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hi i have a Canon EOS 50 QD wqithout eye control but according to the manual, i still can use the DEP preview using Custom Function ihave tried....succeed and failed again same setting nothing change but sometime the DEP preview works but sometimes the AE lock is overlap the DEP preview while the same setting...confirmed is remained so WHY??? this really gimme a kick and how to see a difference in DEP preview....i can see there's darkening of the view..and a zzzz sound...nothing more...so what should i see? and one more...anbout the RC-1 usage....why must we cover the eyepiece when Selftimer/ remote control is used? thanks

-- HANG SENG (luic@tm.net.my), September 30, 2000

Answers

darkening of the view..

That is it working. With such a small screen and most subjects, it is hard to see the difference. Never give using the function a second thought on my EOS 5, it just does not aid in my understanding of what I am going to get on the slide.

-- Chris Gillis (chris@photogenica.net), September 30, 2000.


I have the same camera, the N.A. version, the ElanIIe.I think I know what's happening, why the depth of field function seems not to work.

Try this: Set your camera in Av Aperture Priority or M Manual mode. Dial in your lens' maximum aperture, the smallest number being the largest. For example, on my Tamron lens, the maximum aperture at 28mm is F4, at telephoto it's F5.6. Now, try the function. Nothing will happen because YOU ARE ALREADY LOOKING THROUGH THE LENS AT ITS WIDEST APERTURE, being F4 at 28mm in my case. Now change the aperture to F8, f11, F16, or ANY (higher number) SMALLER aperture. Now the view darkens when you use the depth of field function BECAUSE THE LENS HAS CLOSED DOWN (called stopping down) TO YOUR SHOOTING APERTURE, the one you set, and you're now looking through THAT aperture. You see? Just let your eye become adapted to the darker view and you will be able to see what's in focus and what's not.

Initially, before using the depth of feild feature, your camera is enabling "wide open fucussing and metering" by maintaining the widest aperture until you release the shutter when the lens will close down to the aperture you set.

I do a lot of low light and night photography and often check my depth of feild to be sure that the region I want to be in focus will indeed come out in my photo in focus. Keep in mind that depth of feild ("depth of what's in focus in the picture", say from in front of a person to behind that person) varies with focal length, distance from the subject AND aperture.

It's also useful for checking your range of focus when shooting groups of people. Regarding the eyepiece cover on your strap. Supposedly this prevents light from entering through the viewfinder and affecting the picture. Perhaps someone else can explain that one.

Feel free to email me if you need anything clarified.

-- Roy Kekewich (roykekewich@yahoo.com), September 30, 2000.


Depth of field preview works by stoping down the aperture, if the lens isn't set for wide open of course. The noise is the aperture closing (stoping down), which is also why the view gets darker. With a smaller aperture, you will have greater depth of field, and this preview allows you to see what will be in focus. Without it, you only see what will be in focus with the lens wide open.

As for covering the eyepiece, stray light can enter the eyepiece, which could cause an inaccurate meter reading. I've never had a problem, but then I mostly use the RC-1 in low light situations that wouldn't cause a problem anyway.

-- Brad Hutcheson (bhutcheson@iname.com), October 01, 2000.


The eyepiece cover stops light from entering there and effecting the exposure metering. The light never shows on the picture since the mirror blocks all of this light while the shutter is open. But the exposure can easily get messed up before the picture is taken. Normally when you're looking through the viewfinder your face blocks enough of this light to eliminate the problem. If you meter in manual mode while looking through the viewfinder and then use the remote control you wont need to cover it since the exposure is already determined. You can cover it with your hand or a hat and it works just as well.

When the viewfinder darkens using the DEP preview, it also expands the depth of focus to what the picture will actually be. This is hard to see, but if you look closely you can see it.

-- Jim Strutz (jimstrutz@juno.com), October 01, 2000.


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