Digital camera accessories

[lepenser2]

What is a digita flash ? Why can't I  use a regular flash example Sunpak 522 with my Canon 20D?

[bdery]

Hi!

I suppose you mean a Digital flash. I'm not exactly sure what you refer to, but I think you refer to a flash made for digital cameras.

The main difference between flashes made for film cameras and digital cameras comes from the way the flashes measure light.

Film cameras from all brands used a system called TTL (through the lens). This system, which was tweaked by all brands, used light reflected from the film's surface to decide when enough light had illuminated the film, and shut off the flash.

This cannot work easily with digital, because the camera's sensor does not reflect light in the same way. All brands have decided to use the camera's light meter to decide when to turn off the flash. What's more, communication protocols between the camera and the flash have been updated. These newer systems, only valid for digital cameras, are probably what you refer to. Canon's system is called E-TTL.

So if you use a TTL flash on a digital camera, the TTL protocol will not work. You need a flash with E-TTL compatility. However, if your flash has an auto mode (like most flashes dating from the 90"s have) you can still use it in this mode. It will require more tweaking but it can easily be done. I'm currently playing with an older flash that has an Auto mode with my Pentax DSLR, and it's working quite well.

I hope this helps.

[lepenser2]

Thank you for the info. It was very helpful.