problem w/550EX flash on D30

For a few months I used a 380EX flash with the second-hand D30 I bought and thought that it was underpowered and thus led to a "flat" (some would say underexposed) look to my images. Bought a new 550EX, but the flatness persists. Once I put the image into Photoshop and hit Adjust>auto levels, however, the image perks right up to where I think it should be in the first place. The problem doesn't seem to exist in sans flash shooting. Called Canon about this and, natch, they suggested sending the camera in so they could "check" the calibration. I first thought I'd ask here if anyone has had a similar problem. Incidentally, it appears to produce the same results on auto, P, or "creative zone" settings. Help, anyone!
Floyd

Floyd,
Boy, this sound familiar. I started with the 420ex, and shot a wedding (on short notice) and captured a couple of hundred photos that were at least one or two stops underexposed. The camera/flash did fine in smaller rooms, and bounced o.k. I thought the same thing you did, not enough flash. So I have just purchased the 550EX and got it in the same morning of our next wedding. I had the same problem!

Being a little more aware of the problem (but not completly read up on the camera) I used the "Flash exposure lock" feature (the camera fires a pre-flash and sets the flash output by metering the active focus point.) The flash did much better, but not perfect.

I also tried to set the flash to manual mode and set the camera's exposure. this worked even better, although 1) it was not as convienient and 2) it dumped the full load and the recharging time was longer.

Since then, I have been using the "Flash exposure compensation" feature, which just tells the D30 to overexpose by a stop or two. This is much more convienient, and you must operate in any mode but the "green box" HINT: pressing the info button while reviewing the photo will show you a histogram, where you can get a better idea of the eposure of photos eposure.

BOTTOM LINE: Love the camera, but unhappy with the metering programs. Have a freind with a D60 with similar problems, and Canon has also told him to "send it in for a check" I don't know.

Also, my d30 looks about one stop under in green box for indoor/outdoor photos. Is this a problem with you or anyone else???

pat

hi floyd...

you didn't mention with which lens you were having this problem...

i can speak from experience...my first d-30 lens was the 28-135 IS...same problem...consistent underexposure (no matter what mode) i adjusted it for 2 stops exposure compensation and that seemed to take care of the problem (although it was still a bit erractic and unpredictable at times)

once i replaced the 28-135 with a 28-70 L the problem disappeared...

(i believe part of the confusion for me was my inexperience coupled with the annoying variable aperture of the 28-135)

anyhow...i'd be curious to know what lens you are experiencing the problem with...

bob

Hello Bob,

Sorry about getting back so late. But I did want to answer you (and others) who have been having similar exposure problems with the D30--and not just with the flash (on camera or 550). I've been using the 24-85/3.5-4.5 almost exclusively because it meets my focal length needs. Three days ago, I shot the facade of a restaurant with the sun at about 7 o'clock behind me. Then I went around the restaurant and shot that facade with the sun at 2 o'clock in front of me. The first bunch came out all underexposed by at least a stop, maybe two. The second bunch came out fine. The pix were taken within half an hour of each other. Go figure. And it doesn't matter which mode I use.

I'm understandably reluctant to program in an exposure compensation because of the unpredictability. I suppose I should do some tests with other lenses. I don't have any L's, but I do have lots of EF's to play with. Haven't taken time to do that because I got sidetracked buying both MF and AF Nikon film SLR's and lenses. Who knows where THAT will take me?

I'd appreciate any response to the exposure story.

Floyd

mrbobco,

The variable aperture is irrelevant to the flash metering anyway, unless you input your aperture to the flash manually.

I never have a problem with the flash exposure. When taking a picture, you have to either compensate it or preflash it with a grey object.

Happy shooting.

You might like to take a look at this link:

http://photonotes.org/​articles/eos-flash/

It's a very comprehesnive discussion of flash and EOS cameras.

Regards,

Thanks, Roger. I've begun wading through this extensive discussion.

Floyd

When you're in P, Av or Tv, and regardless of the metering system you have dialed in, the D30 goes into an evaluative metering pattern reading all segments and weighing the segments into three zones--with heavy bias on the center zone. You should ALWAYS use FEL (unless it's impossible, that's the way the system is designed), and you should ALWAYS push FEL pointing the center of the viewfinder on the PORTION OF THE SUBJECT YOU WANT TO MEASURE FLASH LIGHT FROM. Then recompose and press shutter. Most of the mistakes come from pressing FEL when the center sensor is aiming at the background which is typically reflecting much differenlty from the subject you want to flash expose correctly.
Assuming you're FELing correctly, using exposure compensation is as normal a process as when you meter without flash. Unless your subject is 18% reflective you NEED exposure compensation. It's not a fault of the camera, that's the way every metering systemt works. The only difference is that digital sensors don't have the latitude of film and errors in exposure will show up much faster and brighter (no punt intended).
If you do all that correctly and the flash output is still wrong, then you need camera recalibration.
By the way, a little underexposure of flash output tht you fix in PS is probably not that bad given that even a tiny bit of overexposure of people face turns totally white and not very pleasant.

Philippe
www.epochphotos.com

Look here : http://www.dlcphotogra​phy.net/CanonLetter.ht​m

Regards

Michael

Thank you, Bob. I thought it was *me* all along. The 28-135 IS is a puzzling lens, to say the least. It is my every-day lens but fools me more than half the time, with or without flash.

Philippe; Thanks for sharing your flash tips. I remembered a lot I knew and forgot in the confusion. FEL is the only way I ever trust a flash shot with the D30/420 EX combo but the background mistake is one I'm sure I did and never knew why it turned out the way it did. I'll watch that from now on thanks to you!

I have a similar problem of underexposure with my D60/420EX combination. But there is no such problem if I'm using the camera's built-in flash. If the FEL is working the way that Canon say it should, then why does it not give the same under-exposure when the built-in flash is used, I wonder. The 420EX seems to be consistently under-exposing by1.5ev compared to the built-in flash for the same scene in my case. While the problem with the 420EX could be solved by using flash exposure compensation, it is a bother when I revert to using the built-in flash as I must remember to reset the flash exposure compensation.

PSChia:

Is this an observation you've made from "controlled" experiment (i.e., same subject, same distance to subject, and same everything else) with built-in flash and with external flash--or is it empirical experience on different shots some done with built-in flash and some with external flash?
If it's from controlled experiment it would rule out your camera as needing recalibration as it's the same chip that measures flash output whether it's using built-in flash or external flash. That would suggest it's your external flash unit that "underexposes."
If it's empirical evidence from shots, my hunch would be that you may use your built-in flash in very different situations than when you use external flash (perhaps when you're closer to the subject and have less non-subject stuff in the measurement of flash output to through it off) in which case it makes sense that you encounter more issues with external flash?
I think it would be interesting to do the controlled experiment though to see if you really see exposure difference when everything is the same when you use external and built-in flash.
As far as exposure compensation, the 18% rule applies to whatever source of light you use--so that's not an issue.
I've had underexposure problems when I started using external flash (the only cases I've use built-in is for fill-in when I didn't have external flash with me), but these were because of FELing "wrong". I still once in a while forget to FEL right in the middle of the piece of the subject I want to measure flash from. From what I can tell the D30 and the 550EX work wonderfully together as long as you're maniac about reading flash output EXACTLY where you need it. It's almost as if you're doing a spot reading rather than the evaluative it's supposed to be doing--a big difference from film cameras I've used where it doesn't make that much difference if you're spot on or slightly off when you measure. And the further away from the subject you are, the more maniac you need to be. It may be the algorithm used by the camera or whatever, but once you take care of that, it's extremely reliable.
Philippe

i have to add, too philippe...you are SO right!

i have experienced the same thing...forgot to mention that in addition to the ev, FEL helped me survive...

i had a TON of shots of a lady in a black dress...what a NIGHTMARE! over/under etc...until i wised up and used FEL...

as i mentioned...once i bought a 28-70L, i was able to set my ev back to normal...even with the flash, i rarely have exposure problems...now...my damned unsteady hands : )

glad to help...

bob

My observations were from controlled experiments with the same subject, distance and exposure conditions. The external flash was consistently 1 - 1.5 stops lower than the on-camera flash.

I read from the other Canon DSLR forums that for them, this problem was resolved when they upgraded their cameras' firmware to ver. 1.0.2, but my camera came from the factory with the latest version of the firmware and I still have the same problem. Could it be a problem with the 420EX instead, I wonder.

PSChia:

If you shoot in ETTL with FEL then regardless of whether you use the built-in flash or the external flash, the camera determines the amount of light required for proper exposure and I don't understand how it could get different measures depending on whether it's the built-in flash or the external flash that's being used. As you suggest perhaps it's your external flash that does not shoot the right amount of light (for whatever reason)? Have you tried another external flash unit?
I'll try to do this experiment with my D30, with exactly same conditions shooting built-in and external flash.

Philippe