Target distance glitch

[YoyoBoy]

I've had this problem here and there over the past year, but only now have I figured out what's causing it: In order to use VRay's Depth of Field, I'll animate the target distance. But sometimes I find doing that screws up the render, making the view much closer than it should be, even though everything looks fine in the viewport. Has anyone else had this issue?

Also, I don't know if this is related at all, but while trying to solve this problem I've found that animating the camera adds keyframes on the ISO track, even though I'm not touching that parameter. So I just delete those keys. Why is that happening?

Thanks.

Oh, and I am using Max 2016

[stevesideas]

I'm having exactly the same problem. What appears in the viewport does not reflect what is rendered. The target distance is causing issues here. Is anyone at Chaosgroup aware of this ?

[YoyoBoy]

This issue has raised it's ugly head again, and the renderfarm won't reimburse me since it's not their problem. I will be sending a file for you to check out shortly.

[Ihno]

I had such behavior with the max physical camera. Try to use the vray camera. The max script snippet to create one is floating around here in the forum somewhere.

[YoyoBoy]

So it's a problem with Max rather than with VRay? Would you have any idea if it's a problem with Max 2016 only? So perhaps if I tell the farm it's a Max 2018 project, it might render out properly?

[YoyoBoy]

I wonder if the "Lens Breathing" feature is what's causing the problem. Maybe I should set that to 0. Though one would think the effect of something like that would be visible in the viewport.

[Ihno]

I had those problems in 2016 two or three times and never used the max camera for animation again after that.
So I don't know if the problem is solved.
I read something about problems with the lens breathing feature.
The guy said he had random cam positions on different rendering machines.
I never had any of those issues with the vray cam. I'd copy the anim tracks over to a vray cam and never look back.
Before I went back to the vray cam I solved the issues (animated fov in my case) by linking the camera to a helper which did the cam movement and baking the inner cam parameter animations to one key per frame.
And it worked.. But I really wouldn't use the max cam for animation jobs again.