cheap built eyepiece of my Rebel XT came off and this lead to a constant loosening of the eyepiece. I just used some drops of glue to permanently fix it in place.
BTW, it's funny how we all have our little "issues" related to how we insert/remove equipment from the bag. I've never lost an eyepiece but the mode dial on my xxD bodies invariably moves out of position and my first reaction to this is "OMG, my camera has gone kaput." Finally after many heart attacks from a moving mode dial I've resorted to gaffer tape and my little problem is solved.
I've never had an eyepiece come off, or lost one. Been shooting Canon for several years and had many new and used cameras. Heck most times I have trouble getting it off the camera when I want to wipe down the view finder.
STARRIDER wrote: glue it on..you wont lose it then..why would ever need to take it off..
As I mentioned above, yes, I also glued the eyepiece on my Rebel XT camera. But there is one reason why you might reconsider doing this - I evaluated options to convert my older Rebel camera for IR shooting. It is recommended here to remove the eyepiece to open the camera body. In the end it was no issue for me since the conversion would have costed a lot more than this camera is worth meanwhile.
STARRIDER wrote: glue it on..you wont lose it then..why would ever need to take it off..
In theory you're supposed to slide the eyepiece off and use that little rubber bit of the Canon strap whenever you're using a tripod as "stray light entering the eyepiece can affect the metering" - however having never had an issue with this and being on my 7th eyepiece for my 2 year old 40D, I can confidently say that, for me, the PiTA factor of losing it comprehensively outweighs the tiny little theoretical benefit of being able to take it off.
Chris Beaumont wrote:
In theory you're supposed to slide the eyepiece off and use that little rubber bit of the Canon strap whenever you're using a tripod as "stray light entering the eyepiece can affect the metering" - however having never had an issue with this and being on my 7th eyepiece for my 2 year old 40D, I can confidently say that, for me, the PiTA factor of losing it comprehensively outweighs the tiny little theoretical benefit of being able to take it off.
Good work Chris..thats what i mean,glue the little devil and forget about it..think i'm gonna go take some photo's now..
STARRIDER wrote: glue it on..you wont lose it then..why would ever need to take it off..
Probably pointless for the newer bodies with live-view ... but the one I use for macro shots frequently - almost never has the eyecup on. I put the angle-finder pretty frequently there.
Gluing it on is a pretty bad idea, IMHO. Consider that over time, the eyecup pad will crack open, rendering it sharp and painful to rest your eye against. Also the hard plastic strip that lines the bottom of the eyecup may break off and you'll want to replace it. I've had this break on one eyecup and actually protrude forward towards the eyeball. Yikes...
So yeah, keeping it on is very important (I have yet to still find an adequate solution, but I like the black thread trick) and I've lost a good 4 or 5 different eyecups, both Canon and third party. Gaffers tape doesn't seem to be enough. Something more fixed but not quite as permanent as glue would be ideal.