JCO

Listen, you mindless nincompoop, the comment I made with regard to  
variation and body controlled aperture setting is expressed in  
exactly these words:

> The remaining four rows show what the in-camera reflective meter  
> nets at the same aperture settings ... first two using the body  
> controlled aperture, the next two using the lens' aperture ring.  
> Note that there is more variation here between f/4 and f/16, even  
> with the body set aperture setting, because you're hitting the  
> bottom of the meter's sensitivity range. Then, in the next two  
> rows, you see that at f/16 the Manual-semi automatic stop down  
> setting really does bottom out and the f/16 exposure is well  
> underexposed.

which says that the reason for some variation at this setting *EVEN*  
with the body controlls aperture setting is that you're hitting the  
bottom of the meter's range.

Look at the exposures in the table, K10D column, sixth row: the  
camera set ISO 200 @ f/16 @ 8 seconds ... the K10D meter has a range  
of EV 0.0 - 21 EV (given ISO 100, 50 mm F1.4). With body-controlled  
aperture, lens on the "A" position, metering is wide-open at f/2, so  
the meter is being asked to perform at EV -1, one stop past its rated  
limits of accuracy.

Some variability at the bottom limits of the metering range in any  
metering system is quite normal, certainly past is, and the metering  
variation is about 0.3 EV. That's very acceptable performance in my  
book.

G


On Jan 24, 2007, at 7:56 PM, J. C. O'Connell wrote:

> What is "allowed" by the mfgr. and what is acceptable to the
> photographer is two different things of course. 1/3 stop may be  
> fine for
> color neg film but it might not be for DSLR if you dont want to have
> to tweek all your images to get them to match on density
> when changing the fstop/shutter speed combination under
> same lighting conditions. He specifically stated there was
> visible ( not just measurable ) differences didnt he?
> jco


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