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

[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]

That sounds just like my issue. It had to be sent in for the update. I'm not sure what they do because it came back with the same FW. But they did inform me that they had a software fix for it. You can send them an email via the service ticket sight and they can let you know. Just look on the Sigma sight.

[mikeaff]

Just purchased a 90D to upgrade from my 80D and am having this exact problem with my Sigma 150-600 C.  Spoke with Sigma today and they verified everything that's already been posted about Sigma's non-user fix.  (you need to send the lens into Sigma for their in house update).  The guy I spoke with had some harsh things to say about the 90D metering, but he may just be talking Sigma's book.

The 90D seems to meter approximately the same as my 80D and 6Dii with Canon lenses, but I'm still seeing aboiut 1/2 stop overexposure with my 400mm 5.6. vs the other 2 bodies.  I'm getting about 2 stops overexpsure with the 90D and the Sigma.

I might just have a not too great copy of the 90D.

In any event, I've been really happy with the 80D, so the 90D is going back. (The Sigma 150-600 is my primary lens-birds and wildlife and I don't want to hassle with sending it in and hoping Sigma can fix my problem).  I'm just going to hang around a while longer with my 80D and 6DII, which both work perfectly with the Sigma lens, and then go mirrorless I guess.

[ebiggs1]

You might be too quick to condemn the 90D. The evaluative metering mode is the default for a 90D.   Evaluative means the camera uses certain algorithms to adjust the exposure.  This works well most of the time but it can be unpredictable with certain lenses and certain circumstances.  A BIF against a bright sky for instance. Try changing the metering mode.