View Full Version : Full Manual Shooting & Ovservation


Miguel Lombana
May 8th, 2004, 02:14 PM
I just got done shooting the college graduation of my wife from Rollins College here in Orlando and figured that the considtions were steady enough that I could get away with shooting fully manual.

I setup the camera for a custom white balance as the lighting in the place was all white floresent and setup the camera on a quasi-monopod by taking my sticks and closing them all the way tight and just using them for support.

Shutter was locked at 1/60th and gain was setup for 6db to maintain the exposure meter at just a hair under center. The stop was 1.6 to 1.8 average but this is where my question starts.

I noticed that the F-Stop varied during the shoot when I zoomed in tight on some of the speakers where there was less available light coming into the CCD. I thought that full manual meant just that "full manual" I was taken back to find the stops changing. I had to fight the setting during the entire shoot especially when I had to zoom back out and had to (in some cases) ride it back up to 1.8 or 2.0.

Question, is this normal that in fully manual operation the stops would be closing and opening. And also is it normal that that stops will actually go up and down with minimal intervention?

The shoot was stunning, the quality was perfect, always exposed just right, white balanced just right and thanks to Barry's custom presets and running in Frame mode, my wife will be delighted for life!

Just would like to confirm if anyone has seen what I'm seeing on the camera.

Miguel

Robin Davies-Rollinson
May 8th, 2004, 03:43 PM
The lens cannot maintain the widest aperture at the tightest setting on the zoom. This happens on many lenses - even broadcast ones. It's just a matter of the optics.

Robin

Rob Lohman
May 11th, 2004, 09:33 AM
Robin is correct. The camera is in full manual, but the lens cannot
physically do an f1.8 at full zoom. That is a limitation of the lens.
So if you plan to zoom in during recording then set the lowest
value when fully zoomed in instead of zoomed out.

Jeff Donald
May 11th, 2004, 11:29 AM
The term for these lenses is variable aperture and it is a way for manufactures to lower costs without drastically effecting performance.