Shutter or lens issue?

Fenster

Clicky

I was shooting our cats on the kitchen floor when a very strange cast started coming up in photos, so I took a few photos of tile to highlight the problem. I was using my 50mm f/1.8 at the time, and thereafter switched to my 28mm and my 17-85.

After I finished shooting the cats (they decided it was naptime), I took a few more photos outside, but the problem didn't recur. From the way the cast goes across the photos I'm assuming it was a shutter issue, but as I said, it didn't recur.

Settings were: AV, f/1.8, tungsten white balance, ISO 500, servo AF, high-speed shutter mode.

DaireQuinlan

Sure looks as though it could be shutter drag. What was the shutter speed ? Try taking a whole pile of pictures of a white evenly illuminated board or something at a variety of different shutter speeds and see if the problem re-occurs.

-edit- hmm, didn't think about the changing lens thing, was it -only- happening on the 50mm ? Stopped as soon as you switched ? I'd still be inclined to think of the shutter. I presume its a camera with a vertical travel shutter ?

Roen

Check the light source in the kitchen. It's neither a shutter nor a lens issue. It's a product of whatever you have illuminating the room and it's operating frequency.

Or something like that. I can't quite recall the exact details even though I knew it all about a month ago.

Try varying shutter speeds in the kitchen to see if can u make it go away.

DaireQuinlan

Roen wrote:

Check the light source in the kitchen. It's neither a shutter nor a lens issue. It's a product of whatever you have illuminating the room and it's operating frequency.

Ah yeah, thats probably it all right. I take back all my alarmist shutter talk. Flourescent lights in the kitchen ? I don't think halogen or tungsten lights flicker. I guess if your shutter speed was faster than the switching frequency of the lights then you'd get that very effect as the shutter opening moved across the film plane (or sensor or whatever).

Roen

Then again, WB was set to Tungsten, so it may well be a diff cause.

ThOnda

I think that it is caused by frequency of light source too.
Some light tubes have very close frequencies to sensor sampling frequency. Not to mention shutter speeds. But very high shutter speeds.
Try it with the same settings on the daylight and with other lense. It should be ok. Don't worry!