Stop down exposure problems

[etrump]

I have been doing some dynamic range and lens testing on my new MF gear getting ready for my first trip using it.

Basically I am photographing a resolution chart and a self made zone system exposure bar.

I am having an unexpected problem when doing stop down exposure testing.

Normally I focus at the largest aperture possible then use the cameras metering to get the exposure.  Then I stop down the lens and either double the shutter speed for each stop or use the cameras metering once stopped down.

The problem I am having is that it always over exposes so my logic is obviously flawed.

Any ideas?

[Jack Varney]

"Then I stop down the lens and either double the shutter speed for each stop or use the cameras metering once stopped down. "

I think you mean that you half the shtter speed, i.e. increase the open shutter duration time.

Have you exposed before stopping down to test the exposure accuracy? Could be a meterring problem or shutter problem.

[etrump]

"Then I stop down the lens and either double the shutter speed for each stop or use the cameras metering once stopped down. "

I think you mean that you half the shtter speed, i.e. increase the open shutter duration time.

Have you exposed before stopping down to test the exposure accuracy? Could be a meterring problem or shutter problem.
[a href=\"index.php?act=findpost&pid=140546\"][{POST_SNAPBACK}][/a]

Exposure before stopping down is perfect and metering is similar to other cameras (at least the Canons I have).  It is just the stopped down exposure with the P30+ that seems to overexpose.

[etrump]

Exposure before stopping down is perfect and metering is similar to other cameras (at least the Canons I have).  It is just the stopped down exposure with the P30+ that seems to overexpose.
[a href=\"index.php?act=findpost&pid=140706\"][{POST_SNAPBACK}][/a]

I guess it was some strange miscommunication between the camera and back.  Reset everything and she works great now.

Go figure.