Consistent underexposure on 20D

[saggs]

Been using the 20D now for approx 2 months and I'm finding the camera is underexposing all images by default by approx 2/3 to 1 stop. Decided to experiment with 300D body, same lenses, same settings and the 300D images are much brighter (about 2/3 stop). Also, using 550ex with 20D requires +1 stop FEC compared to the 300D. Anyone else finding this? Have I got a duff copy? Okay, I know you can dial in EC but the 20d default exposure appears too dark to be correct and surely I shouldn't have to either use +1stop or meter for shadows all the time.

[tim]

Yep, it's common, use exposure compensation and your histogram to tweak it. The 20D tends to expose to preserve highlights.

[saggs]

ok thanks - guess I'll just have to get used to it.

[J Rabin]

This sounds suspicious. I've owned Canon film bodies, the 10D, and now 20D. I've never had exposures as accurate as my 20D. Even under highest contrast outdoor scenes, using Av mode or Tv mode, my histograms "drop right in" the bounds. Exposure is trick on my 20D, which I attribute alot to ease of placing the active focus point over the right "tone" in a subject. 80% of the time I use M mode anyway, and meter off something I estimade as equal to neutral gray in a scene, or joystick the focus point over someone's facial skin, especially when using flash. 1. Check your settings and active focus points. Since exposures are focus point weighted in other than M, make sure you know where your active focus point is landing. 2. Make sure you know what the camera meter is seeing by paying attention and opening images in EVU to check where the focus point landed. 3. Some lenses backfocus, and then they do, metering can be off. 3. Most of time this stuff is operator related but, if it still fails, Canon service. Hope that helps.

[Mark_48]

I got my 20D a about a month ago and as saggs noted it seems to consistently underexpose by the same amount he cited. I'm also comparing to a 300D which usually gave good exposures with no compensation in just about any mode I used.
I've read alot on this board of 20D users that seem to get good exposure without compensation and I wonder at times if Canon may have had a production run that may have been miscalibrated. I would probably as others, prefer that a good balanced exposure and histogram were at "0" and make needed adjustments from there. Has anyone had a 20D recalibrated?

I'm probably going to try a few checks with a handheld lightmeter vs. the 20D's metering to see how they compare on an 18% grey card.

[I Simonius]

This isn't quite the same thing but can anyone tell me why the AEB is set at one mark to the right of '0' ?

Thanks

[HJMinard]

Mine exposes perfectly ... definitely better and more accurate than my previous DRebel. It even handles snow (doesn't overcompensate and make my snow grey) and other bright highlights quite well ... I rarely need to use EC.

I don't agree that it's a common problem. I've read many accounts of underexposure when using the 20D with flash, but I've seen very few complaints about underexposure in general (daylight ... non-flash usage).

[HJMinard]

This isn't quite the same thing but can anyone tell me why the AEB is set at one mark to the right of '0' ?

Thanks

It shouldn't be - by default it should be zero. Must've accidentally moved it over ...

[Mr. Pickles]

The AEB is off because your camera is set to compensate when taking one picture. If the AEB's middle dash is on +1, then if you look at the single shot compensation, it is +1 also.

The 20D underexposing is a bit odd. I had a D60 that overexposed by 1 to 2 stops when I got it. I sent it in, and BAM, new camera came back fast. If you shoot a gray card, and you have to adjust the image, it would be going to the doctor since you limit your range on that one end, and that isn't good. Unless of course your adjusting it because your PC monitor is off, but I don't think that is the case.

[peter/c]

I have had 20d since last October.I used to complain about high 'noise' on My images. However, since using both histogram and EC together, to expose to the 'right', My pictures are a lot 'cleaner' Sometimes I need EC by a stop or even more, but then I shoot a similiar scene with same settings and the highlights are blown away.Therefore I use standard settings ensure I at least get the shot and if I get a second chance,i.e. a landscape then i adjust accordingly.
My 300d never coped well with Highlights either.
Peter.

[Hellashot]

My Drebel is the same way. Takes dark pictures, but every one turns out just fine after post processing/autofixes.

[I Simonius]

The AEB is off because your camera is set to compensate when taking one picture. If the AEB's middle dash is on +1, then if you look at the single shot compensation, it is +1 also.

scratching head............I am SOOOOOOO confused! :cry:

[tim]

Are you sure it's not on zero and it's just a funny scale? Sometimes the little diagrams don't line up perfectly.

[I Simonius]

It might not be the AEB - its the thing in the viewfinder that goes from -2 through 0 to +2
It s set to the first notch to the right of nought ('0')

[robertwgross]

Simon, as was stated previously, you moved it one notch and then the camera retained that as its new default.

You can set it up again to do EC, and the notch offset can be eliminated in the same manner that you had set it.

---Bob Gross---

[GMosher]

I can't say I've had this problem with my 20D. From broad daylight shots to VERY low light shots, to flash shots...I haven't run into this yet.

[I Simonius]

Simon, as was stated previously, you moved it one notch and then the camera retained that as its new default.

You can set it up again to do EC, and the notch offset can be eliminated in the same manner that you had set it.

---Bob Gross---

But I don't think I did set it!
It was always like that - I can't work out yet how to change it :oops:

[Icecamp]

Half press on shutter, turn big wheel. That's your exposure compensation.

[I Simonius]

THANKS!
Ahh I trtied that and it only seems to work in Manual otherwise it defaults back to one point to RHS of '0'

[dhbailey]

Turn the camera on with the line the farthest up it can go, where it points to the line leading over to the thumb-wheel. That allows the thumb-wheel to adjust the exposure compensation when the shutter-button is half-depressed.

You can set that by turning the camera on one notch further than you thought, and could have accidentally set the exposure compensation, which would then remain as you set it after you turned the camera off. Next time, if you turn the camera only to the ON position, you can't use the thumb wheel to adjust the exposure compensation.

[saggs]

This sounds suspicious. I've owned Canon film bodies, the 10D, and now 20D. I've never had exposures as accurate as my 20D. Even under highest contrast outdoor scenes, using Av mode or Tv mode, my histograms "drop right in" the bounds. Exposure is trick on my 20D, which I attribute alot to ease of placing the active focus point over the right "tone" in a subject. 80% of the time I use M mode anyway, and meter off something I estimade as equal to neutral gray in a scene, or joystick the focus point over someone's facial skin, especially when using flash. 1. Check your settings and active focus points. Since exposures are focus point weighted in other than M, make sure you know where your active focus point is landing. 2. Make sure you know what the camera meter is seeing by paying attention and opening images in EVU to check where the focus point landed. 3. Some lenses backfocus, and then they do, metering can be off. 3. Most of time this stuff is operator related but, if it still fails, Canon service. Hope that helps.

Thanks for this. I understand what you are saying here and by metering off a neutral grey area in a scene I achieve a better balanced exposure (ie more centred on the histogram). However, I've just tried a further experiment with both camera bodies and a 70-200F4L lens. Both cameras in evaluative metering mode, same settings throughout, same focus point, the 20D measures 1/800 at 5.6 and the 300D 1/500 at 5.6. My main concern is that the 300D provides far better exposure for quick grab shots and there should not be any diff in the meter reading. I'm having to compensate with the 20D when I feel I shouldn't have to.

[I Simonius]

DHBailey:-
BRILLIANT! Thanks, that got it!