5D prism and onboard flash issues73x

[Elgsdyr]

Michael, in the 5D Field Report you state that: "The 5D's full-size prism doesn't leave room for [a pop-up flash], and so the Canon 1 Series, and now 5D camera, don't feature pop-up flash. It's as simple as that."

While this may make sense comparing the camera to APS-type DSLR's it doesn't make sense when comparing to film cameras, which are - by "nature" - all full-frame. I have a Minolta Dynax 7, which has a 92-94% 0.8x viewfinder (compared to the 5D's 96% 0.71x VF) AND an on-board pop-up flash. The "full-frame" prism doesn't prevent it here. Also look at the Minolta Dynax 9, which has a heavy duty weather-sealed pro body, a 100% 0.73x viewfinder, and an on-board flash. No problems there, despite being a "full-frame" 35mm film SLR.

And looking at the design of the 5D, I see no reason why there shouldn't be room for pop-up flash. The part of the flash that takes the most space (the flash itself) is usually placed in front of the prism, where the 5D seems to have room (it lacks the "nose" of many other (D)SLR's).

IMHO, it's not a question of wether there's room or not. It seems to me like Canon have made a decision that a pop-up flash does not belong in a pro body, despite the obvious reasons for it's usefulness. Just like their decision that the mirror lock-up feature must be buried deep into the menus despite the loads of complaints from its users.

[Elgsdyr]

- and I don't know how that 73x ended up in the topic... Just ignore it... ::

[bangaio]

Just what I thought, it aint weather sealed but my eos 100 (elan) has a nice pop up flash (and it zooms too)!  The eos 5 had one too, shame they missed it out really just for a little bit of fill in when needed.

[Jonathan Wienke]

Pop-up flashes are generally useless. The flash is so close to the axis of the lens it's highly prone to causing red-eye, and if you're using real lenses like the 24-70/2.8L instead of the consumer-grade coke bottles, the barrel of the lens causes a very noticeable shadow on the bottom of the frame. Given that 5D users are far more likely to use real glass than DRebel owners, the absence of a pop-up flash that causes more problems than it solves will not be sorely missed. If you want a really small, light fill flash, get a 220EX.

[howard smith]

I find the pop up flash on the 20D very useful for triggering other flash units.

[Jonathan Wienke]

How do you disable the E-TTL preflash and avoid premature triggering? Or do you smart triggers that ignore the preflash?

[leonvick]

Michael, in the 5D Field Report you state that: "The 5D's full-size prism doesn't leave room for [a pop-up flash], and so the Canon 1 Series, and now 5D camera, don't feature pop-up flash. It's as simple as that."

IMHO, it's not a question of wether there's room or not. It seems to me like Canon have made a decision that a pop-up flash does not belong in a pro body, despite the obvious reasons for it's usefulness. Just like their decision that the mirror lock-up feature must be buried deep into the menus despite the loads of complaints from its users.

Whadaya mean by "doesn't belong?" Are WE, the customers no longer who decide what features belongs in our equipment? IMHO, the arrogant decision Canon and Nikon have made is that customers might buy more flash accessories if none is built into a camera. They may be right, but I'll be darned if I'll buy their brand of flash to fill in for what they leave off. I have been kicking myself for the last two years for buying a DSLR without a built-in flash and swear I'll never do it again, for all the reasons that make pop-up flash so useful and detachable flash so clumsy. We may attribute noble reasons to a camera maker for leaving off such a major feature, but we all should know that the only reason they do anything any more is for profit.

[howard smith]

How do I disable the E-TTL preflash and avoid premature triggering?  I guess I didn't know this was a problem.  I set the camera to manual and used modeling lights for high ambient lighting (for focusing and composing).  I have never noticed the preflash, and I guess the slaves don't either.  I hope this still works now that I know it's a problem.

[Anon E. Mouse]

We may attribute noble reasons to a camera maker for leaving off such a major feature, but we all should know that the only reason they do anything any more is for profit.

Or perhaps with consumer emphasis on price, they left it off the camera to comply with that requirement.

[Jonathan Wienke]

How do I disable the E-TTL preflash and avoid premature triggering?  I guess I didn't know this was a problem.  I set the camera to manual and used modeling lights for high ambient lighting (for focusing and composing).  I have never noticed the preflash, and I guess the slaves don't either.  I hope this still works now that I know it's a problem.

E-TTL flashes fire a metering flash just before the mirror lifts so that the camera can calculate appropriate flash exposure. The metering flash goes off about 10-20ms before the exposure flash, and is generally less powerful than the exposure flash, but it is usually powerful enough to trigger optical slaves, which means that they are still recycling during the exposure flash and are unable to fire again that quickly. This is a frequent source of bafflement because the photographer sees the slaves fire, but they do not contribute to exposure whatsoever, and most people don't notice that the camera flash is actually firing more than once. There are "digital" optical triggers that are smart enough to ignore the metering flash, but if you're not using them then you're simply lucky and your modeling lights are bright enough to blind the slaves to the low-power metering flash. Try turning off your modeling lights and see if everything still works. You may be rudely surprised.

[howard smith]

As long as it works for me, I see no reason for the rude surprise.  I will keep all this in mind should luck fail in the future.

OK, I tried it.  It works fine as long as the strobe slave does not see the 20D flash directly from the camera.  That may be where the preflash isn't strong enough to trip the slave, but the main flash is.  Nice to know.

Add:

I added a small reflector taped to the camera to bounce the flash before it hits the slave.  Works fine.