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I think your measurements are off. There is _no way_ that a 1024x768 image is 360 MegaBytes. Perhaps you mean KiloBytes?

In relation to your actual question, i think the issue is that, with HD space so cheap, there is no reason to _not_ keep high quality images around. Who knows what is going to happen in the future, wrt printers, new output devices, handheld hi-res smart pad's, etc etc.

Once you get rid of the high quality stuff, there is no getting it back...

>I shoot at 1024x768 because then each image is
>only about 360MB instead of 830MB. Worse, I then
>compress the JPG's to about 125MB because even
>when I zoom in to the pixel level, I can't see
> any loss of quality.

Errr, surely you mean kB. To be honest, if you're not using it for print magazine work (or, I guess, printing them out large), 1600x1200 is probably good enough. The only advantage to taking bigger (pixel) shots is that you can then crop the original image to just what you want. Having an optical zoom on your camera will negate the usefulness.

It also depends what you use the camera for. Snapshots? Memory aid? or art photography? If it's a point and click, for general hobby use, I'd stick with what you've got, or get a similar Megapixelage that is smaller (something like the Sony Cybershot U20)
http://www.imagestation.com/shop/product/sony/?prodID=10455

Good points have been made already.

It's the usual decision: do I want to future proof my photos capturing and storing maximum data in the most flexible format, e.g. RAW if your camera can do it; or, do I simply "make do" based on my current requirements in a very dynamic and price sensitive market?

Implementing a "high end" strategy for yourself will likely mean a new printer, new imaging software and maybe even a new camera. Mucho dinero. This assuming you have some decent processing power and graphic card capability on you desk. If not, muchissimo mas dinero.

Waiting if it makes sense will guarantee you'll pay less for the equivalent of today's functionality.

But you're an old tech hand, David, you've heard this kind of story before, countless times. What is fun about today in photography is that the cost and performance dynamics that are old hat for us computer geeks, are kicking in big time in a new market sector. The changes will be astonishing; many, many folks are looking over their shoulders. It won't be long before it's hard to find high quality color negative film processing for example.

Now for some theory and a very, very helpful not to mention beautiful, web site, check out Michael Reichman's Luminous Landscape particularly if you follow landscape photography.

Here's a shorter link to an article he wrote on resolution:
http://makeashorterlink.com/?Q58712D24

cheers. ...edN

There is also the question of how much space your compact-flash or whatever has..shooting pics in RAW will eat that up much more, letting you take less pics. Now if you are a useless photographer like me, that optimizes the wrong thing as I take one shot multiple times at multiple angles in the hope that random luck will get me a good shot :-).

So then what to do depends on what your access to your computer is. For me its typically a day thing, or two day thing, as thats long i tend to hike or whatever, unless I consciously decide not to take my laptop. Since flash is expensive, on 2 day trips I will drop quality and take about 64MB worth of flash with me on 2 cards, while on a day trip I will increase the res.

So one also needs to ask, whats your typical laptop access time, and how much flash you are willing to spend on, i think..

First, a mega-D'oh! Um, I mean a kilo-D'oh! Yes, I got the unit of measurement wrong.

Great comments. I should have said that I use the camera for family snaps. And, yes, once I degrade the image, it's degraded for good. But my question is whether those extra megapixels are going to be noticeable by the human eye under any realistic conditions.

Thanks for the help, y'all.

I'm on sandy ground here technically, but I think the key decisions you make with respect to image compression are the first ones, i.e. what are it's dimensions and what "quality" level do I want (meaning essentially, how big a file should I foist off on my viewers?) Click the button and you're going to get a technically decent image.

If you start messing with the dimensions of a compressed file afterward, particularly a JPEG or other 'lossy' compression, every "messing" will degrade the quality because data is lost each time a change is made. It doesn't matter whether you make the image smaller or larger, you loose either way.

Remember too that screen resolution is... there's no other word for it, poor. What is it? 96 pixels per inch? The human eye, viewing a print at arms length will perceive poor resolution below 100 dots per inch.

(This is all very apples and oranges and also rule of thumb-like. Screen pixels do not equal page dots; something per inch on a computer monitor is virtually meaningless. But you should get the general idea.)

The one advantage a screen image has over a print image is its brightness range; it behaves like a slide projected onto your eye; on the other hand, you see prints via reflected light which can be weaker and more diffuse as it strikes your eye; hence the range of contrast of prints will seem lower than screen images. (This can be a real pain if you are using your monitor to adjust your image for print; the visual feedback is deceptive.)

And, the conditions under which the viewer sees the screen image have a major effect on what they see: amount of ambient light, colour temperature of ambient light, calibration of the monitor, CTR vs. all the others., etc., etc.

Notice too I'm using the words "seem" and "appear". At the end of the day, you're the one in charge and you will automatically know whether your work is adequate and that knowledge will improve as you do more and demand more of yourself and your family pix.

Just have fun, mon! ...edN

Dave: Consider this. You may not want to print them now, but you (or your kids) may want them later. I find there is definitely a difference printing from 1024 vs printing at 1600. It is especially evident if you take your memory stick/flashcard/smart media to someplace like Walmart and print via the "photoprinter" that is a high quality ink on kodak/fuji paper. Don't sacrifice the future of your picture for a few kilobytes. My wife makes scrapbooks, and she went from refusing the digital shots to demanding them for the kid's books.

So, David, just buy a decent printer, one that can use more nearly permanent inks (or so they say...). It's hard passing the monitor around when you want to share photos.
I bought a Canon i850 recently and I've been quite happy with it. About $170. Get a USB 2.0 card ($20-40) if you don't have USB2.0 already.
And use the highest resolution/least compression your hardware is capable of. Storage is cheap, history isn't.
Ciao
Craig

I find that, for the most part, people overestimate the pixel count needed for the average user. For high-quality print purposes, the very best resolution is the one you need, however, for the average home or even office colour printer and for even above average screens, a medium pixel cout will do nicely.

That having been said, with inexpensive hard disk space, CD/DVD burners, etc., this advice is perhaps already obsolete -- meaning why not go for the higest resolution your camera can handle, save the original images and reduce them as requried for each specific use.

Just to add another complexity: if your using Mac OS X then you have access to the JPEG2000 format through Quicktime that gives far better compression and has a lossless mode for saving a few bits when archiving.

You know that compressing doesn't nessessarily lose quality - it stores the information in a smaller space, and then requires more computing time to put back into the display mode. Having said that, todays computers do this almost instantly. Why not try taking the pics at higher resolution and compress those.

Also look into getting prints done via a photo lab - they have good printers. However, I'm with you - the pic's look great on a monitor, so then why even bother printing them. Why? Because my wife likes to hang some up on the walls and she also likes scrap booking.

All the best.

So, David, just buy a decent printer, one that can use more nearly permanent inks (or so they say...). It's hard passing the monitor around when you want to share photos.
I bought a Canon i850 recently and I've been quite happy with it. About $170. Get a USB 2.0 card ($20-40) if you don't have USB2.0 already.
And use the highest resolution/least compression your hardware is capable of. Storage is cheap, history isn't.
Ciao
Craig

I am in a dilema. I am doing a show of my work and I am printing 16" X 20" B/W images digitally. I am told I need 15 to 20 MGs per image in order to get the correct resolution for the prints. I have an HP PhotoSmart S20 Scanner that scans up to 2400 DPI (and that isn't sufficient? I have an image printed from 35mm, the same original size as these 16 X 20 images I wish to print, that is 48" X 60" (4' X 5', of course). This pixel thing has me confused. What is the pixel equivalent to an 16 X 20 B/W print and/or the resultant Megabytes size? Am I even asking the right questions? I have to have the prints done immediately in order to complete framing and such for a show being hung next week (the week of 08/14).
Thanks so much for your help...
W.A. Williams