50 1.8 & 550EX

[DReb-MO]

I was trying to use my "nifty fifty" and 550EX last night to take pics of the trick-r-treaters and ran into a problem. I had the 550EX set to auto and ETTL and got nothing but SLOW shutter speeds at 1.8. I tried and number of differing stops and generally got the same result each time. When I couldn't figure out what was going on I changed to the 28-135 IS lens and it worked fine. Did I miss something with the 50? Thanks.

[daveh]

Yes, don't use auto modes in the dark if you want fast shutter speeds and small apertures. In auto modes the 550 does it's best to balance the flash with the ambient lighting.

[Reminisce]

Yes, don't use auto modes in the dark if you want fast shutter speeds and small apertures. In auto modes the 550 does it's best to balance the flash with the ambient lighting.

What he said. If using the flash, shoot in one of the creative modes, preferably M, or Tv myself.

[scottbergerphoto]

The camera tries to meter for the ambient light as if there was no flash. In P mode, Canon cameras have a limit of 1/60 sec. In Av, and M, there is no such limit. The camera will slow the shutter speed to capture the available light. The 10D has a CFn. that allows you to set a minimum floor of 1/200 in Av mode. This has nothing to do with lens choice other then faster lenses can open up more and give you faster shutter speeds in low light.
Scott

[Headcase650]

I was in the same situation last night. Did some playing around, Set the camera to manual, shutter to 250/second, 550ex on high speed sync, ISO 400, then adjusted the apiture till I got a fair looking pic and histogram.

[DReb-MO]

I was using creative modes and not any of the auto modes. If I recall I tried both Av and Tv. All I did was switch lens's and the combination worked fine with the second lens, the 28-135 IS. Anyway, thanks again.

[daveh]

I was using creative modes and not any of the auto modes. If I recall I tried both Av and Tv.

Those are auto modes. Try "M".

[DReb-MO]

Those are auto modes. Try "M".

? :?: ?

The Creative Modes are Auto? That's a new one to me. I suppose I will have to use "M" with this lens and see what happens. As I went back through my notes and this forum I realized that the "nifty fifty" is one of the lenses in the EF lineup which don’t have distance data and therefore does not communicate with the flash.

Too much information to remember...

[daveh]

The Creative Modes are Auto?

That's kind of a trick question because I believe "M" is also labeled a "creative mode". So there are automatic and manual creative modes.

The way cameras get more and more automated, someday giving the user a choice of where to point the camera and when to fire the shutter will be called a "creative mode" ;)

But yes, "M" stands for manual, and the things that are not manual are automatic. Some have more degrees of automation and less user input than others.

Distance info shouldn't be an issue in a case like this.