50d + Bulb + No shutter release

On my XTI, I was able to take long bulb exposures without a shutter release. I believe I had mirror lockup on, I would press the shutter to open it, then press it again to shut it, and I would get an exposure for however long it was open. Maybe I am crazy, but I thought that was how it worked.

On my 50d, in Manual mode, bulb setting, mirror lockup, if I press the shutter, it stays open, but then closes after ~5 seconds and the image it takes only says 1".

Do I have to have a shutter release to use bulb mode properly? Does not compute.

Mirror lockup lifts the mirror on the first press and takes the picture on the second, you still need to hold the shutter in BULB mode for the duration of the exposure.

AFAIK there is no way around it, so yeh you do really need a shutter release.

Essentially you can release the shutter just as you did. IIRC, you need to hold the release for 2 seconds to initiate the bulb exposure. Once you release you can shut it by pressing the button again. This is how it worked using my remote as well, actually.....

You don't really need mirror lock up for very long exposures..