Canon 20D + 580EX + auto = not so auto?

[10kman]

I'll try to keep this quick to avoid eye strain and confusion....

Yesterday I was at a Christening, and my girlfriend asked me to bring along my camera. Great I thought, a chance to actually test out my new flash (sorta new anyway).

I had messed with it before, but not a ton, so it was still in "learning mode" for me.

First thing I tried was the auto mode, so I put the camera into "P", had the flash set on ETTL (auto), and according to the manual, this should be as easy as taking non-flash photographs.

Not so. Pictures were way too dark. After playing with the FEC on the flash itself, it seems that I need to get it to +2 to get the shots close to perfect. Luckily I found this out without taking any "real" shots.

I never shoot in the P or Auto modes, or even the scene modes either, I'm almost always in Av, so I figured, better try it out and get it straightened out. Put the camera into Av, set the aperture to f/8, and with the flash still on auto, the camera was telling me that the shutter speed should be over 1 second. I thought maybe it would expose properly when the shutter button was pressed halfway, still no deal. It's like it had no idea I wanted to use the flash for the primary source of light. It did flash, but the shutter was way too long.

I put the flash into M so I could adjust the power manually, the camera kept my f/8, and threw the shutter speed to 1/250, my max sync speed on this camera, just by switching to M on the flash unit.

I then played with the power of the flash and it seemed that by going to about 1/4 power, shots were okay most of the time, but I had to play with it often.

The only setup I have to compare to is the one we use around my office, which is an old Nikon D1 with a Speedlight SB28 flash. Auto on that works great for me, when I adjust aperture, it adjusts flash output (seems to anyway) and shots are usually pretty good.

When I have my Canon in Av mode, and I set the stop to f/8, should it not adjust the shutter speed based on the amount of light that can be produced from the flash?

I read the manual over and over prior and was testing in my apartment briefly off and on, but hadn't really gotten into the "field" to actually find out the quirks.

If it matters, camera was in Eval metering, ISO 400, lens was 17-40 f/4L.

I am reading through bookmarks that I had saved about mastering the EX series flashes, and am trying to find my answer.

Sorry for the long spew of words, I really did try to cut it down! The main issue was the auto not being auto, because when I gave the camera to my girlfriend for a few shots, I couldn't just tell her to put it on auto and go to town, I had to fiddle with it and hope the shots turned out okay. She's a point and shoot person, so I have to actually have the option to go to auto here and there.

Thanks in advance,

10k

ps - thank goodness for digital right now!!

edit - was using an Omni-Bounce diffuser the entire time too, wasn't trying to bounce-flash just yet. Seems to need full power on the flash when you point it up, and didn't want another variable for the day.

[Photo-John]

My experience with Canon flash metering has been so-so. I haven't used the new 580 or ETTL 2. I've heard it's better than ETTL. But your experience sounds pretty similar to mine. I'm used to doing a lot of tuning and Photoshop adusting after the fact. I usually shoot a test shot and adjust my exposure compensation before I shoot the shot that I want. This makes it hard in party situations where you really don't want or have time for finetuning. So that's where I'm used to doing Photoshop work to fix less than adequate flash exposure.

And I think it's interesting and good that you mentioned the Nikon flash metering. Flash metering is one of the areas where I think a lot of photographers agree Nikon is better than Canon. And it's been that way for a long, long time.

[EOSThree]

I stumbled on this about 2 years ago. Canon has a very frustrating flash system. I find myself reading this info a couple of times a year to try to re-understand it.
http://photonotes.org/articles/eos-flash/

[10kman]

EOS - I actually stumbled upon that a while ago too, it's in my favorites!! I have read over it about three times since Saturday, I think trial and error is going to help me best in this situation.

I actually did break down and call Canon, and got through to a tech support person.

I gave them the story above in dribs and drabs, they had this to say -

In P or Auto mode, you don't need to touch the FEC on the flash. He claimed that they have a test camera right there that is always set on P and it rarely messes up.

I told him he must have one of the few in the world, because almost every single review I have read, article too, mentions the underexposure issue, and how you need to FEC by about + 2/3. It wasn't a hostile conversation at all, we were just chatting really. He said that I can send in the unit, but I told him I'm convinced it's just a case of the user needing to learn how the flash responds in different situations.

I then asked what was up with the Av mode, and how it sets a shutter speed of over a second, even though it has the flash on the unit.

He confirmed what I have read 100 times over about how it flashes based on the foreground's distance, and sets the shutter to lighten up the background. Huh I said? That seems like a silly algorithm. He said that it should flash twice and right before it shoots, it will adjust the shutter speed accordingly. I told him no deal, it leaves the shutter open for the 1+ seconds, which would be fine if I was on a tripod, but while handheld, no dice. If any of the units responded that way, I think there'd be less confusion posts on the net about it (mine wouldn't be here for sure). I think there was a mixup of info there.

He suggested turning on Custom Function 3 on the camera, about locking the shutter to 1/250 while in Av mode with a flash. I have been shooting in my apartment with that setting, and it will still find a flash value that underexposes, about the same as if you put it in auto mode actually. So, either FEC, or just use manual with that setting, but having the 1/250 is nice.

Sounds like you need to just use Auto with the units, unless you are outside, in which case I believe it will produce better results, since you are *generally* fill flashing. The units seem to want to do that, rather than use the flash as the primary source of light.

I'd personally like a rewrite of that algorithm, it isn't accurate with what you'd think it should do. You have to reteach yourself how to use the equipment pretty much.

The Nikon system in my office is really a hand-me-down that we use for goofy things around my department, but I swear, as much as I love my Canon equipment, the Nikon never messes up, and it's an old D1. Not a bash of Canon in any way, that's not the intention of the post, it's just that the algorithms used by the ETTL can't be right.

Back to testing some more and getting this down.....

10k

[JohnMichael]

I own the Canon Eos 10D and I to have flash problems. I have used both a Canon flash and Sigma 500 DG ST. The results are inconsistent. I recently purchased a Sunpak 544 Auto and I set the 10D on manual and use the auto system of the flash. Images are much better exposed and consistent. If needed I find it easier to adjust the aperture then the exposure compensation. Of course for me this is the way I used to work so it is familiar.

[SmartWombat]

The Canon 20D definitely prefers to use fill flash and not primary flash light source.

I have taken to using Manual mode and letting the ETTL II sort the exposure, by having manual shutter and aperture I then drive the flash to expose as the primary light source.
I also use 1/500 and FP mode on the flash, so I can get better portrait shots of racing drivers without their head movement messing it up.

I used to use the 250/sec in AV mode setting too, but it was too slow to get good shots.

With the 1D you have the natural daylight exposure and the flash exposure together on two separate bar meters, so its possible to assess the balance of the shutter/aperture setting and the flash exposure at a glance.

[hesaias]

I have been using my 580EX for about a month now, and have experienced no problems. I shoot in Manual mode always. Set the F-stop for my subject, and adust the speed based on a test shot or two. I have not used an omni-bounce, but do bounce the flash by tilt and pan.

Have you tried setting the camera to manual and using ETTL?

[JSPhoto]

set the camera to manual, set the 580EX to fill flash and it should work in any light conditions on any ETTL II capable body. You can set the shutter about anywhere from slowest to 500 and get good results. It's just your preference as to the shutter speed. Your ISO will work about anywhere. from 400 to 1600.

JS

[gryphonslair99]

10kman
When shooting in AV and TV modes, Canon flashes work as a fill flash. Did you try the camera in Manual mode? F8, ISO200 with the flash in Auto mode. Give that a try as the flash will then adjust to the camera setting. Also were you using bounce mode or direct flash?