n00b flash question 1/250 max shutter speed?

I have a 7d and a 580exII flash.
I was trying to shoot some portraits the other day with a 50mm f/1.8 outdoors.

I went into manual mode and put my aperture at 1.8 and my shutter speed to the max (only 1/250s). The shot was blown. I put my ISO on 100 (the lowest) and it was still blown.

What am I doing wrong? How should I have taken the shot if I want to use f/1.8 and a flash outdoors?

FunkyELF said:

I have a 7d and a 580exII flash.
I was trying to shoot some portraits the other day with a 50mm f/1.8 outdoors.

I went into manual mode and put my aperture at 1.8 and my shutter speed to the max (only 1/250s). The shot was blown. I put my ISO on 100 (the lowest) and it was still blown.

What am I doing wrong? How should I have taken the shot if I want to use f/1.8 and a flash outdoors?

Click to expand...

You need to set high speed sycnc on the flash. Then you can use any shutter speed. It's in the manual.
--
Brian Schneider

I am assuming you are referring to the background (ambient lighting) as being blown, and not the foreground flash lighting on the subject.

• You'll need to use a Neutral Density Filter to cut down on the ambient light. This of course affects the flash output too, but the ND filter affects both the flash output and the ambient light equally. You'll have to get a high xxND filter to cut the ambient light sufficiently to shoot at f/1.8

• The other option is to put your flash in High Speed Sync Mode. This will allow you to dial in shutter speeds above the camera's max sync speed of 1/250. But be aware that the range of the flash's output in HSS is greatly reduced; your flash is essentially acting like a continuous light source, and will eat your batteries. You will have to place your subject mush closer for a proper flash exposure.

• The other option if you're not too fixated on shooting at f/1.8, is of course to use a slightly narrower aperture, but still shoot at the camera's max sync speed. Your flash won't have to work nearly as hard.

Regards/ Mike

FunkyELF said:

I have a 7d and a 580exII flash.
I was trying to shoot some portraits the other day with a 50mm f/1.8 outdoors.

I went into manual mode and put my aperture at 1.8 and my shutter speed to the max (only 1/250s). The shot was blown. I put my ISO on 100 (the lowest) and it was still blown.

What am I doing wrong? How should I have taken the shot if I want to use f/1.8 and a flash outdoors?

Click to expand...

--
B.R.A.S.S. (Breathe, Relax, Aim, Sight, Squeeze)



A Link To - WilbaW's Unofficial Rebel Forum FAQ- http://snipurl.com/RebelFAQ

Watch this video. It is a Pocket Wizard ad but it has good animations. Explains what HSS is. You don't need to purchase PW to make HSS work. NOTE: The presenter will talk about a sync speed of 1/200. Most cameras are. The 7D is 1/250.

http://www.pocketwizard.com/inspirations/tutorials/pocketwizard_controltl_optimiz/

When you get comfortable with that watch this. Shows it in action. You don't need all the gear to do this.
Videos - Tutorials - Lighting Tutorial

http://www.stansphotos.com/
--
There is nothing worse than a sharp image of a fuzzy concept.

Ansel Adams

[NT]

No problem. One of my favourites as it really made it clear for me. Check this out.

http://www.youtube.com/watch?v=-isRz54C_vY

--
There is nothing worse than a sharp image of a fuzzy concept.

Ansel Adams