[Guest]

I have a simple, but technical question I'd appreciate advice on. For the purposes of the question, I have simplified the numbers.



My commercial printers are going to print pages I have prepared, at 12 x 12 at 300dpi and have asked that I supply these page at 300dpi to this dimension. For various reasons, my pages are going to be created as 12.2 x 12.2 at 300dpi - the dpi I can alter, the page size I can't.



So if I just supply these as is, I expect they will need to resize/resample from my 12.2 x 12.2 300dpi images before printing them at 12 x 12 300dpi.



Assuming that to be the case, is it better then, for me to produce the 13 x 13 images at a much higher dpi (say for example 600dpi), so that there is more data in the image for them to resample down to? In which case, how would I go about working out what the best dpi setting is to create my artwork?



As stated above, for various reasons, I cannot control the physical size of the image outputted from my workflow, but I can dictate what dpi it produces it at.



Many thanks in advance.

[wim]

I would say, the higher the dpi the better. I am a bit amazed they actually ask such a question, basically because they can very easily scale it down themselves, I would think, as long as it is at least the size and dpi they seem to require.



However, maybe this is about image size, and don't they want anything larger than a 3600 pixels X 3600 pixels image.



Personally, I would ask the why, how and what.



I don't understand why your 12.2 x 12.2 images couldn't be resized to 12 x 12 either, BTW. We are talking digital after all, and only requires a rather simple change in resizing settings, whether this is part of a current workflow or not.



HTH, kind regards, Wim

[netrex]

To be pedantic, you mean PPI.

[Brightcolours]

Most printers, including professional ones, have NO clue why they are always thinking in "300dpi". Usually it is just nonsense, and they can just place an image of whatever resolution in the software they use and let the software worry about scaling.



The 300DPI usually is not based on anything, just dates from when laser printers actually printed at 300DPI. Black dots per inch.

[Guest]

Thanks to all for the insights. Apologies, I think in my attempt to get to an answer quickly, I over-simplified the context info.



Basically what it is is that I'm using LR4 and need to get my book that's design in LR4's book module to my printers. They use their own proprietary software and have guidelines that say I can design each page layout myself in an external package (e.g. Photoshop) so long as I follow the guidelines in terms of page size and dpi (agreed, they actually mean ppi really). So the task was to get my LR4 Book Module to export in an appropriate format and resolution, such that when each page was reimported to the printer's own software, there was sufficient detail for it to resample/rescale as necessary.



I was assuming that they just print at 300dpi hence the (implied) stipulation for 300ppi images. But as my export from LR4 is not EXACTLY (its close, but not exactly) the same size as their pages that they print, I know some resampling/resizing is inevitable. Hence, the simple example given in my original post.



Since raising this question, Adobe has release LR4.1 which happens to export directly to JPG and not PDF. This simplifies my workflow as I no longer need to extract the JPGs from the PDF. So based on this and the advice above, I think I will export everything at 100% quality JPGs, at 600dpi - I think that should be ample for the printers?





Thanks once again all.

[dave9t5]

I think 300"dpi"/ppi is just the traditional recommended minimum?



Back in the earlier days of digital processing, I think it was more common for customers to have created low-rez files that looked good on small low-rez monitors send them to the printers and get disappointed when the same images looked horrible printed. At the same time, higher rez files were unwieldy to email/FTP and perhaps process based on the servers, connection speeds and workstation technology at the time.