420EX and 580EX on 20D - recommendations?

[mwillems]

Have just bought another flash. Complicated stuff - first test shots for
comparison here:

http://www.mvw.net/gallery/flash-test.jpg

Any comments? I wonder in particular why some of the pictures are underexposed even though I had no flash or exposure compensation dialled in: isn't that what E-TTL: II is supposed to prevent?

I can see this will take me a while to master - and I can see ideally I need THREE flashes,. IN the absence of budget for that, thogh, what are your recommendations?

Michael

[robertwgross]

First of all, you may have discovered that the flash metering system in the camera can get fooled somewhat when there are major portions of white in the scene. Wedding photographers run into this all the time with a white wedding gown. The human has the ability to guess when this is due to happen, and then use exposure compensation or else flash exposure compensation. You have already discovered that you can get completely different results from one camera mode to the other.

I assume that you have already read the Sticky. It covers Canon EOS flash photography in great detail.

---Bob Gross---

[mwillems]

Bob,

Indeed. I am very conversant indeed with the metering system without flash = it's the differences when using flash that surprise me. And yes, I;ve been following those links...!

Michael

[OceanRider]

I also am having problem figuring out my 580EX. I am getting wild results, blow outs, too dark, weird stuff with the Stofen Omnibounce (head on its great, 45 up and it blows out the pic) Form reading the manuals, it lead me to believe that once my 580 was on, all would right with the world and excluding whites and darks, the camera and flash would do a good job on their own in exposing the pic.....wrong!

I need to read a good book any ideas? The manuals have not helped.

Joel

[Todd Jacobsen]

I also am having problem figuring out my 580EX. I am getting wild results, blow outs, too dark, weird stuff with the Stofen Omnibounce (head on its great, 45 up and it blows out the pic) Form reading the manuals, it lead me to believe that once my 580 was on, all would right with the world and excluding whites and darks, the camera and flash would do a good job on their own in exposing the pic.....wrong!

I need to read a good book any ideas? The manuals have not helped.

Joel


Bob mentions excellent points.

Another method is for the photographer to notice contrast in the "scene" prior to the shot. But since we are digital, one can say notice histogram post shot...

The style of metering utilized (Evaluative, Partial, or center weighted) can have dramatic effect and can adjust lighting more appropriate to the surrounding contrast. It can also cause blown highlights.

Moving your subject farther away from the backdrop will help reduce the "darkening" due to the background's impact on subject lighting. It is possible that your background is actually being metered as part of your subject (vs actual background).