topic Re: Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm in EF & RF Lenses

Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm

dpisarra — Thu, 05 Aug 2021 04:07:33 GMT

I have a 35mm Art 1.4. On my Canon Rebel T3i I get perfect pictures at 1.4, and on my Canon 90D ( also a crop sensor) I get blade interference at 1.4 - Why? What am I missing here?

Re: Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm

Waddizzle — Thu, 05 Aug 2021 09:29:13 GMT

@dpisarra wrote:
I have a 35mm Art 1.4. On my Canon Rebel T3i I get perfect pictures at 1.4, and on my Canon 90D ( also a crop sensor) I get blade interference at 1.4 - Why? What am I missing here?

What exactly is "blade interference"? I have never heard that term before.

Can you post sample images that demonstrate the issue?

Re: Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm

jrhoffman75 — Thu, 05 Aug 2021 11:16:10 GMT

@dpisarra wrote:
I have a 35mm Art 1.4. On my Canon Rebel T3i I get perfect pictures at 1.4, and on my Canon 90D ( also a crop sensor) I get blade interference at 1.4 - Why? What am I missing here?

Do you mean vignetting?

Re: Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm

dpisarra — Thu, 05 Aug 2021 15:03:48 GMT

I think it's a firmware issue. Sigma has replied that they have an update to fix this known issue.

It is vignetting - oddly it shows up in the preview, but not the CR3 or DNG on Lightroom.

Thank you for participating and trying to help.

Re: Blade Interference on Canon 90D with a Sigma ART 1.4, 35mm

kvbarkley — Thu, 05 Aug 2021 15:12:46 GMT

The preview is a jpeg that is created by the camera.