topic Re: Spot metering on the 7D Mark II in EOS DSLR & Mirrorless Cameras

Spot metering on the 7D Mark II

GrumpyJohn — Thu, 03 Jan 2019 04:42:13 GMT

I owned a 7D 1 for over 8 years and it recently was stolen out of my car. My insurance came good with a replacement 7D Mark II, and now I am learning the differences between the models.

One difference I've been noticing is the way spot metering behaves, it seems to be very hit and miss as to whether it gets the exposure rightor not.

Some images with EXIF data to show what I mean.

Camera Model: Canon EOS 7D Mark II
Shooting Mode: Aperture-Priority AE
Tv(Shutter Speed): 1/800
Av(Aperture Value): 4.0
Metering Mode: Evaluative Metering
Exposure Compensation: 0
ISO Speed: 100
Auto ISO Speed: OFF
Lens: Sigma 17-70mm F2.8-4 DC MACRO OS HSM | Contemporary 013
Focal Length: 41.0mm
FE lock: OFF
White Balance Mode: Auto
AF Mode: One-Shot AF
AF area select mode: Manual selection
Drive Mode: Single shooting

Camera Model: Canon EOS 7D Mark II
Shooting Mode: Aperture-Priority AE
Tv(Shutter Speed): 1/8000
Av(Aperture Value): 4.0
Metering Mode: Spot Metering
Exposure Compensation: 0
ISO Speed: 100
Auto ISO Speed: OFF
Lens: Sigma 17-70mm F2.8-4 DC MACRO OS HSM | Contemporary 013
Focal Length: 41.0mm
FE lock: OFF
White Balance Mode: Auto
AF Mode One-Shot AF
AF area select mode: Manual selection
Drive Mode Single shooting

Camera Model: Canon EOS 7D Mark II
Shooting Mode: Aperture-Priority AE
Tv(Shutter Speed): 1/400
Av(Aperture Value): 4.0
Metering Mode: Evaluative Metering
Exposure Compensation: 0
ISO Speed: 100
Auto ISO Speed: OFF
Lens: Sigma 17-70mm F2.8-4 DC MACRO OS HSM | Contemporary 013
Focal Length: 41.0mm
FE lock: OFF
White Balance Mode: Auto
AF Mode: One-Shot AF
AF area select mode: Manual selection
Drive Mode: Single shooting

Camera Mode:l Canon EOS 7D Mark II
Firmware: Firmware Version 1.1.2
Shooting Mode: Aperture-Priority AE
Tv(Shutter Speed): 1/500
Av(Aperture Value): 4.0
Metering Mode: Spot Metering
Exposure Compensation: 0
ISO Speed: 100
Auto ISO Speed: OFF
Lens; Sigma 17-70mm F2.8-4 DC MACRO OS HSM | Contemporary 013
Focal Length: 41.0mm
FE lock: OFF
White Balance Mode: Auto
AF Mode: One-Shot AF
AF area select mode: Manual selection
Drive Mode: Single shooting

Re: Spot metering on the 7D Mark II

kvbarkley — Thu, 03 Jan 2019 14:24:16 GMT

What do you expect? If you spot-meter on a light colored flower it will make it 18% grey.

Re: Spot metering on the 7D Mark II

ebiggs1 — Thu, 03 Jan 2019 14:27:57 GMT

You have too many variables to have any meaning. Not to mention spot vs evaluative.

Re: Spot metering on the 7D Mark II

GrumpyJohn — Thu, 03 Jan 2019 19:20:51 GMT

@kvbarkley wrote:
What do you expect? If you spot-meter on a light colored flower it will make it 18% grey.

Nice friendly answer, thank you.

I was more concerned about the fact that it seemed under exposed and the other shot was well exposed. I would like to know the reasoning behind this to help me make better choices in my settings.

Re: Spot metering on the 7D Mark II

kvbarkley — Thu, 03 Jan 2019 19:51:33 GMT

These are descriptions from your 7DII manual.

With the exception of the evaluative metering, which has more automagical smarts, all the rest of these will set the exposure such that the area in the exposure area will look like an 18% grey card. In spot metering, which only evaluates exposure in the 1.8% area of the viewfinder as shown above, it will set the exposure to make what is in the circle look like 18% grey. Shoot a polar bear in a snowstorm? Grey. Shoot a black cat in a coal mine? Grey. (As an experiment, use spot metering, press the shutter half-way and point at various objects. You can see the exposure vary.)

In your two images above the light colored flower in the spot zone yielded an exposure that made the flower grey. In the evaluative case, the camera took the whole image into account and yielded a correct exposure. The purple flower must have had a monochrome value close to 18% grey because the exposure of both spot and evaluative are pretty close.

Spot metering is really only for specialized uses and evaluative metering should generally be used. I would only use spot metering if I had a WhiBal (or equivalent) and wanted consistent exposures over a wide variety of lighting.

Re: Spot metering on the 7D Mark II

GrumpyJohn — Thu, 03 Jan 2019 21:04:05 GMT

Thank you, a very detailed explanation, just what I was looking for.

Re: Spot metering on the 7D Mark II

kvbarkley — Thu, 03 Jan 2019 21:24:26 GMT

And just for the record, I am sure your 7D worked exactly the same way.