saving as tif

I am using a PC
When i save an image as a tiff it asks if i want to save it as a mac or PC version.
What is the difference?

And what does LZW compression do?

don't stay up all night worrying about this one. There is no significant difference that I can tell. I'm sure there is a long, drawn out explanation, but the truth is, either file can be opened just fine on either platform.

LZW compression reduces file sizes slightly by removing unused data. Again, no huge significance there either.

hope that helps.

MAC or PC, the difference is like Graphicsguy said... long and drawn out.... but mainly it is just a "bit order" difference. The only time you really have to worry about it is if you are sending the file to someone, in which case I ALWAYS save it as a "PC" version. I only do this because older machines and older versions of Photoshop and other image editing programs on the PC won't identify the Mac version as a .tif file.

LZW compression... does very little to reduce the size of a file... I've had it do more in the way of corrupting tif files...
When instructing my clients to send me files I ALWAYS specify that they leave that option "unchecked".

Hope this helps.