7D Raw to TIFF

[adam z]

After processing my 7D RAW files using DPP and I go to process them as 16 bit TIFFs, I am confused as to the best setting. Using Lightroom in the past with my 30D files, when exporting files as TIFFs I would always export as 300ppi (this was what came up automatically in LR, and it seems to be a standard). With the 7D files, DPP automatically comes up with 350ppi. I don't know if it is pest to leave it at 350ppi or change it down to 300ppi. I am assuming that it is best to leave it at 350ppi, however I don't like making decisions without knowing why I am making them.

What I am asking is am I best off converting the processed RAW files as a 300 or 350ppi TIFF, and why??? Does anyone know if this difference is related to the differing cameras, or the software. I have never really heard about ppi over 300.

Thanks in advance

Adam


ps: The attached image was converted to a 350ppi 16bit TIFF in DPP, and had a few minor tweaks in LR (but will be done properly in Photoshop when I get the chance). I know it's not a fantastic shot, but there is something about it that I like. Obviously it was downsized for web use.

[Slobodan Blagojevic]

... What I am asking is am I best off converting the processed RAW files as a 300 or 350ppi TIFF, and why??? Does anyone know if this difference is related to the differing cameras, or the software. I have never really heard about ppi over 300...

Taken in itself, the output resolution setting is totally irrelevant, so whether you use 350 or 300 (or any other number between 1 and 60,000 dpi the DPP allows) makes no difference whatsoever. It only matters in combination with the Resize setting, and even then only if you choose a measuring unit different than pixel. In other words, it only matters if you want to change the size of the original file.

[adam z]

Slobodan, thanks for replying. Sorry, but I'm not sure I quite understand. If it doesn't matter why is it an option unless you are resizing. I am sure it would have to make some difference if I was to select say, 72ppi and then tried to print big - wouldn't it?

I am assuming either I posted this in the wrong spot or other people read what you wrote and think it was an adequate answer. Unfortunately for me, they are probably farmiliar with what you are talking about and it makes sense to them, but I need it "dumbed down" a little - or at least a bit more explanation on the "why" it doesn't matter to help me understand.  

Anyone!

[Slobodan Blagojevic]

... Anyone!

It's me again, sorry  

... I am sure it would have to make some difference if I was to select say, 72ppi and then tried to print big - wouldn't it?

As with most things in life, the answer is: it depends.   If you select 72 ppi, move it to Photoshop and immediately go to File>Print>Print... yes, there will be a difference: the print will be just a small section of the huge image (7D files @ 72 ppi result in a 48" x  72" printout... if your default page setup is Legal size paper, i.e., 8.5" x 11", you would have only 2-3 % of the image printed. Similar thing would happen if you insert an image in programs like Word: images with differently saved Output resolution (say one @ 72 ppi and another @ 600 ppi) would have different sizes on the page. However, no self-respecting Photoshop user would do such thing (i.e., open file and go File>Print>Print) without checking first the file size, desired print dimensions and output resolution. In such a case, the output resolution embedded by DPP (or any other converter) is indeed irrelevant, as you can (and should) always check it and change it accordingly.

Simply saving a file at different output resolutions does not change anything in the quality of the file, which is determined only by its pixel dimensions and not by the embedded output resolution.