Greyscale images print in colour mode

[philcam]

Just got a new Toshiba 451 office laser printer which autoselects colour or mono print depending on the image on each page. GREYSCALE IMAGES print in COLOUR MODE, which is very expensive. Anyone know how to fix this? Does DUOTONE create an image that will be sent as mono? Or do I have to go to (bad looking) 2 bit mode with dot patterns?

Thanks

Phil

 

[javabearSTL]

By "greyscale images", what exactly are you referring to? Bitmaps? Vectors? Both? What version of Draw are you using? Duotones... well, that depends. Are you using a PP-created duotone in the CPT format? If you're working in a file that is using an RGB or CMYK workspace, did you go to the Print dialog box and choose the "all colors as greyscale" option on the Misc tab?

 

[philcam]

Thanks for taking the time to answer.

I am referring to Bitmaps. I'm using Corel 12. When I reduce colour images to greyscale, they remain in CMYK, and so trigger a "color" print on the printer. My goal is to have - for example - a colour pic on the front of an 8 page booklet, but images inside in (cheaper) mono. If I choose "all colours as greyscale," then I imagine I lose the front cover colour as well? Duotone has the same problem it seems.

Phil

 

[javabearSTL]

Um, "Corel" is a company, not a product. So are you referring to Draw or Photopaint? People often post in the wrong area, so unless you specify which product, others may refrain from responding because you haven't given enough detail for them to form a good answer.

You didn't answer the question about the Duotone(s) re: whether or not it's a duotone in the CPT format or not.

It's unclear as to whether or not you're actually saving the bitmaps as greyscale images or if you're just desaturating them.

 

[philcam]

Gee, sorry. I came to the Corel DRAW forum for a reason
I am using Corel DRAW, as you assumed in your original reply to me. I'm creating duotones, and converting to greyscale, in the "bitmap" menu of Corel Draw ie Convert to Bitmap > Greyscale. Usually, I'm importing a full colour jpeg image, for instance from a digital camera. Likewise, I tried creating duotones or monotones (using BLACK as the chosen colour.) No matter what I do, though, I can't convince Corel to print it as a true greyscale image on the laser printer. (ie using only black toner, rather than a combination of the colour toners.) The resulting "greyscale" image has a slightly blue hue. So, do you think if I convert the image to greyscale OUTSIDE Corel Draw, it may help?

 

[Brushman]

I get the same thing with my Epson 2100 inkjet but it is more on the magenta side. If you go to print preview and separate is there just the black showing as present? if yes then it is greyscale and would print that way if going to an imagesetter for output - try separating the black plate to your laser. I suspect it may have as much to do with the print driver as Corel Draw.
Alan

 

[philcam]

Separating the black plate to the laser" may work fine - but it's hardly convenient if you just want to click and print with a mix of colour and mono pages! There must be an easier way to create genuine greyscales??

Phil

 

[javabearSTL]

I wouldn't do this in Draw since you're working with a bitmap. I'd use Photopaint. Just do an Image/Convert to duotone, choose your pantone colors, do whatever else tweaking you want, and *save it as a CPT* file. (you don't want to save it as a JPG since JPG is a lossy format.

Import the CPT into Draw and the PMS colors will separate to their proper plates (if you look in print preview).

The "printer" you referenced is technically a copier (as that is how Toshiba markets it) and while it does do color, it only does CMYK and not PMS, so all PMS colors have to be mixed down to CMYK values. So if you're trying to print it all on this printer, it doesn't really help you to change anything to PMS colors.

If you're sending this out of the office for professional printing, just do as I mentioned above and then publish a PDF of the file and the service bureau will have the tools to print you mono/duo/tri/quadtone image in PMS values.

If you're really only wanting to print in b/w, just take the photo into Photopaint and save it as an 8-bit greyscale image and then bring it into Draw. At that point it will only use the black toner.

Of course there's always the option when you print to go to the Print dialog box and on the MISC tab there is a radio button to print "all colors as greyscale" and then you don't have to do any color conversion.

 

[philcam]

I'll try the export-import thing with Photopaint... but Corel Draw also offers to convert to 8-bit greyscale, which is exactly what I did. I know I can print "all colors as greyscale" - but my original point was, the copier feature-list promised "mixed mode" that would auto-detect the content of the page and print in the correct mode. That's useful if - as I do - you want to splash some colour on the cover page and keep the inside pages greyscale. I could just as easily do "All colors as greyscale" by using a mono print driver.

Phil