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Old Dec 3, 2007, 12:28 AM   #1
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This may seem like a silly question but I'm going to ask it anyone, hey someone may be asking the same thing (I hope). We have five P&S digital camera at home each of them has a optical zoom which can be increased by using a digital zoom. This works okay for some shot but not always. Anyway, the question is do DSLR have a digital zoom mode on them like the P & S use?
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Old Dec 3, 2007, 5:40 AM   #2
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No, DSLR's use only optical zoom
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Old Dec 3, 2007, 7:52 AM   #3
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I disable Digital Zoom on cameras that have it. That way, I don't accidently use it.

All Digital Zoom is doing is cropping an image. You can do the same thing with an editor. Most models crop, then enlarge the image back to the original size.

That's why image quality is degraded (because you have far less of the original pixels representing your subject, and the camera is adding pixels back in that were not captured by the camera using interpolation.

Some models have Digital Zoom modes that only crop (versus crop and enlarge). For example, Sony's "Smart" Digital Zoom works that way. But, this feature requires that you use lower resolution modes.

In any event, you can crop and resize with an editor later versus using digital zoom.

Just keep in mind that you can degrade image quality signfiicantly either way (in camera or later with an editor).

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Old Dec 3, 2007, 12:12 PM   #4
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I find in using the Panasonic cameras I use, the Extended Optical Zoom option they givedoes a very good job. Unlike digital zoom, there's no "adding back in" of pixels by the camera. It just utilizes a smaller area of the sensor. As long as you don't plan to make a 16x20 print of such a file, it's not a problem, but no, no DSLR will give you that option. You just have to buy a longer lens.

Here are a couple of images where I used an FZ8, which has a full resolution zoom range of 36-432mm, but by dialing the resolution down to 3MP, the optical zoom range is extended to 648mm. The only limit to the quality of an image at that point is your ability to hold the camera still enough at that extreme magnification...







Canon also offers this type zoom...I believe it's called "Intelligent Zoom", or something like that. The one advantage I see in using this vs. cropping on the computer later, the meter reading is relegated to only that part of the sensor being used to record the image, so it can be more accurate than metering a larger area and cropping off later.
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Old Dec 3, 2007, 12:49 PM   #5
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Thanks all for the answers. Really didn't think DSLR had any type of digital zoom, then again until a couple of weeks ago I didn't think any DSLR could shoot in Live-Veiw mode either. Hey the new stuff coming out is changing so fast it's hard to keep up to date with everything. Of course DSLR not having a digital zoom meansI'll just have to tell the wife have to buy an extra lens, oh shoot :G. That is after we get the DSLR camera, still (she is reading) looking at all models on the market.

Thanks again,

Craig
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Old Dec 3, 2007, 2:20 PM   #6
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It's easy to do "digital zoom" with a DSLR, you just crop the photograph in your favourite image editor and then up-rez it to the size you want. That's all that digital zoom cameras do anyway.

"Digital zoom" is not a real feature it's just a marketing fudge. If someone is pushing it to you then run a mile for they are out to con you.
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Old Dec 3, 2007, 4:32 PM   #7
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"It's easy to do "digital zoom" with a DSLR, you just crop the photograph in your favourite image editor and then up-rez it to the size you want. That's all that digital zoom cameras do anyway. "



True, you can do the same thing in post processing but it is nice for framing a shot. Digital zoom is not something I use much (usually turned off) anyway but was just curious. After all you never know what manufacturers are going to do next.

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Old Dec 3, 2007, 5:29 PM   #8
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You get far more control cropping and/or resizing an image in post processing, versus tyring to use digital zoom with a camera setting and "cropping on the fly".

You can also find far more sophisticated algorithms for resizing images, using a powerful PC, versus the camera's processing trying to accompolish the same thing in a split second between shots.

Again, I keep Digital Zoom disabled so that I don't accidently use it. If you do use it, you're going to degrade image quality with most cameras, unless you're shooting in lower resoltuon modes.

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Old Dec 3, 2007, 5:39 PM   #9
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Calicajun wrote:
Quote:
...This works okay for some shot but not always. ...
I have found digital zoom useful on only one occasion, while on holiday in the far north of Scotland last summer. It settled a family argument.

In dull and drizzly weather, my wife, my 16yr-old son & I gazed at an island just offshore from Durness, the village nearest to Cape Wrath, the NW extremity of mainland Britain. I maintained I could see a hole right through this substantial island, but the others were dubious. Our 8x30 binoculars failed to resolve the argument. So I got out my (then very new) Kodak Z712is superzoom hybrid, and took two shots at full (432mm equiv) zoom and wide open aperture, (f/4.8, hand-held), one at ISO 200, 1/512s, without digital zoom, and one at ISO400, 1/645s, with digital zoom.

This is the full frameof the first, resized & sharpened,and the reply below is a pair of 1:1 pixel for pixel clips straight from the camera images of the two shots. Displayed on the LCD screen on the back of the camera, and further digitally zoomed in by a factor of 8x, it confirmed the finding of my ancient eyes (plus driving spectacles). There is indeed a hole! (See next reply for 1:1 clips)
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Old Dec 3, 2007, 5:41 PM   #10
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