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garyasta
19-11-2002, 12:38 PM
I have recently purchased a digital camera and was wondering which format is the best to save the original images on CD for subsequent editing or other processing.

I understand that .jpg or.gif are the best for sending by e-mail or for web pages. Where does .tif etc, come in. ?

Gary

Chilling_Silence
19-11-2002, 12:45 PM
Gif, JPEG and PNG (Portable Network Graphics I believe) are all great for transferring via the Net coz they're small, compressable, viewable in web browsers, and some of those formats accept transperencies in the image, and also animation in the image.

To my understanding, .tif images and others, are attempts at creating cross-platform compatible images that everybody will want to use, however, JPG and GIF were the first to be widely used by web browsers and took off. That is my understanding of Image usage.

If you're wanting your relatives or whatever to see the images on the CD, then GIF, JPG are best candidates, and then PNG If their OS is fairly new (I think ME upwards supports PNG natively). Or, if They've got IE6, then PNG would be best.

This is not gospel and I can gauranteee that there are different opinions, when it comes down to it, its personal choice, and what your image editing software will let you save as in the end. If you have MS Office, make sure you install all the little extras, like MS Photo Editor and also the convertors.

Hope this helps :)


Chilling_Silence

SKT174
19-11-2002, 01:41 PM
Depends on the camera .. if there is a RAW settings, that's the best to use as RAW format records the image data as captured by the camera's CCD without further processing.

RAW images are still compressed but the compression is reversible so that a high quality image can be obtained from the decompressed file without any loss of image quality.

In addition, although a RAW file is larger than an equivalent JPEG file (which compression can't be reversed), it is still only approximately 1/4 the size of an uncompressed RGB TIFF format file.

Cheers

Graham L
19-11-2002, 02:13 PM
If you are going to do any processing on the pictures, you should save in a format which does not lose any quality. That rules out JPG and GIF. They are both "lossy" compression techniques. The cameral will have a preferred (default) format when it transfers the images to your computer.

Save the file in that form. When you have done any processing (even trimming the borders) save the ooutput as JPG. Experiment a bit and you will find a good compromise between size and quality. But it's best to keep the original, because you can't get back to the original quality from a JPG. It is a one way process.

GIF is "slowly" becoming obsolete. PNG is the replacement for that.

garyasta
19-11-2002, 02:24 PM
Many thanks to "Chilling_Silence", "SKT174" and "Graham L" for their responses. The latter respondent provided the info needed as I wish to retain the maximum detail for each image as it is saved. Later processing would then have all detail needed for the best reproduction.

Thanks
Gary

Heather P
19-11-2002, 10:03 PM
The photo will come off your camera in a large detailed format - such as tif. Keep these - they are like the negative for a film camera. Lose the original and you're stuck with poorer quality images to work with in the future.

To send photos on the net - change them to jpg format. Smaller file size and everyone with a browser can use them.

Jpgs are for photos
Gifs are for limited colour images - such as logos, cartoons etc. They can also have transparent backgrounds and be animated.
Png (pronounced ping) theoretically combine the features of jpgs and gifs - but I still haven't figured out how.

If you are sending photos via email - reduce them in size. Family members have been known to send photos that won't fit on the screen, are too big to print and take ages to download. We see the baby's toe - and have to scroll sideways to see it's head.

Chilling_Silence
20-11-2002, 11:21 AM
PNG's dont do animations though do they?
I've found the quality to be better than both formats for a filesize thats the same.