Canon 50f1.4 overexposes

I just got the 50f1.4. It seems to overexpose by 1/3 stop or so. Is this common for this lens? None of my other Canon lenses do this, but I did read a report like this at the digital picture website:
http://www.the-digital-picture.com …-1.4-USM-Lens-Review.aspx
Anyone else notice this?

What do you mean?

If you set the camera to common exposure using one lens and then another, it would not be unusual for a fast prime with few elements to deliver a result that is 1/6 to 1/3 stop brighter compared to a very complicated zoom like the 70-200 or 24-105.

If you are relying on the camera meter for exposure, the difference is probably due to the different vignetting character throwing off the meter.

I have a number of other lenses, including the Canon 35f2, 85f1.8, Sigma 50f2.8 and the Canon 100f2.8 f2.8 macro. All exposures seem right on, but the 50f1.4 overexposes using the camera meter. I generally use evaluative metering and it works fine with all of my other lenses. The 50f1.4 needs to be set at -1/3 stop to produce what appears to be a good exposure.
I tried the lens out with a T2i that seems perfect.
the shot of the keys was -1/3 stop, and the other was not adjusted - it is too light in brightness.

HOSTED PHOTO
please log in to view hosted photos in full size.

HOSTED PHOTO
please log in to view hosted photos in full size.

Have you set up the 50 and a couple other lenses on a tripod and shot the exact scene (framing wise) under the exact lighting conditions in manual mode?

Here are two with similar lighting, but taken at different times. One is the Canon, the other is the Sigma macro.

HOSTED PHOTO
please log in to view hosted photos in full size.

HOSTED PHOTO
please log in to view hosted photos in full size.

Those are completely different angles. IN the first the background is totally white, thus rendering a too-dark exposure. In the second, 1/3 of the background is brown. The only way to do a fair test is to shoot in manual in a side by side test.

But to answer you question, I found my Sigma 30mm f1.4 and Canon 50mm f1.4 to expose similarly.

also you need to have about the same size of the image, if you zoom in or out more. That will give you different metering. As you last post the has different angles and different degrees of dark and light areas to meter.

what does the histogram show about your exposure. Does does it show you are over exposing?

I really don't need to do a formal test on a tripod - I can see the real objects in the room. I have photographed all of these things with other lenses - including the 50f2.8, 35f2, 18-55IS (X2), 85f1.8, 100 macro, and I can see the objects. The first thing I do when getting a new lens is check to see if focus is OK, and take lots of photos of objects around the house. The 50f1.4 produces a noticeably different, and much lighter image. If I set the camera to - 1/3, then the images look about normal. The exposures range from about OK to overexposed. I was just wondering if this is just my lens, or if it is common.
It does not take a formal test to determine exactly how much the lens is overexposing, to see that it is doing it. I can compensate by setting the camera to -1/3 stop, as long as I remember to do this when the lens is on it.
Anyone else notice this, or is it just my copy and the one at the digital picture dot com?
Do I have an f1.2 lens in the guise of an f1.4? I may do some formal tests later.

After spending 40 years in the security system installation and service business I learned early on that determining a problem was a process of elimination.

For me, to determine a lens or/and body issue requires eliminating all ambiguities. That involves dealing with one issue at a time. Is it the lens, body, flash, metering for exposure, metering for flash?

Mine seems to do the same thing. I just add a bit of exposure compensation on when shooting with the 50. I always shoot RAW, so its not a big deal anyways.

I have a hood on order, and it may help. The fast apertures may contribute to the exposures, but I also need to take some photos outside, as soon as the rain ends.

I tried the lens outside, and exposures were better. In fact, when I had the exposure compensation at - 1/3 stop, the lens underexposed by that amount.
It must be related to indoor lighting and the large front lens element. I am willing to bet that a hood will help.

I've noticed that there is something different with the exposure from the EF 50/1.4 too. At first I thought it was due to greater light falloff wide open since metering is done wide open. I thought that the darker corners would cause the meter to indicate longer exposure.

I just tried it with filling the frame on an 18% grey card, ISO 100, f/2.5 selected in Av mode, cloudy white balance and infinity focus using the EF 50/1.4. I took the pictures and compared them first with the 7D. Matrix and center weighted averaging gave the same 1/8s exposure while partial metering gave 1/10s exposure and a 1/3 stop darker image. Then I put on the EF 50mm f/2.5 CM lens on and tried it again. This time the meter indicated the same 1/8s but the resulting picture was closer to 2/3 stops darker. It wasn't due to loss of light from high magnifications as the lens was at infinity focus. Strange.

Then I tried the same test with a Rebel XT. This time the EF 50/1.4 metered 1/10 second and made the same brightness as on the 7D at 1/8s. The EF 50/2.5 metered at 1/8s, the same as on the 7D but the image was only 1/3 stop darker than the 50/1.4 and 1/3 stop brighter than on the 7D for the same settings.

Could it be related to this?:
http://www.luminous-landscape.com …amera_manufactu​rers.shtml

macroimage wrote in post #11961746
I've noticed that there is something different with the exposure from the EF 50/1.4 too. At first I thought it was due to greater light falloff wide open since metering is done wide open. I thought that the darker corners would cause the meter to indicate longer exposure.

I just tried it with filling the frame on an 18% grey card, ISO 100, f/2.5 selected in Av mode, cloudy white balance and infinity focus using the EF 50/1.4. I took the pictures and compared them first with the 7D. Matrix and center weighted averaging gave the same 1/8s exposure while partial metering gave 1/10s exposure and a 1/3 stop darker image. Then I put on the EF 50mm f/2.5 CM lens on and tried it again. This time the meter indicated the same 1/8s but the resulting picture was closer to 2/3 stops darker. It wasn't due to loss of light from high magnifications as the lens was at infinity focus. Strange.

Then I tried the same test with a Rebel XT. This time the EF 50/1.4 metered 1/10 second and made the same brightness as on the 7D at 1/8s. The EF 50/2.5 metered at 1/8s, the same as on the 7D but the image was only 1/3 stop darker than the 50/1.4 and 1/3 stop brighter than on the 7D for the same settings.

Could it be related to this?:
http://www.luminous-landscape.com …amera_manufactu​rers.shtml

I read this article a few months ago when I noticed 2 of my f2.8 lenses (TS-E90 and 100L) would expose 1/3 stop differently at 2.8 than when closed down a stop or more.

Not all lenses are the aperture they are marked, especially wide open - if you are doing some manual exposures.