Whats wrong here? CV 21mm f/4

> motion blur

You know, that's my first feeling about it too. Refer to the stripes on the kid's pants. Sort of an odd rotational movement, maybe moving only during part of the shutter travel.

A tripod, slow film and a distant brick wall will tell the tale.

I didn't find my first roll with the CV 21 all that wonderful either, but it's not a 21 ASPH and definitely some pilot error was involved. I think mine will turn out to be a very usable lens but of course will only inspire desire for a 21 ASPH or the Zeiss 21. <g>

-jbh-
 
looks like decentering. would be worse wide open than stopped down and this might be why some are ok and others less so. I suspecta duff lens got rhu QC and the owner sold it on rather than returning it as faulty. Cant see how it can be motion blur or anything but improperly aligned elements...
 
I once had a similar problem with a jupiter; It was M mount, so I rotated the lens 90 degrees (holding them onto the camera as it did not clip and took a few shots. The same bluriness showed, but rotated; that told me it was the lens, which I had since then fixed. If you do that and it still blurs on the left, there must be something else wrong.
hope it helps.
 
I once had a Canon 50mm/1.2 lens that had similar problems. The local repairman was unable to figure it out, but DAG found the source of problem. One of the inner glass elements was not positioned correctly. Now the lens is tack sharp. Maybe your lens has a similar problem. Good luck in resolving the mystery.
 
chambrenoire said:
Only on about three negs, on a roll of 36 so it's not too bad but rather annoying when the pictures taken could have been quite good.

But if I moved the camera while taking the picture, wouldn't the whole picture be blurry?
Click to expand...

Not if you rotate the camera. Rotations happen easily due to you pushing the trigger. I am with the ones suspecting motion blur.

I suggest a couple of controlled images with a good tripod, to establish whether there is or is not a lens problem.


Anyway on 35mm cameras apertures 11 to 22 should be no go areas, unless you desperately need longer times or excessive depth of field. Diffraction is going to kill you there.
 
you need to do some methodical controlled testing, it's the only way to figure it out. Without knowing the point of focus, aperture, shutter speed...all the above is just a guess. Time for the loathesome brick wall.
 
Were the "okay" images shot at a high f/stop that would have masked the misallignment? A good contolled test would be camera or a tripod and shooting several photos as f/4, f/8 and f/16. Brick walls are okay, I guess. Buy you could also try a scene with near and far elements.
 
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