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Old May 8, 2004, 10:30 AM   #1
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Hi folks

I'm looking for an SLR that I can use to shoot outdoor macro subjects (mushrooms mostly). I'd like something like a D70 but don't relish the thought of laying prone in the mud to frame my shot, so I need something with an LCD that can be used as a live view finder. An articulated one gets bonus points but is not absolutely necessary.

TIA


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Old May 8, 2004, 10:38 AM   #2
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For a variety of reasons, there are no SLRs that have a live video LCD (i.e., one that can be used as a viewfinder), sorry. :sad:
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Old May 8, 2004, 11:09 AM   #3
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Thanks Zal.

Can you expand on the reasons? I know the Olympus E10 and E20are set up that way, but I don't know if they're not concidered "real" given their fixed lenses.

TIA
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Old May 8, 2004, 12:05 PM   #4
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I believe the reasons have to do partially with the sensor in the camera. It isn't on all the time, its only used when the shutter button is pressed.

One reason for this is it reduces heat in the sensor. All electronic devices produce heat when turned on. But heat is bad for a digital sensor because it increases noise in the picture. The market that digital SLR cameras are aimed at want higher quality-lower noise cameras.

I also don't think that their sensors are designed to take a picture that quickly... they couldn't update the LCD fast enough to make it usable that way. Again, quality over features.

So my bet is that it isn't possible in the way they design the camera. (I'm not saying that they couldn't do it, but that they choose to design the camera so that it isn't possible.)

Personally... I see the benefit from not having to look through the view finder some times. Hold the camera over you head and take the picture... that kinda stuff.

And as to the E10 or E20... they are real cameras, and they are SLRs. Techincally an "SLR" doesn't say anything about replacable lenses, although almost all of them do have that feature too.

Eric
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Old May 8, 2004, 12:15 PM   #5
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The reason you can't use the lcd as a viewfinder is that most of the time the sensor is hidden. The mirror and shutter are in the way.A DSLR is set up just like a film slr (single lens reflex)camera. When composing the shot, the light enters the lens, bounces off a mirror and through a prism into the viewfinder. When the shutter button is pressed, the mirror flips up out of the way, revealing the shutter. The shutter's first curtain opens, revealing the sensor (or film) and then the second curtain follows at the appropriate time to end the exposure. Then the mirror flips down and you are ready for another picture. I believe this flipping action of the mirror is where the "reflex" comes from. Now do you see why the LCD won't work until you take the picture?
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Old May 8, 2004, 7:13 PM   #6
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By definition, an SLR (Single Lens Reflex) camera is one where the user looks through the lens (using a mirror or a prism). The viewfinder shows exactly the same subject that will be exposed to the film (or in the case of a digital camera, the sensor0.


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Old May 8, 2004, 7:39 PM   #7
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While I agree that is why you wouldn't have it as an "always on" feature (because you would never actually be looking through the lens) I have wondered why they don't have it as an option when mirror lockup is set.... and that is why lead my down my line of reasoning.

Eric
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Old May 8, 2004, 10:31 PM   #8
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LTBerry has it right on--the reason is partly due to the mechanics of the camera itself. The sensor is physically blocked by the mirror and the shutter.



That's just one reason though--to add and answer yours and eric's question, the other reason is that the sensor in a dSLR does not carry live video, which is needed for a live preview. The sensors in dSLRs are optimized for image capture only. There are several OTHER sensors, including one for exposure, one for focusing, etc., all optimized for thier specific jobs, which is the reason why dSLRs are so much faster at everything than digicams (like focusing, shutter lag, etc). In a digicam, the main sensor handles everything--focusing, expsoure, image capture, video capture, preview, etc... So that one poor sensor is swamped by a variety of tasks.
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Old May 9, 2004, 9:40 AM   #9
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An SLR with the normal digicam preview/video/... could be built simply by using a half sivered mirror instead of the flip-up mirror. Cannon (?) built a chemical camera of that kind many years ago. Silent (no mirror slap), but a dim viewfinder (it only gets half the light), and low sensitivity (film/sensor only gets half the light).

Could be done, but how many people would buy it? Not many bought the chemical version, but silence was its only advantage. The extra features in a dSLR would be a further advantage, but dSLRs already have dim viewfinders due to the "focal length muliplier".
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Old May 9, 2004, 10:42 AM   #10
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FYI

http://www.photozone.de/2Equipment/reviews/eosrt.htm

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