Understanding particular exposure

Just wondering why this picture came out underexposed so that I can better meter in the future.

Camera was set to Manual mode. 1/100th @ F4.0, Auto ISO, Evaluative metering. Some shots came out okay, but others were very underexposed like this one. Very hit and miss on the metering compared to my t2i which is always bang on! Not going to jump to any conclusions and I will have to test this more, but looking for some opinions.

Why did the meter underexpose this? I don't see a whole bunch of white in the scene to trick the meter... there is some white napkins and some books, but overall the scene seems pretty neutral. Is it the big grey table that is causing it?

Was the lighting from flourescent lights. If so, it could be caused cycling of the lights.

Hmm.... It probably was flourescent. Didn't even know that could happen but it seems a likely cause as I've just snapped off some pictures to test the metering at home and it seems bang on.

My guess is that the camera metered off the grey table.
That's not far off being 18% grey and it looks pretty well exposed hence the rest of the shot appears under exposed.

Just curious - how does the 60D handle the Auto ISO setting when shooting in manual? I remember reading in my T1i manual that if you shoot in M mode and leave Auto ISO set, it will always default to ISO 400.

If the camera was in manual the meter doesn't do anything other than recommend exposure to you in the viewfinder. You have set the exposure yourself

Obviously the lighting has changed slightly. If you look at the histogram it is way to the left. The previous posters explanation of the light cycling could be the explanation

Riveredger wrote in post #11458257
Just curious - how does the 60D handle the Auto ISO setting when shooting in manual? I remember reading in my T1i manual that if you shoot in M mode and leave Auto ISO set, it will always default to ISO 400.

My 7D handles it great, the T1i's auto iso... I never understood why it was always just 400...

Anyways, I presume the 60D and T2i do it just as well as the 7D.

I often use the auto ISO on my 7 and 1D. Set the exposure to manual and you have effectively a shutter and aperture priority system. Its great for my kids football

Hardcore wrote in post #11457963
Hmm.... It probably was flourescent. Didn't even know that could happen but it seems a likely cause as I've just snapped off some pictures to test the metering at home and it seems bang on.

If you are photographing something which is lit by fluorescent lights that operate at the power line frequency (60Hz in the U.S.), you CANNOT use any shutter speed faster than half the time for one power line cycle.

In the U.S., this means that the fastest shutter speed you can use is 1/120 second and get reliable exposures or colors. In fact, there are very few shutter speeds that will give you proper exposure and color. Those would be 1/120, 1/60, 1/30, 1/15, and so forth. Any other shutter speeds outside of this series will capture light during uneven portions of the power line cycle and that could easily give you poor exposures and/or bad color.

Thanks for the replies. It looks like a fluorescent problem then. Thanks for all the posts! I will definitely try that next time as my photos were hit and miss. Some were good, other were underexposed with the same settings, same lighting just slightly different angles/backgrounds.

What metering mode were you using, if spot metering for instance, and that happened to be over something white then that could be a cause of the error.

Evaluative metering.

I would defintely be using a flash.

+1, use a flash.

Thanks for the comments on the flash, but that wasn't the issue. I have a flash, but I didn't want to use it mainly for the fact that I didn't want to look like the paparazzi at my kid's library program. Onboard flash just doesn't cast very flattering light imo.