Please tell me it isn't true!

[GerryI]

You are a software developer and I'm guessing you have never worked in the printing industry. While I'm sure it is possible they could "cope" with an RGB file, they often choose not to.

Yes, I am a software developer and it is also true that I have not worked "in" the printing industry. However, I have a lot of experience of the printing process and issues involved as I have been heavily involved with the software side of the printing process for 18 years, both in printer driver development and in application printing code. During those 18 years I have spoken to many, many people who do work in the printing industry and have found very few who actually know what they are talking about. I have had several "arguments" with printing industry professionals about how to do certain things and when I have eventually persuaded them to try something different to their standard workflow (attempting to improve their efficiency or print quality) they have been astounded at the improvements they have seen.

The image conversion itself may not produce the "exact" expected results. Converting an image to "black and white" (B&W) does not produce a true B&W image. There is a slight anti aliasing which always has to be tweaked. When this is done by the printer it adds time to the job, maybe causing delay. Theoretically, the file was provided "as is" and ready to print. Now, the printer has two choices...eat the cost of the fix or charge the client.

Anti-aliasing is a process that reduces the visibility of alliasing artifacts. It has no place in this discussion. The only possible aliasing that can occur when converting an image from RGB to greyscale is in the greyscale intensity values but this should not be an issue. What sort of aliasing are you talking about? What do you mean by "a true B&W image"?

There are plenty of other issues involved that have direct equivalents in colour printing, e.g. the gamma response of the printing process due to dot gain and other factors which vary with different machinery, paper, ink, atmospheric conditions etc. Are these "true black and white" images created for a specific output gamma?

Grayscale conversion poses additional problems. It is very difficult to work with an RGB or CMYK image that "imitates" grayscale, and produce the correct density on press. Again, more tweaking and less predictability...time, money and quality.

Why is it difficult? If you have a 24bit RGB bitmap that only contains greyscale pixel values and an 8bit greyscale bitmap that contains the exact equivalent pixel values, why is one harder to deal with than the other?

And finally, I don't believe many developers understand the importance of "spot color" images. While the images look the same on screen, there is a BIG difference between printing CMYK and spot colors. This is the most difficult fix. Unfortunately, it often requires a complete "rebuild" of the file.

I do understand the importance of spot colours. However, there are serious limitations when using spot colours as lots of the more advanced effects in Designer are only possible in the RGB colour space. The handling of spot colours when exporting to PDF also (currently) has some other limitations.

So to sum it up...Why don't print shops like RGB and CMYK files for B&W, grayscale and spot printing? Costs due to time delays and man power for fixing.

I have found that a lot of print shops are very set in their ways and don't have enough technical knowledge of the process or the tools they use to deviate from those ways.

Gerry

[GerryI]

What type of file are you sending to the printer (PDF, TIFF, PostScript etc)?

Hi Jeb,

Could you answer this question please? From your other posts it sounds like you are trying to send a PDF. Is this a PDFX? Does your document consist purely of spot colours? There are currently limitiations in the handling of contoned bitmaps using spot colours. You may get better (i.e. working) results if you print separations to a file using a postscript driver (preferably one that matches the printer/typesetter used by the printing company) and send the postscript output to the printing company (though they may not be willing or able to handle that).

Gerry

[coza]

Hi Gerry1,

Thank you for the comprehensive information. If I may just ask you one question as a software developer. What does it entail to get to the level of the other so to speak top programmmes when it comes to CMYK handling. What I am really asking - is why can't we work directly with CMYK in the Xara programme without having to pump out a PDF of sorts or some other file to achieve the results we want? - (RGB to CMYK conversion) The annoyance sometimes always seems to be the result of the PDF produced, then having to check the details outside the programme itself, it does not make sense to some users that require that ability. Can you as a developer let us know what has to be done to achieve this?

And yes, you are right about printers, you have to fit in with them, they often don't fit in with you, it seems to be law.

If you would be so kind to answer.

George

[define]

I definitely second this!!

Tks Mike, for the info.

It seems that Xara just assumes everyone who works with the program will print in color - a bad assumption.

In some printing processes, with color they use 4 plates instead of just the one used in black and white - much more expensive to print.

My problem has come in when I have an ad sent with gray scale background and the next month they want to change the text or some other part of the ad.

In Xara, I just use the rectangle tool to mask the old text then use the color picker to match it with the old background. Type in the new text and it is finished. Quick, easy and it looks perfect in Xara and if I print it out on my printer but is totally different shades of gray when I export as a .PDF and then print.

I can take the ad into Adobe and one click and it is a perfect gray scale print but why must one take something that is done in Xara - A LONG TIME GRAPHICS PROGRAM THAT ONE WOULD ASSUME THE END USER MAY HAVE PRINTED - into Adobe to finish the job? Just does not make good common sense to me. - jb