Pop-up flash strobes on Canon

olafurdanielsson · January 6, 2011

Hi
Just got one simple (I hope) question. I hope this is the right category for this question...

Sometimes when Canon users are taking photos with pop-up flash, it seems like the flash strobes many times before the picture is taken.:dunno

1. What is that?:clap
2. What is it for, or what does that do?:ivar
3. Is in also possible or Nikon, or does Nikon have something else in stead?:barb

With many thanks in advance.

ÓD

adbsgicom · January 6, 2011

Might be that they have red-eye reduction enabled on the camera. That feature works by strobing so that the pupil dilates and less light goes into the eye so less red-eye...

angevin1 · January 6, 2011

olafurdanielsson wrote: »

3. Is in also possible or Nikon, or does Nikon have something else in stead?
ÓD

No. Nikon does the same if you engage red-eye reduction.

ziggy53 · January 6, 2011

Some cameras use a short flash burst to help with autofocus. It's generally more of a problem than a solution so I have that feature turned off in all of my cameras with a built-in flash.

pathfinder · January 6, 2011

I think Ziggy nailed it, it is a pulsing of the strobe to facilitate Autofocus in low light conditions.

It can be helpful in some conditions, or blow your shot for you, depending.

olafurdanielsson · January 7, 2011

Hi again, and thanks for the replies

I used google, and found this:

Red Eye Reduction System;
Canon 550D: Small series of flashes fired by built-in flash. Flash must be raised for AF assist
Nikon D90: Beam from lamp: Approx. range 0.5-3 m/1 ft. 8 in.-9 ft. 10 in.)

it is on this page: http://www.digitalreview.ca/content/Canon-Rebel-T2i-EOS-550D-Compared-to-Nikon-D90.shtml

But I have also noticed that my Nikon uses this beam for autofocus assist (in low light conditions).

So the conclution is at least, that this beam is what Nikon uses in stead.

But I would quess that can affect the battery ending in Canon...

Thanks for the answers!

ÓD

olafurdanielsson · January 7, 2011

On the page mentioned above:

The Nikon D90 features an AF-assist illuminator beam which aids flash photography in dim light by projecting a pattern of light so that the camera can focus. The beam is also used for redeye reduction.

The Canon Rebel T2i / 550D uses a multiple strobe burst from the built-in flash to illuminate the subject under low light conditions and for redeye reduction. The strobe from the flash has a tendency to make subjects blink before you take the picture since the AF-assist and redeye reduction pre-flashes are so bright. The strobe may also be seen as an interference by others depending on the situation.

The built-in flash on the Rebel T2i needs to be raised in order for the low light AF-assist system to work. Under similar conditions, the flash can be left down on the Nikon D90 since the AF-assist beam operates independently.

angevin1 · January 7, 2011

pathfinder wrote: »

I think Ziggy nailed it, it is a pulsing of the strobe to facilitate Autofocus in low light conditions.

My Nikon/s will light up but do not pulse or strobe for Af.

pathfinder · January 7, 2011

It is not only some built in flashers. My 270ex, 580ex, and 580exii do it as well. The ST -E2 wireless flash controller for Canon helps AF as well also, but the beam of light is not visible. This can be useful in very dark situations.

Pop-up flash strobes on Canon

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