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Discussion Starter · #1 ·
I am sort of new at this stuff (playing around with Photoshop) and am looking for some advice.

I am scanning & saving family photos using photoshop with the idea of having everything saved in a digital archive and possibly printing off some of the images down the road. I have noticed that saving a file in the TIFF format leaves me with a very large file (8MB typically) whereas saving in jpeg at the 10 setting (around 300 dpi) results in a file of around 2 MB. I can also save a file as a TIFF and then have a choice of compressing it with a jpeg option which will bring it in at around a 1.2 MB size. Now I am getting really confused!

I want to save the files at a high enough quality that they could be printed (5X7 or 8X10) with good resolution and at the same time keeping file size down.

Which way do I go???
 

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Compressed TIFFs use the LZW compression algorithm which is lossless.

I would save as TIFF to preserve quality, despite the larger file size. You can also enlarge a TIFF image in Photoshop more cleanly than a JPEG. Enlarging a JPEG will always result in artifacts (those ugly jaggy lines).

Also, creating a digital archive to exist soley on your hard drive is a really, really bad idea -- your hard drive will fail at some impossible to predict point in the future, so you should be archiving to your hard drive, then backing up to CD or another hard drive, which will also solve the file size problem.
 

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I should also point out that each time you resave a JPEG, the compression algorithm is reapplied, resulting in further image degradation.

It's kind of like making a photocopy of a photocopy, with each subsequent copy becoming less legible than the one that came before it.
 

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Discussion Starter · #4 ·
Thanks for your guidance. Advice taken on both counts.

So you have got my curiosity up re the potential failure of the hard drive. Help me understand why there is the risk you touched upon. (PS I also have a slightly silly amount of music on one of my drives)

Curiosity the cat here
 

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Read the other post about scanning, and what happens to jpegs. Tiff files are pure raw information files saved in the highest possible format, while jpgs are compressed information files, and throws out and data the computer doesn't need to display the image. JPEGs are only really used for web publications, and really shouldn't be used for anything else. Digital cameras use jpeg technology because a camera that can take 36 pictures on a 36 mb card will always sound more impressive than 2.

A good analogy of jpg vs tif is mp3 or m4p vs aiff in the music world. A mp3 is good enough, but for those with decent equipment will hear the difference in the two formats. So a jpeg is good enough if all you want to do is look at it on screen, but if you want a quality print, stick with tiff, it holds all the information you don't know about, and will look better when you print.

With cds usually costing less than 50 cents a disc, using more space shouldn't be an issue, plus a disc or directory with less images will be easier to find a particular image in the future.javascript:void(0) For example a properly labled cd with 100 images is a lot easier to find an image then one with 500.

Also 8mb for an image is not big at all, try again when you're scanning 100 mb files.

vince
 

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The risk is due to the fact that your hard drive is a mechanical device that won't last forever. I've had hard drives fail on me but I've never lost important data because I always back up to a second internal hard drive, and then I will dump files onto CDs (or DVDs) if the drives get too full.

The cheapest and most efficient backup method is a second internal hard drive. A hundred bucks will get you tons of storage, perhaps 100 to 200 gigabytes, so there is no reason to risk losing everything by not backing it up.

You can make a bootable backup copy of your entire system but I never bother with this. Simply create a folder for your music, a folder for your documents, a folder for your photos etc., and drag and drop your files to be backed up onto those folders. Simple and effective.
 
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