From: "Emily L. Ferguson" > Sombody help me understand. > > After you've gone to the trouble to scan, spot, color correct and > othewise adjust a file, why in heaven's name would you consider > saving your master copy of it in a lossy format? because the loss will only occur if you manipulate the image, or store it at a high rate of compression. If it's a final image, ready for print, then printed from a jpeg or a tif it will look the same.. the only difference is that the TIF file will take up considerably more space than the JPEG. There is no loss to an image by storing it as a jpeg. Open it, save it, open it, save it, open it, save it and you DO have data loss, but if you treat it as a final pre-press format as many pre-press people do then it's a beautiful format. > And what sort of printer doesn't understand that jpeg is a consumer > format, not a professional one? JPEG is not a consumer format, neither is TIF a professional one. PSD's, PDF's, TIF's, ANI's, JPEG2000's, CUR's, CPT's, DCM's, EPS's, GIF's, BMP's, IMG's, PBM's, PCX's, PNG's ( a nice format btw), RAW's... etc, all have their uses in both the professional and the consumer world and each have their particular uses > Jpeg is good for web sites and email transmission of comps. After > that, forget it for permanent storage. nothing gets lost while a JPEG is in storage .. and GIF's are often better for web sites. The major risk to image data is when information gets shed while the image is manipulated - simply rotating a jpeg results in data loss! The odd thing i find is that the major benefit of JPEG , the ability for the format to preserve data in a smaller file size is overlooked, and TIF, which has the benefit of not losing data is touted as the be-all and end-all of image formats. k
