Vignetting

[Roger]

Normally I shoot my panoramas with a fisheye and a large overlap between photos so no real vignetting problem.

Recently I have been using my 105mm to make higher resolution panos with more images and a lesser overlap, so vignetting is more apparent as a very slight banding in the sky.

However, what is puzzling me is that it seems to get worse as I decrease the aperture (which I need to do to get a decent DoF). That is the opposite way around to what I have always understood which is that a larger aperture leads to increased vignetting!

No lens hood or filters on the lens so nothing to do with that.

Anyone care to explain?

 

[Icarebecauseyoudo]

Here's the vignetting bible Rog...

http://toothwalker.org/optics/vignetting.html

You almost certainly have 'natural vignetting' as you will see

It's unclear why this should improve when you open the lens though


Unless you have mechanical vignetting and some scally has nicked your lens hood before you took the wide open shots?

What is the filter size on the 105mm?

Fuji of course make a lovely centre filter for a 105mm lens

Oh, by the way, the ideal solution I mentioned a few months back without a CF ....

Capture One lens correction feature - just get a bit of thin white perspex to take the readings - no need to buy the £60 kit really

 

[Roger]

Here's the vignetting bible Rog...

http://toothwalker.org/optics/vignetting.html

You almost certainly have 'natural vignetting' as you will see

It's unclear why this should improve when you open the lens though


Unless you have mechanical vignetting and some scally has nicked your lens hood before you took the wide open shots?

What is the filter size on the 105mm?

Fuji of course make a lovely centre filter for a 105mm lens

Oh, by the way, the ideal solution I mentioned a few months back without a CF ....

Capture One lens correction feature - just get a bit of thin white perspex to take the readings - no need to buy the £60 kit really

No filter on the lens although the size is 58mm.

PTGui lets me do a vignetting correction curve so its not that I cannot fix it, just I expected it to get better not worse with the stopping down.