I am going crazy with this issue and really will appreciate any help I can get.
So this problem occurs only with raster files (vectors are fine) and only with some digital printers (offset is fine). All the sheet music is written by the client in some specialist software and afterwards exported to .jpg/.tif files. On screen everything looks great and the colors are even. Yet after printing, the music examples look “spotty”, “wavy”, like this:
All the files are 300 dpi, grayscale, .jpg or .tif format and I am making sure that all the blacks are as black as can be :). So the problem does not seem to be a result of poor reproduction of halftones (or at least, not only). Is it resulting from a lower screen ruling of digital print (when compared to offset print)? And if so, how do I combat it? Will using a higher resolution files (like 1200 dpi) help?
I can of course just redraw all the music as vectors/ask the client to export .eps files and avoid the problem altogether. But that is not always an option. And, as this is not the first time I encounter this issue, I would really want to understand how the problem appears and how to solve it (if at all possible).
You seem knowledgeable enough to know that vectors are the correct vehicle for this content, and raster images should be a last resort, so:
Why is it not always an option? What about PDF? What platform does that notation software run on? If it’s Windows, printing vectors to PDF is likely possible, even if direct export is not available.
Once those pages are committed to a raster format (i.e., destroyed), there’s no universal fix for your problem. The true fix is to prevent the problem by preventing rasterization.
Thanks for your response. I do know that vectors are a correct answer here. Most of the time I can get vector pdfs or eps, or even draw them myself. Sadly, that is not always an option because of a specific client situation.
For example, with one book there was a situation where musical examples were written for the author by somebody years earlier, exported to jpgs and given that way. There was no way to get hold of that somebody to ask for pdfs (or eps etc.), nobody wanted to pay to have to examples written up again and there were waaaaay to many of them for me to just redraw them for free, for the good of the book.
So it’s not about software limitations or me searching for some magical ways of reverting raster back to vector ;). I am just trying to figure out what exactly causes the problem with rasterized music in this specific situation, if I am missing something and there is a way I could prepare rasterized musical files to avoid that problem. My currect guess is that it’s a fault of a low screen ruling of those certain printing machines (as not all digital print machines produce that problem and some printing houses handle the raster just fine) and there is just nothing to be done.
And from your response, I guess I am at least right about the “there is nothing to be done” part.
Do you only have the problem with certain printing houses?
Or does it happen sporadically across several print houses.
What layout program are you using?
I’ve seen an issue like this in Quark, where the image had been enlarged within the file and the print tech did not tell Quark to send ALL the image data.
The problem exists only with certain printing houses.
I am using InDesign for layout and Photoshop/Illustrator for image work. All the images I always prepare properly in Photoshop/Illustrator (in a proper end resolution for the size they will be in print, proper color-space etc.) and never let InDesign tamper with them when generating pdfs (no downsampling, no color changes and so on).
And in the meantime my question has been answered successfully by pixxxel schubser on Adobe forums. So thanks everybody for input :).
And for those interested: it is indeed a problem with those concrete digital printing machines and their capabilities in the context of those files. I quote: “Some digital printers does not have more than 300 dpi resolution and does often resample your file. And that is much to low for a pure black rasterized lines with 0.5 pt line width.”
When it comes to dedicated black and white digital presses, the way an image can be produced, varies greatly from one manufacturer to another. Machines for quite some time (some still do) used a technology where toner has to “celled”. This simplistic technology involved toner either being present in an area, or not present. Creating a halftone, gradient, or long, fine lines (your music sheet) was a challenge, if not impossible.
New super cell technology allows for a Black and White machine to print equally as well as their color counterparts. Or in some cases, like in the case of this Canon (Oce) Vario sample I just shot at my desk, print even better.
It might since 300ppi is a good resolution for halftones (twice the halftone screen frequency of 150lpi). It’s not a great resolution for line art. The output resolution of many digital printers are much greater than 300dpi, so a higher-resolution file might solve some of the problem.
However if you’re able to request higher-resolution files, why can’t you also request vector art, as in a PDF, maybe? Also, you mentioned JPEG, which is a lossy compression algorithm, which will degrade the quality of your line art even further.
My question if higher resolution would help was purely theoretical. May goal with this topic was not to seek help with some specific situation but to understand why this problem happens at all, why specifically to music sheet files and so on.
And now I know
And the same problem happens if the providedraster files are .tif (without compression or with lzw compression). So .jpg compression is not at fault here.
