How to Enable Flash w/Accessory in Shoe

I have this cheapy flash diffuser for my T3i that has a tab that fits in the flash shoe. Unfortunately, the camera disables the internal flash when there is anything in the shoe thinking that must be an external flash.

Is there any way to enable the internal flash when the shoe is occupied?

There is a little switch under one of the rails of the flash shoe that senses when an external flash is mounted and disables the internal flash. One way I can think of to override the switch would be to clip out a piece of the flash diffuser so that the diffuser does not trigger the switch.

I doubt that would work if the T3i hot shoe is typical. The switch is under a leaf spring which runs the length of the shoe rail; the whole spring is depressed flat when flash or accessory is inserted.

I can't see an easy solution; you may have to ditch the diffuser - and consider buying a cheapo flash gun.

It does work on some Canon cameras, at least, to cut off a part of the hot shoe attachement of whatever you are putting there.

But a real flash in the hot shoe would of course be an improvement.

On the 60D it is a microswitch with a button that is about 1/16 inch in diameter. Looking at the back of the camera, the button is in the right side rail and about 2/3 of the way back to front. Like gjl711 suggests, if a cutout allowed that button to be up, then it would work as desired. See if the T3i is similar.

It's gotta be possible. The Gary Fong Puffer works in Rebels.

http://www.garyfongest​ore.com …iffuser.html#.U​Dto24l5mc0

Way back I wanted to use a Nikon SG-3IR on my 7D to stop the onboard flash firing into the picture. I took a look at the GF puffer, I saw all you need to do is file a small step out of the bottom edge of the foot (both sides) so it misses the stainless steel spring of the shoe. This is the part that operates the switch. This mod will work for any accessory fitted in a hotshoe.

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