So I've put the zeiss zf 35mm on the chinese made cheapo adpater and have not started proper testing yet for infinity focus, flatness, edge sharpness etc but though I'd do some quick wall shots to check the vignetting properties of this lens and show them here...
the lens cap is off..the lens is focussed on the wall about 1 meter away (closest focus is 30cm) and each shot progressively changes aperture....
oh dear..my image upload is not turned on yet..hopefully tomorrow..but in the meantime...
very bad vignetting at 2 and 2.8, bad at 4, fixable at 5.6, gone at F8...Is this amount of vignetting normal..does this make the lens unusbale at this distance?..I am sure I don't remember it this bad on other lenses...
I will test further focus distances tomorrow.
Sounds bad to me for a 35mm lens stopped down that much BUT it could also be influenced by your very close focusing distance. Curious what you see at much longer distances.
Tariq Gibran wrote:
Sounds bad to me for a 35mm lens stopped down that much BUT it could also be influenced by your very close focusing distance. Curious what you see at much longer distances.
I was think that vignetting will get worse when focus further away. Wouldn't I get a bigger image circle when focusing closer?
So I have done more vignette testing this morning with the zf 35mm.
In many real life situations it is fine..I think it it more in the shots with wide one colour spaces that we see the vignetting problem rear its head..as is normal..but of course shooting lots of images with big blue skies this may be a problem!!
I will test against a canon zoom at 35mm tomorrow but in the meantime..now that my image upload is turned on..I'd though I'd post a few samples taken purely for vignetting testing.
This looks pretty normal to me. All the wide aperture wideangle primes I have behave like this. Think about it this way:
one is lucky to get f2 at all
vignetting has never been easier to deal with because of latitude and photoshop
many shots look good with vignetting so it's not always necessary to remove it
Cinstance, you get a wider angle the closer you go, except it is an IF lens. ie you need to know this when using wides on a 4x5 camera, like Lotus mentioned
So some more testing here on the 35mm zf..i hope these images are usefull..looks quite nice to me.
Difficult to judge on their own but still...
All shots are on tripod with shutter release and mirror up at F8 and around 250th of a second shutter speed and images resized in photoshop up to 50mb which is what I have to do with my dslr images.
processed in C1 with soft look sharpening and then my minimal (getty standard) unsharp mask in PS.
centre area:
Edited by marcwilson on Jan 31, 2007 at 11:45 PM GMT
got sent this by the german person whom I bought my 35mm from..they spoke to zeiss about the vignetting..which I now see as normal..and were sent along with an explanation the following chart which basically shows the effects of vignetting on full frmae sensor and film..hard to work out but it seems to make sense somewhere!..by the way..the zeiss response came within two hours of the question..not bad!
marcwilson wrote:
got sent this by the german person whom I bought my 35mm from..they spoke to zeiss about the vignetting..which I now see as normal..and were sent along with an explanation the following chart which basically shows the effects of vignetting on full frmae sensor and film..hard to work out but it seems to make sense somewhere!..by the way..the zeiss response came within two hours of the question..not bad!
So there is indeed a light fall-off issue with current digital sensors.
from the man at zeiss..translated from the german by google..
"...In this case is in addition, a problem of the Full format sensor that Digital camera. The following diagram illustrates, how much Shading the sensor above all full opening still adds - in the corner approx. 1,5 screen stages. Up Film sees those Brightness distribution more favorably.."
