Digital BW, The Print

lulalake_1999 wrote:
> 
> Hmmmm. I don't know but I had a oddly similar situation. I was 
> printing a sheet of 3x5 Christmas shots of my little girl for 
> relatives/cards etc. when I noticed a black line about one or two 
> pixels wide where the "smile crevice" is between her nose and the 
> cheek. This line didn't exist in the pic.
> 
> What I found was this. I was printing from a rather large file, about 
> 5400x3700 .PSD and not downsizing for the picture, simply resizing in 
> the print preview. When I downsized, then printed, it went away.
> 
> Could you have sizing/interpolation issues?
> 
> Jules


It is almost Christmas, can't be misplaced holy halo's, could it?

No kidding, most likely interpolation artifacts in the RIP or 
driver.  So interpolating the image to 360 PPI or 720 PPI, 
depending on what the driver's native resolution is will take out 
further interpolation in the driver/RIP and you can check on the 
monitor whether those circles exist in the image before it gets 
printed. If they appear you can spot them out. Use it when a 
thing like that happens.

There's an interesting parallel with Qimage of some months ago, 
the upscaling in Qimage has been very good for a long time but 
the downscaling was far more crude, anti-aliasing could be better 
for example. That showed in image conversions for the web. On 
request of Bart van der Wolf work was done by Mike to improve the 
downscaling and it is now much better than before. See:



<http://www.xs4all.nl/~bvdwolf/main/foto/down_sample/down_sample.htm>

<http://www.xs4all.nl/~bvdwolf/main/foto/down_sample/example1.htm>


The first url shows circle targets for the test, couldn't be more 
appropriate.


A far weirder problem occurred some years ago when a friend with 
some 9000s got Athlon CPU's with the first VIA chip motherboards. 
  Randomly placed ovals with lighter tones in the prints. Same 
images, software but Pentium systems didn't have it. He returned 
the motherboards. There was some analogy to sound problems with 
those motherboards but it never became clear what was going on.

Ernst