how do I print halftones to be sent to a printer.

[drk52]

Hi, I am trying to get a newsletter sent to a printer.
I have some pictures in it, and I want them to look good, and the output to be "camera ready". I would like to apply a screen (150 dpi?) to the graphics, but I am unable to get them to print in a "screen".

How do I convert them to halftones? Do I have to have a post-script printer?

 

[zefir]

drk:
Case A: the printer is the Print&Pressman
In this case use CMYK images. The conversion
to rastered images (rendering) is done in the
imagesetter.
RGB-CMYK conversion is done by PhotoShop,
using the final print profile. Don´t embed the profile.
In PM the same or a similar profile
has to be selected for the correct preview.

Case B: the printer is a local Inkjet.
Use RGB images. The rendering is done by the printer
driver, but for inkjets by dithering (clouds of drops).

Case C: the printer is a local Laser.
Use RGB images. The rendering is done by the printer
driver. Use highest resolution in dpi and the default
"screen" angles and frequency in Lpi.
Hope this helps --Gernot

 

[zefir]

drk: I had assumed, that your images are TIFF or BMP.
If they are EPS or PDF then this will not work satisfying
on a non-Postscript printer. PCL printers print the preview,
not the accurate file. ---Gernot

 

[drk52]

Thanx zepir, and sorry I was kinda vague. I know what I'm trying to do, so I guess I expect everone else to know it too.. Ok, the printer is a lexmark 5700 inkjet (no post-script capability). the files are originally Jpg, but can be made into whatever works best really. The files are all black (no color). What I've been doing is screening them in photoshop, and then placing them as a bitmap into the PageMaker text file. That works Ok I guess (not terriffic), but seems kinda like a lot to go through if there is a faster way.

Would I want to use the RBG rendering even for black color? And does the "dithering" reproduce well at the Print shop I want to eventually take it to?? (this is eventually to be sent to a printer (print shop type printer).

 

[carlow]

Hi,

A printer whatever it is has in his hardware and software some screenings. For example a Postcript printer of 300 dpi has a built-in screen of about 65 lpi. Every printer is limited to some degree. If you try to print a postcript file (all pm-files are postcript) to a pcl printer which doesn't use a sreen but try's to interpolate the postcript file and put some points in between grey's or colors so that the result will look almost the same as the postcript printer as far as the capabilities. It has no use to apply screening in Photoshop or whatever other programm. You should make your pictures like yu wan't them to appear in your final result. Place them in PM and then the hardware of the printer takes over when you wan't to print. Be sure that your image file has enough dpi's so that when printed to a pro printer the result will be as good as the printer allows.
So far for the tech info. If you wan't to have a good printing result on your pcl printer you can look for a postcript emulator for your printer. This piece of software will translate the PM postcriptfile to an appropriate file that is optimized for your pcl printer.

Hope this explains it somewhat
grillhouse

 

[zefir]

drk: for your printer it´s NOT useful to convert to
1bit per pixel bitmap in PhS.
If the image is Grayscale, than it´s packed Indexed Color Gray
and any printer (the machine) will do the rendering and the
printing by K=black-ink-ONLY.
"Rendering" means:
For Inkjet: find the appropriate cloud of black dots.
For Laser: find the appropriate size of black dots in the Lpi raster.
Altogether: the user hasn´t to take any care about the rendering.
This is done by the printer (PostScript) or printer driver.
--Gernot

 

[drk52]

Hey thanx a whole lot you guys,...!!
Grillhouse and zefir--really, I mean it.
It's really great of you to help, and I'm sure your responses are enlightening, or at least they will be when I assimilate it all...

I do think this helps, and I have really learned a lot.

Basically, you are saying, let the printer do the screening --though I may need a PS interpreter program.

I'm sure with a little more trial and error, I'll get it right now. Thanx again..