Most printing companies and publishers will request tiff graphics files, and when you save as tiff in photoshop you’ll be given the following compression options (图像压缩):
None – in my experience this usually means a file much bigger than the original photoshop file, if there’s only one photoshop layer
- LZL – Stands for Lempel-Ziv-Welch, a ” lossless data compression algorithm” named after the men who created it. From scantips:
“LZW is most effective when compressing solid indexed colors (graphics), and is less effective for 24 bit continuous photo images. Featureless areas compress better than detailed areas. LZW is more effective for grayscale images than color. LZW is often counter-productive for 48 bit images, the 16 bit TIF file using LZW will probably be considerably larger than one with no compression.”
- ZIP – More detailed, complex images compress smaller with ZIP.
- JPEG – Lossy format, which defeats the purpose of saving as a tif, avoid this one.
Both LZL and ZIP will reduce your file size without affecting quality. The quick answer is: If it’s grey scale or has wide areas without detail use LZL, for everything else use ZIP.
The next option is pixel order (像素顺序), this has two options, interleaved (隔行) and Per Channel (每通道). Here just leave it at interleaved – any program that accepts tif accepts interleaved.
Confession: I used to send jpegs to the printer because the files were smaller therefore faster. In all honesty, I couldn’t tell the difference between a print of a high quality jpeg and a tiff, for a watercolour scan anyway.