Hi,

Solution/Work-around that yeilds perfect printing again! -Totally I tested stuff for days and now probably have a work-around on the laser-printer raster on raster problem.

On several printes tested I experience rasterisation problems.The printer driver/OSX interprets Blackparts (letters, lines and raster) produced by Calanus+MacPrint as not being solid black or having the slightly wrong resolution.

Today I tested a new thing.
I downloaded the Tiff-print module for calamus.
(The demo is limited to 300dpi so i enlarged the document and raster 200% and printed in B/W raster. Then I used Photshop and set the resolution to 600dpi)
I used photoshop to convert it to 32 bit colour and then added a small colour picture to make the testpage more complex.

1. I printed the new testpage with Photoshop in Colour. The result looked like crap, just like before, the raster was rasterised in random colour patterns. The small colour picture added, looked OK. Just as predicted. -Approximately the same result I would get with MacPrint.

2. I now opened the same testpage into GraphicConverter.
WITH PERFECT PRINT RESULT!!! Each black dot in the raster is perfectly reproduced with no added effects. The colour picture looks PERFECT too.

May I add that GraphicConverter is a cheap, but great Shareware program!
This is a worksaround that I will use from now on. I just have to buy the print to tiff-print module first.

So what we are seeing here is probably imperfections and approximations in the OSX printing system. Imperfections that some software- and printer-driver makers knows how to get past.

If the the makers of MacPrint are interested I have slightly more detailed information for them, from my testings, that I will be happy to share.

Roger:
Did you simply open the TIFPrint produced TIF in GraphicConverter?
Or did you open the Photoshop enhanced CMYK TIF in GraphicConverter?

Did you convert the TIF stuff to another color depth somehow in GraphicConverter before you started printing?



Grüße / Greetings / Groetjes / Salutations,
Ulf Dunkel · invers Software

Ulfid you simply open the TIFPrint produced TIF in GraphicConverter?

Roger:Yes, the only thing I do is to change the resolution to 600dpi.

(As I described earlier I made my cdk twice as large and the raster half resolution to simulate 600dpi, because of the TIFPrint demo limitation to 300dpi and then set the resolution right to 600 in GraphicConverter)

Ulf:Or did you open the Photoshop enhanced CMYK TIF in GraphicConverter?

Roger:I actually made an RGB(!) conversion in photoshop to be able to paste a colour photo onto the cdk-tiff for further testing, which was also sucessful. I wanted to see if the driver and printer reacted differently to a mixed source with both B/W and full colour parts.

Ulfid you convert the TIF stuff to another color depth somehow in GraphicConverter before you started printing?

Roger:-No not for the first test, which was also sucessful!
G.C. says that the TIFPrint tiff is 1-bit and it detects my photoshop test image correctly as being 24bit colour.

New test: If I take the good-looking rasterised tiff (600dpi) and import it into calamus at ("optimize frame size for printer", 600dpi) and then une "print to pdf" with the printer/driver I see a skipped lines indicating that lines are skipped here and there (mismatching resolutions.
If I print the "print to pdf"-file with GraphicConverter, I get no re-rasterisation, but I get a few brighter bands and sometimes thin stripes in the raster, due to what I guess is a resolution mis match.

If it wasn't for this issue I could simply just print to pdf and then print to paper with GraphicConverter. It looks much better than printing with MacPrintX since there is no re-rasterisation, but the skipped lines makes it not perfect enough.

If there is some conversion to pdf somewhere along the way from MacPrintX and the printer, it is probably a strong bet that the problem is created there. Viewing B/W material ran through print to pdf, in many programs, I find that perfectly black pixels has grey outlines when zooming in closely. (this is true even in G.C.) If this "pdf-engine" is involved in printing, maybe it is causing the problem. Maybe this is a function that can be turned of... -Just guessing...

Roger Jönsson wrote:

> (As I described earlier I made my cdk twice as large and the
> raster half resolution to simulate 600dpi, because of the
> TIFPrint demo limitation to 300dpi and then set the resolution
> right to 600 in GraphicConverter)

btw: Did you realize that there is no 300 dpi limit in the demo version? The only limitation of the demo: It spreads invers logos all over the printed page.


> Roger:I actually made an RGB(!) conversion in photoshop to be
> able to paste a colour photo onto the cdk-tiff for further
> testing, which was also sucessful. I wanted to see if the
> driver and printer reacted differently to a mixed source with
> both B/W and full colour parts.

Did you check what happens if you keep the TIF in CMYK state? (You could e.g. convert your colour photo to CMYK first and merge it afterwards.)


> G.C. says that the TIFPrint tiff is 1-bit and it detects my
> photoshop test image correctly as being 24bit colour.

You can set the colour depth of the TIFPrint output to other depths in the parameters dialog. Simply click on the upper right button in the Calamus Print dialog.

There must be some kind of misunderstanding in the print stuff queue. TIFPrint delivered a simple 1-bit TIF file via MacPrintX to the MacOS printing system, which then handles the data over to your appropriate printer driver. Somewhere inbetween must be the re-rasterization. You can try if MacPrintX is to be blamed. Simply switch off the Calamus raster generator (by removing it from the list of loaded modules) and see what happens.

I guess it's somewhere in the MacOS printing system. I would bet that it depends on your native MacOS printer setup.



Grüße / Greetings / Groetjes / Salutations,
Ulf Dunkel · invers Software

Ahh. The resolution setting is at the side, not like MacPrintX.

I tried printing th A4 page to 600dpi.
ARRRGGGG. Now I get the darn re-rasteration with GraphicConverter too. I cut the page into half then it looks right.
It must be the result of some sort of compression! The XeroX6100dn printer has 64Mb memory.

(I tried printing an A5 with MacPrintX. I get the terrible re-rasteration. So there is a difference comppared to G.C. Maybe it always makes a page larger than A5...)

I then Tried running GraphicConverter in OS9 Classic mode. The full A4page is printed 100% correctly!!!! (tried B/W, greyscale and colour) The cdk prints faster in classic even though I am using the slower USB connection as opposite to the network connection i OSX.

So what we are seing here is OSX unintelligent printer compression?
Even a full A4 page in 8bit greyscale should fit in half the memory of the Xerox. Can it be so that OSX print system always thinks CMYK and at least 140Mb is needed to process, unless the printer driver overruns this stupid process? No wonder the printing in OSX is so darn slow. Is there a way to override the compression?

My friend who tried the printing the B/W cdk on the Samsung 550n (same physical printer but with more memory and postscript) could print correlcly in greyscale, but not with the printer set to colour. The printer has 128Mb. Maybe with more memory it could handle it... -This is absolutely crasy!

On OS9 I could print exactly this page and the same resolution correctly with a 4Mb OKI laser.

Another strange thing is the after having raised the contrast in my B/W OKI printer the re-rasterisation is gone and it looks nice (OSX). This printer doesn't have more than 8Mb memory...

It seems that OSX always think uncompressed CMYK and adds antialias, because it assumes the printer will need it to be able to compress or better rasterise the document. If so it is really, really lousy, since the result is slower printing and larger document and in many cases destryed quality.

Unfortunately no one has answered my request for suggestions on affordable Colour Lasers that do work properly with this type of graphics on OSX.

The solution for me is either TIFPrint + GraphicConverter in Classic mode or a new ColourLaser with 256Mb memory, it seems.

Ulf: should I start a new subject with this message to avoid mis-leading others.Those who do not read from start to finish?
Or should we leave it here for now?