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Old Dec 9, 2005, 2:12 AM   #1
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My old S110 Elph isn't working properly so, after much reading, I am about to buy a Canon S80 to replace it.

I was wondering if its advisable to always take pictures at maximum resolution (8MP on the S80). How does a camera 'downsample'? Does it leave out every n'th pixel? Does it take a full 8MP picture, then throw away some pixels?

I like the idea of having 8MP available for when I want it, but memory space is used up fast at that resolution, and for many situations a lower resolution would suffice.

My main concern is that lowering the resolution will introduce more noise, or blurriness or some sort of processing artifacts.

So, basically, is shooting below the max. resolution good, or evil?

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Old Dec 9, 2005, 7:41 AM   #2
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It seems that most/all cameras downsize by "averaging" adjacent pixels. A few cameras use the center part of the sensor to increase the burst rate and length - one of the few cases where digital zoom makes sense.

IMHO, you should always shoot at the highest resolution unless you have a good reason to do otherwise. You can always downsize later, but you cannot recover detail lost by shooting at lower resolution and/or very agressive JPEG compression.
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Old Dec 9, 2005, 9:52 AM   #3
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I agree with Bill. Get a larger card. You never know when you will get a great shot, and you will want that shot at best quality.

My mother in law starts looking for condos in Florida every time it gets really cold in NY. She sends me places she is interested in and asks me to look at them for her. I take about 40 photos and send them to her. Since I know I will never want the images for any reason other than to e-mail them to her, I shoot those at lower resolution. But that is the only time I have ever lowered the resolution on any of the 5 digital cameras I have owned.

I don't think any digital cameras disable pixels for lower resolution except for various types of digital zoom.

One downside of shooting at lower resolution is that you usually have to shoot at a lower JPG quality as well. A computer downsample of a higher quality JPG would be better than having the camera downsample and then save at a lower JPG quality.

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Old Dec 9, 2005, 9:40 PM   #4
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Quote:
you should always shoot at the highest resolution unless you have a good reason to do otherwise. You can always downsize later, but you cannot recover detail lost by shooting at lower resolution and/or very agressive JPEG compression.
Quote:
A computer downsample of a higher quality JPG would be better than having the camera downsample and then save at a lower JPG quality.
I agree. Get a big card and use the highest quality settings. Then, if you want to email them or something, make it smaller on the computer where you have tigher control of resolution, compression, and file size.
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Old Dec 10, 2005, 10:33 AM   #5
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I would suggest 1GB card, prices of cards are now quite stable so I don't see much point in waiting for pricedrop of those.
Also I wouldn't suggest even thinking other than best JPEG setting considering file sizes
http://www.dpreview.com/reviews/canons80/page5.asp
(sure empty sky or smooth wall fits to those without degrading quality but detailed shots will surely suffer much)


I have 8MP KM A2 and with best JPEG quality normal pics take about 5-6MBs while largest one has been 7.5MB.
Also I'm intending to take some harder situation shots in RAW (11.5MB) so I'm finding 1GB card as quite small so I'll very propably buy 2GB card before next summer.


Also remember that if you take videclips those take space at much faster rate.


Considering archiving of pics big HDs are very cheap and DVD-writers aren't much more expensive than CD writers which are very cheap, price ratio between blanck medias is also same making DVD better choise in every way.
(but no matter do you use CD-Rs or DVD+/-Rs it's better to use good quality medias)


PS. Previously I had 5MP Minolta 7i which makes about 2-3 MB JPEGs at smallest compression and when I was in one week trip I took ~600 shots worth of 1.5GB.


slipe wrote:
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One downside of shooting at lower resolution is that you usually have to shoot at a lower JPG quality as well.
I've never seen that kind limit.
Logically it would be just otherwise considering size of required buffer memory.
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Old Dec 12, 2005, 1:27 PM   #6
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{One downside of shooting at lower resolution is that you usually have to shoot at a lower JPG quality as well.}

I've never seen that kind limit. Logically it would be just otherwise considering size of required buffer memory.
I just grabbed data for the Oly Stylus 800 at random. These are the resolutions. You will notice to go down the first step in resolution you drop two qualities, from SHQ and HQ to SQ1. Going even lower in resolution can drop you to SQ2. This is pretty standard in digital cameras. I guess logic doesn't have anything to do with it.


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