Should I save as TIFF or PSD?

Question

Hello, I have been going 'round in circles trying to decide whether to set my Lightroom external editing pref's for Photoshop as PSD or TIFF. I've very recently downloaded Photoshop - I'll be using it after I've done what I can in Lightroom, just for photo's - I've never used 'layers'
1) Can anyone advise which might be best - I read somewhere that PSD might be easier (or necessary) if I need to re-edit. I also read PSD could be a good idea as it would be easy to see which is the master edit, and which files have been saved as TIFF, for print say
2) I also read that you should never flatten a file, at least not until you need to (ie: save as TIFF for print) - any thoughts?
3) My thoughts (mixed up though they may be!) are to say edit layers etc in PS (either TIFF or PSD) then just press 'save', but not flatten layers (I understand the PSD or TIFF will then be alongside my original raw file back in Lightroom, as LR/PS automatically does this). Then say for print I would then  'save as' a TIFF (ie: for printing), or JPEG (ie: for web), and this would automatically flatten the file. If this is correct, say I started off with the un-flattened PSD for example, would I need to firstly make a copy of the PSD, or would just doing a 'save as' still keep the original PSD 'master file'? Also, after I say did a 'save as' for a TIFF, could I then just delete the TIFF and do another 'save as' if I wanted to do another print in the future, or better to just keep the TIFF in Lightroom alongside the raw, master PSD or TIFF / JPEG?
4) I won't be doing huge amounts in Photoshop, so would it be worth looking into using 'smart images / smart filters' - I'm just thinking that if document is not being flattened anyway would it be worthwhile?
Sorry about all the questions, but the more I read the more confused I become - I'm the sort of person who likes to know what they are doing before they do it if that makes sense (probably not!!)
Thanks, Roy
Message title was edited by: Brett N

Answer 1

Here's my thoughts...
1. You are a bit confused and I wonder how you can determine a file is a PSD or a TIF by looking at it?  Not all print drivers can recognize PSD's, but can recognize TIF ( this means almost all output devices can interpret TIF's no problem ).  That said, PSD's can manage layers better than TIF's which add to file size each layer you include in the TIF.
2. Never say never.  This all depends on the file's use.  Layered TIFs can add complexity in which a print driver can or cannot deal with.  As you work on an image, you may want to merge layers for whatever reason(s) and you always have the option to flatten whenever you feel like it.  However, It is also a good idea to dupe the file as you move along.  That means you always have a layered version to fall back on should you need to edit later on.  I also Place transparent PSDs in Illustrator files with no problems.  But, I save as EPS in Illustrator and when I do that, then the file is automatically flattened.  This is perhaps what the internet was talking about.
3.  Yes, see number 2 above.  There's no such thing as automatic flattening of TIFFs.  Again, this all depends on the printer and whether or not it can print while retaining original layers.  Some do, some don't.  Most of the time, I edit in PSD with layers intact.  Then, when I prep the file for printing, I will save a copy as a flattened TIFF so the file streamlines through the RIP and Print process.
4.  Makes no difference.  Use 'em if you've got 'em.
Try to get some good resource material at a library or college bookstore or barnes & noble.  Also, get Adobe's Print Publishing Guide.  This is a good reference guide.
Message was edited by: John Danek