Vignetting Issue with ND filter

[DHagan4755]

I have a Sony 24-105 f/4 lens. I bought an 82mm NiSi ND-Vario 1-5 stop neutral density filter for it. The filter diameter of this lens is 77, so I got a step up ring from 77-82. There shouldn't be any vignetting, right? Well... here's a quick & dirty example at 24mm.

I'm perplexed why this is happening. I'm not an expert in this area. Any ideas?

 

[Steven-iphone]

Have you taken any test shots with just the step up ring attached (no ND)?

Why did you not get a 77mm ND?

 

[Ray2]

It not uncommon. It looks pretty well defined. Hopefully f/5.6 or 25-26mm is OK. I have a couple of Panasonic zooms that barely provide room for a slim filter. I did the step-up routine for a polarizer and it got worse. A quick trip to DDG suggests your Sony is similar to my P's.

 

[DHagan4755]

Why did you not get a 77mm ND?

I was thinking if I got a 16-35 f/2.8, the filter size is 82.

 

[DHagan4755]

It not uncommon. It looks pretty well defined. Hopefully f/5.6 or 25-26mm is OK. I have a couple of Panasonic zooms that barely provide room for a slim filter. I did the step-up routine for a polarizer and it got worse. A quick trip to DDG suggests your Sony is similar to my P's.

After I posted this, I did further reading that this could be expected because of the way Sony designed the lens. It looks ok at 26mm. Further testing will be needed

 

[kenoh]

I think Sony have tried to keep the physical body of the lens as small as possible resulting in it not being very tolerant at the wide end for filters encroaching into the corners. From the sample it looks minor. It is not vignetting
so much it is like looking through a telescope so either zoom in slightly to 26mm like you said or spot remove them in post. Give it a few weeks and you will be less narked by it.