Expert: LizaL - 3/1/2005

Question
I designed a color poster in CorelDraw using photos scanned in to Photoshop cs.  I had to manipulate them, placing figures in front of a crowd.  Since this was going by email to India the pictures used were taken there and were not too great.  I lightened, color corrected, added saturation and unsharp filter after getting the result I needed.  I saved it to a psd to preserve the layers and then to a jpg(high) to import into CorelDraw.  The poster was 24"x24" and so the photos were fairly large and 300 dpi each.  Since the completed file was so large I started lowering the resolution to 200 dpi and compressing the photos more (medium jpg).  If it weren't that I had to email them, the size of file would not be as important.  Will the printing by the printer be clear enough at that resolution and compression?  I don't know what method or printer is being used.

Answer
Hi Linda,

You sound like you've covered all your bases, and done everything you possibly can, on your end. But the truth of the matter is, if you don't know what method of printing is being used, or what type of press or printer will be doing the job, all you can do is the job that you did -- and it sounds like it was the best possible job -- and hope for the best. Without that information, and especially without my seeing the job itself, it's impossible for me to predict how it will print.


Don't get me wrong, you sound like you were very thorough. But there are some things you can do before a print job in order to ensure good quality. If it's not possible to do them this time, maybe you can employ these things the next time around.

But without my knowing the type of press, the method of printing, or the paper being used, it's just impossible for me to say what will happen!

Here are some tips, though, when it comes to dealing with printing jobs, especially offset jobs:

1. As I mentioned, it's always best before a print job to know the type of press being used (if being printed offset), the method of printing (i.e., web offset, offset), and the paper being used.

For instance, if a job is to be printed for a newspaper, traditionally newspapers (which print web offset) require at least an 85 linescreen (lpi). So your images should all be at least double that amount in terms of resolution -- 170 dpi and above.

Other presses and types of printing require different file formats, different resolutions -- so it's always best to get clear on this *before* you start any type of print job.


2. You said you lowered the resolution and that might work out, depending on the paper and the printing method being used. But without knowing that, I can't really say what will happen. Bear in mind that when having a job commercially printed, that job is always subject to "dot gain." In a nutshell, that means that the ink sort of swells when it's applied to the paper -- and the more porous the paper, the more the dot gain (newspapers, printed on newsprint, are notorious for this!).

So if you know ahead of time the paper you're printing on, you'll know how best to sharpen your graphics and type, and keep dot gain to a minimum.


3. One thing you might try if it's not too late is using the 300dpi pictures, and then compressing the file as a .zip file. You can do this with either a Mac or PC, using Stuffit or WinZip. That will "stuff" your file, but when the file is unstuffed on the receiving end, it won't have suffered in quality.

Or, if it's possible, can you upload the high-res, uncompressed job to a server and let the receiving party download it from there? That's pretty much a no-fail operation, since you wouldn't have to compress the job beforehand.



4. Ask for a proof before the job is printed. If at all possible, request some form of proof before the job goes to press. Then you can make any changes you need to make to head off any problems.


5. Finally, always before undertaking any kind of job that will be printed, especially commercially, and distributed, ask the production manager exactly what you, the designer, will need to do. Ask about the printing method, the paper, the type of press that will be used -- ask what file format they need the files in, and the resolution of all images, both vector graphics and photographs. Ask about the best delivery method -- CD? Download from an FTP site? Email? And ask for a proof prior to printing.


I hope this helps! Let me know how it turns out.

Lisa