Canon 90D with Sigma 70-200 overexposes all pictures taken through the viewfinder (live view ok!)

[philippelang]

Hi,

I'm the happy owner of a Canon 90D. I have just bought a Sigma 70-200 lense, and I noticed that all pictures taken through the viewfinder are overexposed, no matter what I do. If I want to have a picture that is close to reality, I have to compensate the exposition with -2/-3. Tha't's a lot, not just "fine-tuning". With the other lenses, I never had this problem: Sigma 18-35mm f1.8, Canon 50mm f1.8...

Is that Sigma firmware problem? 90D firmware problem?

[ebiggs1]

" In my experience cameras are backward compatible with lenses in the same classification."

This is not true. I don't know where you may have heard or read it but there are lots of older lenses that simply will not work on a newer model Canon camera. Not that it is your issue but remember Canon doesn't and they won't make sure their cameras, 90D, 1DX Mk III, or any other, are 100% reliable with off  brand lenses. That is strictly on the lens manufacturers.

My simple test will tell you. After testing you need to decide which direction to go.

[philippelang]

Hi,

I initiated this thread a long time ago. There is definitely a problem on the Sigma side and *some* 90D bodies. I have two models, and only one is affected by this "double ISO in viewfinder mode". I sent it to Sigma along with my 18-35 Art, and after a few round-trips, it came back ok. Funny though: it has a "half ISO" problem on my other body, so basically I use this body only with this lens now, and a Canon 100mm macro lens. I use the other one with my 70-200 f2.8 and 500 f/4, it works perfectly.

This problem happened after the latest firmware update that solved problems on the 90D and 1DX, but only on some bodies. So most likely there has been a change in the manufacturing at some point, and only Canon is aware of that. I read a post of a photographer saying he started having these problem after a shutter replacement. Not confirmed, but sounds reasonable.

[cn4873]

Thanks! for the input. I know I have a lot to learn but I feel comfortable enough to take a picture of a bird and see that something is wrong. Last night I was checking to make sure all my firmware was updated. And it was like I thought. So I then proceeded to clear any custom settings on both the camera and the lens. I had planned on getting out and getting some test shots by the weather said no. I did notice that while I was playing with the focus inside the house that the camera would behave like it was in spot metering even in the other metering modes. It always seemed to lock on to my focus point and adjust exposure based on that spot. I could move my target by just and inch an see the change. That would make sense for me taken a shot of a dark colored bird and have it over expose the shot. I'm also having trouble with focus. But I'm waiting on some targets so I can run through a calibration with Focal. I'll get it figured out in time I just need a good day of shooting to lock it all in. This weekend I’ll be installing a radio on a bus for a local church so it will cut into some of my time to go out and take some pictures but I’ll do my best and let you all know how it goes.

Thanks

Rich

[cn4873]

Thank you! I'll keep that in mind.

[Waddizzle]

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@cn4873 wrote:

Thanks! for the input. I know I have a lot to learn but I feel comfortable enough to take a picture of a bird and see that something is wrong. Last night I was checking to make sure all my firmware was updated. And it was like I thought. So I then proceeded to clear any custom settings on both the camera and the lens. I had planned on getting out and getting some test shots by the weather said no.

I did notice that while I was playing with the focus inside the house that the camera would behave like it was in spot metering even in the other metering modes. It always seemed to lock on to my focus point and adjust exposure based on that spot. I could move my target by just and inch an see the change. That would make sense for me taken a shot of a dark colored bird and have it over expose the shot.

I'm also having trouble with focus. But I'm waiting on some targets so I can run through a calibration with Focal. I'll get it figured out in time I just need a good day of shooting to lock it all in. This weekend I’ll be installing a radio on a bus for a local church so it will cut into some of my time to go out and take some pictures but I’ll do my best and let you all know how it goes.

Thanks

Rich

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That is how Evaluative Metering mode works when you have an active and locked AF point when the shutter fires.  If you just did a reset back to factory defaults, this might have been what you were seeing.  

Spot Metering does not quite work the way many people seem to think it should.  While Evaluative Metering works far better than many people realize.

[ebiggs1]

"...Evaluative Metering works far better than many people realize."

Without doubt, sometimes the camera is smarter than you think.

[cn4873]

  I agree it's more sensitive then my other Camera. That was all I had to go off for my settings and it took me months to figure that out for birds in flight. I need to start all over from scratch. The problem is I’m not seeing as many birds. I also have an Air Show coming up and want to be ready. I guess it's time to get to work. Thanks to everyone who gave advice or just helped push me along. I'll get to work this weekend.

Thanks

Rich

[Ralph57]

I am having this problem with my 90D and Sigma 18-300. The Sigma firmware is updated. Liveview is properly exposed but on the viewfinder the AUTO ISO jumps u at least two stops. 

[cn4873]

Just wanted to let everyone know that I sent my lens in and had them update it and it took about 1 week which was much faster then I thought. I have no idea what they did but it works great now. A big thanks to everyone that jumped in with comments to help out. Now I just need to wait for the Birds to come out.

[ebiggs1]

"I sent my lens in and had them update it and it took about 1 week ..."

Sigma's CS is much better today than it used to be. Sigma, Tamron and Tokina, the big three off-brand lens makers used to be awol in the CS department. Tokina still is. Tamron also is better and Sigma is very much better. Brand-N used to be pretty bad, I don't know how good they are today but I hear they are  better too. IMHO, as always.