Joe I'm not sure I got your point, but I claim that the film exposure might be affected from stray light entering the camera through the uncovered finder in any case, would it be the camera metering or external one. Suppose you are shooting during daylight (implying short exposure). Looking through the viewfinder, the camera metered value X for the exposure. Then, releasing the shutter would produce metered exposure on he film. However, if just prior release you moved your head to the side exposing the viewfinder for the ambient - the exposure metered by the camera is affected immediately and it will produce exposure Y which will be actually used for particular frame.
Now you say: let's use external meter to avoid such effect. OK, suppose you shot in M (manual metering mode) with uncovered finder. You metered the scene y some kind of handheld meter and got correct exposure for that scene which you dial into the camera. Releasing the shutter would indeed imply this exposure value , however, there is additional light hitting the film (comes through the uncovered viewfinder) which also contributes to the overall exposure so you may end up with somewhat overexposed frame. That brings me to another confusing question: As I outlined originally, while metering by camera's meter looking through the finder it calculates an exposure X. Now, uncovering the finder, the camera detects additional light amount entering (though it is obviously unable to realize that the additional light source isn't one reflected from the scene being photographed, but rather the excessive one) and tries to compensate for that by altering the initial exposure thereby causing by certain final underexposure of the scene being photographed. The confusing issue is how the additional light source coming out of the scene to be shoot (not the one reflected form the actual subject) hitting the film plane affects the proper exposure. Perhaps it really (positively) contributes to the overall exposure so in this case the camera is correct taking that into account and compensating accordingly (by less exposure), or contrary, this light coming through the finder is really disturbing and negatively influence the exposure of the film so originally the camera should take that into account but then the camera's design must take care of cutting that light significantly ? Perhaps more experienced photographers on the List may clarify the issue ? Regards, Alex Z -----Original Message----- From: [EMAIL PROTECTED] [mailto:owner-eos@;a1.nl]On Behalf Of Joe B. Sent: Saturday, October 19, 2002 4:41 PM To: [EMAIL PROTECTED] Subject: RE: EOS3 viewfinder and eyepiece shutter On 19/10/02 at 15:52, [EMAIL PROTECTED] (Alex Zabrovsky) wrote: > Thanks guys, however, the case I was referring to isn't quite suitable for > the solutions offered (except probably of taping as offered by Peter). > Blocking manually by holding say a cap, black sheet of paper or something > like that would be fine > for relatively short Bulb exposures, however speaking about minutes, tens of > minutes and hours would be different case. > Say, shooting star trails you world open the shutter for several hours > during which I doubt you would be willing (or be able at all) hand-hold > anything manually. :-) > > Frankly, I wonder why Canon didn't build into the body the eyepiece curtain > as available on other pro bodies (Minolta 9, probably Nikon adequate bodies > and 1V). > > Regards, > Alex Z Hi Alex- I might have missed the point of this, but- if you have the shutter on B, the internal meter isn't controlling the exposure time in which case stray light coming through the eyepiece wouldn't affect it- surely? Joe B. * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
