p.1 #1 · Apparent A1 Metering Problem After Firmware Update
Prior to a trip that I took in June, I updated my A1 bodies to the newest firmware. While traveling, there were numerous times when the camera would randomly greatly overexpose or underexpose instantaneously. The only thing that I could do to get the camera to return to normal was to turn it off and then back on. This was not an issue of accidentally changing settings. It occurred several times. I have no idea why this happened and it was incredibly frustrating as I missed some wildlife shots because of it. I tend to switch between spot metering and multi metering, and really don't know if the issue was related to one of those options, or if the issue was metering at all. General settings were Manual mode for shutter speed and aperture, and auto ISO.
A few things that I consistently noticed:
1. Problem was certainly repeatable and occurred multiple when using the 300/2.8 with either the 1.4x or 2x (it happened with both TC's)
2. Problem would happen when shooting, but it also happened several times when starting the camera up from sleep mode while we were driving in a vehicle.
3. When it happened, changing settings did absolutely nothing. Camera had to be turned off to get back to correct exposure.
4. Overexposure happened much more frequently than underexposure.
5. Over/under exposure was at least three stops and could have been more. When overexposing, frame was almost all white with just a little bit of image in the frame. Underexposure was completely black.
6. I don't recall this happening with any other lens, so I guess that it could be somehow be a problem with the lens rather than the camera.
Has anyone else experienced this issue? I don't recall it happening before the firmware was updated. Any thoughts on how to correct the issue?
p.1 #3 · Apparent A1 Metering Problem After Firmware Update
ronno wrote:
Guessing you sorted this by now…
My only guess would be aperture blades sticking…
It has not been sorted out yet. I had not thought about the aperture blades, which I suppose is a possibility. However, the lens is only 1.5 years old and itself seems to operate perfectly as far as I can tell. I will see if I can determine whether or not the aperture blades are a problem - thanks for the idea.
p.1 #5 · Apparent A1 Metering Problem After Firmware Update
ronno wrote:
Does it occur with other lenses??
It did not, however, when I was traveling recently, I only used another lens on the camera for a pretty limited time. The 300 with or without a TC was on the camera at least 95% of the time. I have not worked with the equipment any more since I returned, but need to pull it out and see if I can figure it out. I guess the first thing would be to clean the contacts on the camera, lens, and tc mount to see if that helps.
p.1 #6 · Apparent A1 Metering Problem After Firmware Update
Are you set to spot metering, and if so, is it tied to the focal point or the center? When you are shooting at 420 or 600mm, the part of your scene that is metered is small (relative to what your eye would take in without the lens.). It is easy for your intended subject and what is metered to be very differently lit.
p.1 #7 · Apparent A1 Metering Problem After Firmware Update
Grenache wrote:
Are you set to spot metering, and if so, is it tied to the focal point or the center? When you are shooting at 420 or 600mm, the part of your scene that is metered is small (relative to what your eye would take in without the lens.). It is easy for your intended subject and what is metered to be very differently lit.
Jim
I switch between spot and multi metering, based on the situation. I understand what you are saying about spot metering. The issue that I was having was that no matter what I did, the over or under exposure would not change unless I turned the camera off and then back on again. It did not matter if I moved the frame around (effectively moving the spot metering point if spot metering was active). Even changing the exposure compensation did nothing.
