Light falloff: FF vs film

[john_lai3]

Is light falloff (vignetting) more pronounce on FF than on film? I thought FF sensor has the same size as a

35mm film...

[ShunCheung]

There are more than just sizes. Traditional film is a flat surface. The current digital sensors have a lot of tiny "wells" called photosites to collect light. The walls on those wells will block some of the light, especially for the wells near the edge of the frame.

[ilkka_nissila]

Yes, on some superwide angle lenses there is quite severe vignetting on FX. On normal lenses and teles, I don't

think there is a significant difference although I haven't literally measured it (need to normalize the tone curve to

do this comparison and haven't bothered to do it).

 

With almost all (22) lenses that I have used on FX , I haven't found vignetting to be anything to be concerned about.

Three exceptions: 25/2.8 ZF, 105 VR AF-S, and 70-200 VR AF-S. Those lenses have quite significant falloff which

clears adequately when you stop 2, 1, and 2 stops down, respectively. I haven't used the 105 on film, but the

others seem to have similar amounts of vignetting on film, subjectively evaluated.

[elliot1]

The D3 has a vignetting control - I believe it was added with the latest firmware).

 

Many have reported issues with the 70-200mm specifically. I find the vignetting minimal and easily controllable. With the vignetting option turned on, there is virtually no vignetting. With PP, there is absolutely none.

[keith_b1]

You can add the ZF 18mm as one of the 'stronger falloff' lenses on FF (D3). Other than that, a great lens!

[john_lai3]

Okay.. Next topic.. Softness at corners with some lenses (i.e, 70-200mm VR). Is this more or less a lens' issue

or FF (vs film) can contribute to it as well?

[ilkka_nissila]

If the light from the lens hits the sensor fairly perpendicularly and if the lens has no CA, then it should behave very

similarly on film and digital. If you look at lab prints which are cropped a bit or mounted slides then you won't see much

of the problem in film images. ;-) I scanned some slides taken with the 70-200 with mounts that don't crop the image and

they're very blurry in the corners. While I owned the lens, I didn't do a direct comparison between film and the the D3

since I didn't think there was an inconsistency. My opinion is that for this lens, it's just the lens that's the problem.

Incidentally, my old 80-200/2.8 AF-D N behaves well on the D3. It has a touch of vignetting wide open but not like the 70-200. The 80-200

corner sharpness is okay, not as good as the 180/2.8 but at least they're not a

total blur. The 80-200 has a bit more CA and the bokeh isn't as nice as the 70-200's, and the lens has no VR or AF-S, but on the

other hand its a couple of hundred grams lighter and a bit shorter, so there, informed choice. :-) To be honest, I miss the

bokeh and AF-S of the 70-200 (take note, this is the first moment I express the slightest regret wrt. this topic).

 

Keith, thanks again for your data point. It looks like Zeiss is designing their lenses with traditional expectations that a

wide angle lens is usually used stopped down.

[elliot1]

John, I intend on investigating the soft corner issue as soon as I find a nice brick wall to take a picture of.