Diagonal Banding in DSLR

[soylentgreen]

I recently purchased a Canon EF 300 f/4 L IS for my 20D and must say I am impressed by the image quality of this lens. I have noticed however that there is some diagonal banding in the background on some of the images. They occur in the out-of-focus/ bokeh area of my images and do not continue into the sharp/ in-focus areas. Has anyone else experienced this problem? Have not noticed this problem with my EF 70-200 f/4 or EF 180 f/3.5 Macro. The banding all seem to move from the top-right corner to the bottom-left corner. I am wondering if this is a lens problem or just the image sensor limitation.

 

[fmw]

It isn't something a lens can do so the problem must be elsewhere. Since I'm not a Canon guy I don't have much else to offer other than that I know the lens you bought is a great one.

 

[Alex_B]

The lens is a great one, I actually got the same lens

As for the banding, did you apply exactly the same post-processing to those images where it occurs? does it occur in dark areas which are pulled up by the raw converter or in postprocessing?

You can enforce banding with any camera if you underexpose alot and then brighten up in post processing alot. But as far as I know this would occur more as horizontal banding with Canon.

The other possibility I heard of (never experienced this myself though), is that in rare cases the IS disturbs the sensor electronics. If you manage to produce a picture with that banding, try to reproduce it with IS switched off.

 

[soylentgreen]

Thanks ALex, I will try shooting with the IS turned off and see if that works. Since the banding does not occur in all of the pictures, I am hoping this may be the problem. I have not altered any of the images in post so that is not the case. Thanks fo rth eadvice.