I'm an EOS 30 owner with a Speedlight 420EX. With the flash...I find that there is a lot of flash fall off (or vigneting) on the edges of my pictures (when flash not used in bouncing manner). The center of the images are very nicely toned but as you move to the sides, the tones become warmer and warmer. I can easily say that there is a difference of one stop between center and sides of the pictures. How can I remedy this problem? Another problem (by example): I went to my nephews Judo belt graduation and took pictures using the same flash/camera outfit. The kids were all dressed with white judo outfits and the decor was rather pale with high gynasium type ceilings. The resulting pictures were totally displeasing. They were underexposed and dull. There was a black boy in the class and his facial features were barely noticable. I didn't use any flash compensation because I thought the camera's metering system would be accurate. In such a situation, how much flash compensation should be used to get proper flesh tones and nice looking whites on the suits as well as proper ambient linghting (if possible)?

-- Ian Brazeau (ibrazeau@hotmail.com), May 29, 2001

Answers

All camera meters are calibrated to expose for an average tonality of medium gray. If you notice your subjects are very light or very dark, you must use some exposure and/or flash compensation. For example, I add 1 to 2 stops of light to predominantly white images and subtract 1 to 2 stops for predominantly black images.

With this said, there may be other variables. Did you shoot chromes or negs? With chromes you get exactly what you shot, so you know for sure if your exposure was off. Prints made from negs are at the mercy of the photofinisher, so you need to examine the negs directly to see if they are too thin. However, you can be several stops off with negs and still get a good print if your printer is on the ball.

I also have the same rig as you and I have noticed slight underexposure problems with the flash in certain situations. Specifically, in slow sync mode (AV, TV) it balances ambient light and flash too evenly for my taste. I merely add half to one stop of flash compensation.

Aloha

-- Puppy Face (doggieface@aol.com), May 29, 2001.

Thanks for the help!!! Well appreciated.

Letting you know that I basically always shoot in negatice format and for the cases previously mentioned, I used 35 zone metering in AV mode syncronized at 125 (mainly). Perhaps I should try using Center Weighted metering on the focusing point and flash compensating 1 or 2 stops from there!!! Any other suggestions are welcome.

Thanks,

Ian

-- Ian Brazeau (ibrazeau@hotmail.com), May 29, 2001.

Don't forget the print variability factor. I've been getting some really rotten results over the past year at a place where I normally get spectacular results. Their management must have changed or something. Anyway, I re-send the same negatives out to the same print house until they get the faces back to the color they should be. I've consulted with several photographers who have analyzed my negatives and they agree that it's processing.

Processing via high output machines uses some kind of four point exposure system. If the outer boundaries are dark (four corners), the print process is adjusted to compensate, hence, ghost white faces at the center of the photo.

It probably isn't your flash or metering combo, but more likely the processing variation. In the case of the earlier reply before mine, the exposure compensation could be working because the processor is consistently doing something wrong. That's the difficulty with prints. You don't always get what you want.

Take a photo of something fairly simple, but with a few distinct colors and have re-prints made at different places. This will cost you a couple of bucks and some time, but you'll see the variation in processing in both color and contrast. It's disgusting.

I shoot prints 99% of the time and it just bugs the you know what out of me that I pay a fortune for a camera that has +/- 1/3 EV compensation but processing variation is more like +/- 2EV!

-- Susan Butler (sue@butler22.com), May 29, 2001.

Don't forget the print variability factor. I've been getting some really rotten results over the past year at a place where I normally get spectacular results. Their management must have changed or something. Anyway, I re-send the same negatives out to the same print house until they get the faces back to the color they should be. I've consulted with several photographers who have analyzed my negatives and they agree that it's processing. Good luck!

Processing via high output machines uses some kind of four point exposure system. If the outer boundaries are dark (four corners), the print process is adjusted to compensate, hence, ghost white faces at the center of the photo.

It probably isn't your flash or metering combo, but more likely the processing variation. In the case of the earlier reply before mine, the exposure compensation could be working because the processor is consistently doing something wrong. That's the difficulty with prints. You don't always get what you want.

Take a photo of something fairly simple, but with a few distinct colors and have re-prints made at different places. This will cost you a couple of bucks and some time, but you'll see the variation in processing in both color and contrast. It's disgusting.

I shoot prints 99% of the time and it just bugs the you know what out of me that I pay a fortune for a camera that has +/- 1/3 EV compensation but processing variation is more like +/- 2EV!

-- Susan Butler (sue@butler22.com), May 29, 2001.

"In the case of the earlier reply before mine, the exposure compensation could be working because the processor is consistently doing something wrong. That's the difficulty with prints. You don't always get what you want. "

This absolutely not the case. I am exclusively a slide shooter so I don't have to worry about photofinisher interpretation of my images (they often have no clue about color or tonality). I scan the best images in a Nikon film scanner and reference the original colors of the slide when I work in PhotoShop (this is impossible with negs).

Any meter or flash will give you dark images if you shoot white uniforms in a white room. The meter is designed to average everything to medium tonality. Give it white, it sees medium gray. Give it black, it sees medium gray. Give it equal amounts of light and dark--most pictures--it sees medium gray. Exposure compensation and/or flash compensation is used to correct the meter in these special situations--too much light or dark--not because the photofinisher is screwing up. Unfortunately, exposure compensation with negs are often a waste of time because the photofinisher's autoexposure, like your meter, tries to average the neg to a medium tonality.

Try a test roll of slides. If the exposures look fine on the light table, your rig is ok and you may blame the photofinisher.

-- Puppy Face (doggieface@aol.com), May 30, 2001.

To avoid flash fall off one cheap solution is to try a diffuser - I use a Sto-Fen omni bounce. It's a small plastic cap that is available to fit a 420, that diffuses flash light giving it a good angle coverage.

-- Miguel Pais (fdespais@netcabo.pt), September 26, 2001.