D200 meter with AIS lens problems
This morning, I put my trusty 24mm f/2.8 AIS Nikkor on my D200 for the first time and found that many of my shots were underexposed by about a stop or so. As a test, I put the D200 in fully manual mode, pointed it at a beige wall in my office, and fired off a series of equivalent exposures as follows.
All at 400 ISO, Fluorescent WB, M Mode, Spot Meter.
f22 1/2; f16 1/4; f11 1/8; f8 1/15; f5.6 1/30; f4 1/60; f2.8 1/125
The exposures at f11, f8 and f5.6 are absolutely identical. The shots at f22 and f16 are a bit darker, but not by much. The f4 shot is marginally brighter.
The f2.8 shot is 1/3 of a stop brighter. If I reduce shutter speed at f2/8 down to 160, I get the same exposure as f11-f4. This is a repeatable result.
Next experiment. Shoot a scene at the exposure indicated by the meter, while working my way through all apertures.
At f2.8, meter recommends 1/200. Red histogram reaches the end of the 3rd quartile
At f4, meter suggests 1/125. Red histogram to middle of 3rd quartile.
At f5.6, meter suggest 1/60. Histogram is the same as f4
At f8, meter suggests 1/30. Histogram is the same as f4
At f11, meter suggests 1/15. Histogram is the same as f4
At f16, meter suggests 1/8. Histogram is the same as f4.
At f22, meter suggests 1/4. Histogram is the same as f4.
1) Shots at f2.8 appear reasonably exposed when shot according to the meter.
2) Shots at f4 through f22 are dark when shot according to the meter.
3) At f4 through f22, the meter suggests shutter speeds that are 1/3 of a stop faster than what would be expected based on the metered exposure at f2.8.
4) f2.8 at 1/160 yields the same histogram as f4 at 1/60.
I'm having a hard time figuring this one out. What is going on here? Is this a lens problem, or a meter problem, or both?
#1. "RE: D200 meter with AIS lens problems" | In response to Reply # 0ScottChapin Charter MemberThu 08-May-08 05:26 PM | edited Thu 08-May-08 05:34 PM by ScottChapin
Have you tried something other than fluorescent lighting? Anything above 1/60th second could give you weird results with 60Hz fluorescent.
Powder Springs, GA, USA
Nikonians Team Member
#3. "RE: D200 meter with AIS lens problems" | In response to Reply # 2archivue Registered since 26th Mar 2002Fri 09-May-08 07:27 AM
And at the same time have a look at the small plastic tab on the camera mount...
I've already had it sticking because of dirt, meaning it doesn't flow back (spring) when you go to bigger apertures (hole, not values)
A bit of cleaning and presto all works seamlessly !
"Architecture and Photography are following the same goal ... To sculpt with light !"