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07-08-2009, 01:31 AM   #31
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QuoteQuote:
As for the error at narrow apertures...this is to be expected. The amount of light reaching the meter at those apertures is often below its sensitivity.
Steve : this is a pretty common statement, but it's totally false... Try this in plain sunlight (on a very bright objet), and you'll still see the same behavior, even though the light coming through the lens is way above the Ev bottom limit of the sensor...
Moreover, using a LL60 removes this flattening... So this is really an effect of the stock screen.

07-08-2009, 02:36 AM   #32
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QuoteOriginally posted by stevebrot Quote
Interesting. What firmware version are you using? I tried to implement this fix, but could not find that option.
Steve
Version 1.30.
07-08-2009, 02:55 AM   #33
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Version 1.30 options for "Green Button in TAv & M:"

1 Program Line
2 Tv Shift
3 Av Shift
07-08-2009, 09:20 AM   #34
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QuoteOriginally posted by dlacouture Quote
Steve : this is a pretty common statement, but it's totally false... Try this in plain sunlight (on a very bright objet), and you'll still see the same behavior, even though the light coming through the lens is way above the Ev bottom limit of the sensor...
Moreover, using a LL60 removes this flattening... So this is really an effect of the stock screen.
Totally false? Well, perhaps I should redo my controlled exposure series tests that the statement was based on. My results showed that the severe underexposure at smaller apertures (3 stops under at f/22 on one test), essentially went away in bright light. With adequate light at f/8 and narrower, the general pattern was for correct exposure or a mild over-exposure (~0.5 stop).

As far as the LL60 removing the flattening...I don't particularly want to be contrary, but I calculated the EV at the sensor and it was below EV 0 (ISO 100) at those smaller apertures. According to the published specs for the K10D, I think that is below meter sensitivity. Moreover, my tests seem to indicate that the K10D sensor becomes non-linear at about EV 1.5 (ISO 100) which does not help matters any.

Steve

(I guess I really should publish my exposure series graphs...)

07-08-2009, 10:51 AM   #35
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QuoteOriginally posted by Duck Dodgers Quote
Version 1.30 options for "Green Button in TAv & M:"

1 Program Line
2 Tv Shift
3 Av Shift
I set it to #2, Tv Shift. Sorry if I caused any confusion.
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