Canons and flashes......


Active Member
A long time ago in a galaxy far away...............

I had a canon T70 (still have, in fact !)

I also had the 299T speedlite.

Now I have the 40D.

Q - how can I use the 299T with the 40D. I know they wont totally communicate with each other,.
I tried a few times but it is always overexposed.

Anybody try this before ? Any ideas ?


Distinguished Member
Check here , one of the best references for EOS cameras and flashes I have read.

Flash Photography with Canon EOS Cameras - Part I.

If the flash model number does not have an E in it , it wont work properly with an EOS system , its in this section. All it will do is trigger at full power.

Older Canon Speedlite flash units.

Older Canon Speedlite flash units which lack the letter E in their product name were not designed for EOS cameras. There were Speedlite A models (eg: 199A) for old A-series Canons such as the A1 and AE1 and Speedlite T models (eg: 277T) for T-series Canons such as the T50 (but not the T90) and various other special-purpose models.

You can put these older flashes on your EOS camera and they'll trigger OK when you take a photo, but they can't use modern automated flash metering. So you have to either use them in auto mode if they have such a setting (set your camera to a shutter speed up to the camera's X-sync), dial in manual power and calculate the flash distance yourself if they have manual controls or else expect the flash to fire at full power.

I don't know if all earlier Speedlite products have safe triggering voltages or not. The list maintained by Kevin Bjorke on his Web site suggests that T series flash units are OK and most A series and older flash units are in a grey zone, but you should probably check for yourself.

The one exception is the 300TL flash unit. It was designed for the old Canon T90 camera, and its more advanced features (such as its versions of FEL and second-curtain sync) are not supported by EOS cameras. However it can be used with EOS cameras as a basic TTL flash unit even though it lacks an E designation.
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