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DEPM20
Jun-11-2008, 10:59 AM
My question is in backing up your photos on a DVD, is the resolution stored the same on each photo no matter how many pictures you store on the DVD ..do you lose resolution by putting too many on the DVD? Does compression cause loss of resolution???? How many is just right????:scratch

THanks

Richard
Jun-11-2008, 11:24 AM
My question is in backing up your photos on a DVD, is the resolution stored the same on each photo no matter how many pictures you store on the DVD ..do you lose resolution by putting too many on the DVD? Does compression cause loss of resolution???? How many is just right????:scratch

THanks

The more compression you use, the more the image degrades. Blank media are really cheap, so there's no reason to skimp.

pathfinder
Jun-11-2008, 12:02 PM
I back up to DVDs in addition to an external hard drive. But DVDs are not terribly handy to use or file, and run the risk of becoming obsolete in the near future.

I am thinking that Andy's solution of Amazon S3 and Jungledisc.com makes more sense in the long run.... As bandwidth to the home goes up, on line storage looks more and more attractive.

Art Scott
Jun-11-2008, 12:44 PM
Changed your post to be itemized ......... corresponding answers below your post here.........

My question is in backing up your photos on a DVD,

1- is the resolution stored the same on each photo no matter how many pictures you store on the DVD ..

2- do you lose resolution by putting too many on the DVD? Does compression cause loss of resolution????
3- How many is just right????:scratch

THanks

1 & 3 - Storing to a disk does not change the resolution.....only you can do that in the processing software....... A single layer dvd holds 4.7 gb no matter what....but it is best to stop at around 3.5 gb.......this is a buffer zone.....I do not know why this works best but it was a recommendation to me when I tried to fill a DVD totally and it would not accept the files to be burned...... movies seem to be different........

The resolution for each photo will be the resolution YOU set it for in your Processing software..............

2- Compression does degrade the photo........ and each time a compressed image is open and closed also degrades it as it is re-compressed and you have no control of what data is thrown out when it re-compresses.......

3- up to about 3.5 gb. as mentioned above......so how many really depends on how large your files are..... I shoot in Raw and I try to file all my raw files along with their respective processed jpgs on the same disk..... I also have disks with just the raws and a categorized disks with the jps and all of this is on external hdds by raw+ processed jpg and categorized jpg

Hope this helps

One back up I highly recommend is SMUGMUG....best lace for backing up all of your jpgs.............

Rhuarc
Jun-11-2008, 02:15 PM
And a backup I can highly reccommend for RAW and other stuff is Mozy.com.

It is $5 a month for unlimited storage (as long as it is for personal use) I have 60GB backed up right now there, and it seems to work great.

Scott_Quier
Jun-12-2008, 04:07 AM
2- Compression does degrade the photo........ and each time a compressed image is open and closed also degrades it as it is re-compressed and you have no control of what data is thrown out when it re-compresses.......

This is almost correct. Compression does degrade the photo. The slight mis-statement here is that the photo quality is not degraded with each opening of the photo. It only the compression during a save operation that degrades a photo. So if you have a jpg that you repeatedly open AND save (remember, JPG processing is, among other things, a compression process) your result will be a progressively more degraded photo - and the effect is not linear but exponential.

That having been said, if you start out with a high quality JPG and re-save it as a high quality JPG, the quality degradation will not become visually noticeable right away. Talking with Shay Stephans last year, he related the results of an experiment he performed wherein he took a high quality JPG and repeatedly opened and saved it as a high-quality JPG. It was not until the 10th generation (or there abouts) that he began to notice any significant degradation. Of course, YMMV and "significant" is very subjective.