Has anyone experienced an exposure problem with the XL1s? I find it a great camera, but on manual, with no camera movement and constant unchanging lighting, the exposure seems to occasionally go down, then back up again. It's not a fantastic change and only lasts a second, but it's enough to cause the shot to be completely ruined. Any advice or suggestions would be appreciated.

Do you have image stabilization on or off when it happens?

Dittos on the OIS needing to be off. Make sure you are in M manual mode as some of the other modes may make adjustments to shutter and iris.

The stabilisation is left off and the camera is in M mode. It happens most noticeably in moderate light, where the f is at 1.6, but the camera never moves and the lighting never changes. I do actually recall reading a post a year ago regarding this problem, but unfortunately can't remember the exact details and can't find it when searching.

If you aren't zooming or focusing and it is a static shot then your camera has a problem. The problem is trouble shooting an intermittent problem like that. The service technician has to pretty much be watching the camera when it happens.

I would talk to Canon and see what they advise on getting your camera serviced. They may have encountered this problem before and advise you to send it in.

I contacted Canon about three months ago, and in two 'phone conversations they said it must be something I'm doing wrong as the camera doesn't exhibit any faults like that! I have it captured on film, so I'll probably do them a couple of clips and they can take it from there. Trouble is, every time I send a Canon camera to Canon with a fault, they always say it's perfect, regardless of the evidence I give them! Oh, well....

CJ,

Are you experiencing these problems when using a particular type of adapter or started having these problems after using one?

Gareth

Yes/no on zooming. You can have that kind of a problem when zooming with the iris wide open.

Actually, your suggestions are greatly appreciated...

The camera is placed on a tripod and the autostabilisation is off. There is no zooming or camera movement - it just points forward.
The shot is set inside in fixed lighting conditions, just perhaps a guy at a desk talking on the 'phone - then occasionally for no apparent reason the light flickers down and up for a second.

JUST A THOUGHT... I've just checked the camera and my understanding of Manual mode is that you have total creative freedom of exposure, et al. However, the exposure bar in the viewfinder will go up and down when the guy moves slightly (this would suggest the exposure is still on auto?)

So, as an experiment, I set it to AV and locked the exposure - and hey presto, the exposure bar goes up and down with slight movement! Am I doing something wrong, or is AV mode with exposure locked supposed to actually lock the exposure (allowing fine adjustment by hand)????

AV mode is not manual. It's Aperture Value (what the rest of the camera world calls Aperture Priority). M is manual. In AV you set the aperture or lens opening and the camera actively adjusts the shutter speed (brightening and darkening the picture in the process) as the scene changes.

(AV mode is not manual. It's Aperture Value (what the rest of the camera world calls Aperture Priority). M is manual. In AV you set the aperture or lens opening and the camera actively adjusts the shutter speed (brightening and darkening the picture in the process) as the scene changes)

Okay, I think I understand that my experiment with AV was less than useful... however, as my problem was when I was in Manual, isn't the shutter speed and aperture both supposed to be controlled manually when in manual? Aren't they both supposed to be fixed in Manual?

I'm sorry to ask what is probably a stupid question, but the instruction book is less than helpful and I'm trying to look for a way of stopping sudden dips in darkness for no apparent reason by locking exposure and shutter speed... I really would like to avoid sending it to Canon if I can.

Yes, if the camera is in Manual both aperture and shutter speed are locked. Exceptions are zooming the lens while in manual. The lens is a variable aperture lens and when zoomed will change the aperture in some circumstances i.e. aperture wide open at F1.6 etc. IS may also cause slight exposure fluctuations.

How are you powering your camera during your experiments, batteries or house current?

That's a very good point! I used mainly batteries, but it was only really noticeable when it was on house mains via the Canon power adapter/charger. Can electrical surges cause dips in exposure when plugged into the mains?

It could be the power supply having problems. Living in the US I can't really comment on 240v systems, but I've seen odd occurrence on 120v. Try duplicating your problems with battery power and all M settings.

C.J., have you made sure that you put your GAIN mode switch to "0"? If you leave it on the "A" setting, it will adjust for any light changes....even in "MANUAL" mode.

Hi Andrew. Yep, it's set to 0, as I don't like the noise that comes from using gain.

I was thinking... is it an exposure meter in the top left of the screen that shows itself in manual, and if so, can this affect any of the fixed setting in this mode?

C J,

I was thinking the same as Jeff. If you are running off of the AC adaptor, any brief voltage sags from someone switching on a heavy load somewhere, could cause this.

As Jeff said, try running on battery power and see if the problem still shows up. The key to this is that you mentioned the brightness 'dips' momentarily which would suggest a brief loss of voltage to the camera. Had you stated you were getting intermittent 'brightness up' events, I would be more suspect of the camera.

Anyway, the battery vs. ac adaptor test will hopefully yield an answerr. Even if you see no difference, don't rule out this possibility because it could have been something that was occuring on that day only (ie construction, a coffee pot heating element cycling on/off, etc.)

If you do see the problem using the ac adaptor, look for anything on the same circuit that would initially draw a heavy current load such as a motor or high wattage light bulb.

Hope this helps.