jpeg or tiff?

[chris91387]

i'm a little new to the world of scanning and was wondering what you all do with regards to scanning your negs and/or slides.

i'm sending some negs out be scanned and have both jpeg and tiff as an option. my mac is pretty powerful so i can handle the larger file size of a tiff but am wondering if it really makes a difference.

what do you do?

- chris

 

[kbg32]

For anything important, go with a tiff. It is a lossless option. Jpegs will degenerate over time, I'm sure some will dispute this, if the files are consistantly opened and closed. Jpegs are good for emailing and for web postings.

This should help explain things -
http://www.sharpened.net/helpcenter/answer.php?69

http://photo.net/learn/raw/

 

[oscroft]

Hi Chris,

I scan a lot of negs and slides, and if you compare a low compression ("100% quality") jpg with a tiff on a computer monitor, you really won't see a difference. But there's a "but"...

If you want to do any digital work on an image and resave it after each bit of work, a jpg image can start to degrade quite quickly whereas a tiff will not. And if you want the final image to be printed, you will see the differences more clearly (I've been shocked by how bad some jpg images of mine looked when printed, when they looked pretty reasonable on the screen).

So what I do is I scan all my images at 100% jpg, and use these for viewing and for resizing for web use. And if I want to do any more serious work with an image or I want to make a good print, I'll go back and scan it again to tiff.

If you're having yours scanned for you, you probably won't so easily be able to rescan images you might want to do more work with, so I'd suggest getting them all scanned to tiff.

 

[rxmd]

I wish there was a widely supported file format with support for arbitrary bit depths. JPEGs are limited to 8 bits and saving things as 16-bit TIFFs when what you want to use is really 12 bits is rather wasteful.

 

[kuzano]

Bottom line... JPEG discards data

Bottom line... JPEG discards data

The comments here are on target, but to put it in the simplest terms:

JPEG is a destructive process that discards data, supposedly within the tolerance of the naked eye. Save a JPEG ten times and the data loss begins to become visible, depending on the ratio chosen for compression.

The JPEG (Joint Photographers Experts Group) developed the format to reduce file size at a time when storage space and transfer over the internet (or modems) was facilitated by smaller files.

Data is always discarded when you save as JPEG (jpg)