DPReview.com is closing April 10th - Find out more

[BUG] Sigma 56mm Weird Auto-ISO behavior

Started 10 months ago | Discussions thread
Morris0
Morris0 Forum Pro • Posts: 32,181
Re: [BUG] Sigma 56mm Weird Auto-ISO behavior

Hotel Lonely wrote:

It's quite strange, but the camera would automatically lock to 1/300s shutter speed, when using the Auto-ISO feature with the slowest shutter speed set to Auto.

Which is quite weird. In general, most cameras would choose a number like 1/50, 1/56 or 1/60s (when using a 56mm focal length lens).

I noticed that when using Fujifilm lenses, the behavior is as expected, which means the slowest shutter speed would be automatically chosen to a number close to (1/focal length).

It only happens on the Sigma 56mm f/1.4 at the moment. But honestly, I haven't tested other Sigma XF lenses yet so I'm not sure about other lenses.

I tested two copies of 56mm dcdn and two copies of XT4. I tried everything, when the Sigma isn't performing as expected, a lens swap to Fujifilm lens would magically choose the correct shutter speed again, without any changes on the settings.

Which means it's not about my settings, but about the lens. Even with default factory settings, the similar behaviour happens too. I also read some other similar reports about this lens and auto-iso behavior bug on the forum.

My guess is that this is a lens or camera firmware bug, is there any feasible way to let Sigma/Fujifilm know this and get it fixed ASAP?

Report the issue to Sigma.  I've given up on Fuji Auto ISO as it's way too unpredictable for me.

Morris

 Morris0's gear list:Morris0's gear list
Fujifilm X-T3 Fujifilm X-H2S Canon EF 200mm f/2.8L II USM Nikon AF-S Teleconverter TC-17E II XF 90mm +11 more
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow