Transparency and colour

[InvalidBarcode]

I'm using corel X3 at work and i'm needing some help when using BMPs and vector images...it's a bit of a long winded one sorry:

I've created a page divider for a catalogue, the background is a vector shape and is a specific pantone for that section.
I've had to put some graphics over this that are bmp's which i've cut out the backgrounds in corel paint and placed them over the background. When this is exported to pdf it looks fine, but when printed, the pantone showing through the bounding box of where i cut the background out of the bmp is showing through as a much lighter version of that colour.

One way i was told to deal with this was to convert the entire page (except for text and lines) to a BMP, this got rid of this problem as it combined everything together however i recently discovered that this was creating a HUGE unacceptable difference in the bmp's colour when it is printed (became much lighter).

Now, found one way around this was to use the shape tool to outline the seperate bmp's, or powerclip, which worked ok in some cases but say i'm using an image that blends into the background colour like a drop shadow that fades out, or a directional transparency, if i use this i have a solid boarder of where the shape tool box stops, and also the bmp version of the pantone colour with the exact same colour formula is printing as a much lighter colour.

If anyone can help it would be very much appriciated.

 

[attrofy]

It sounds like you are using a bitmap that doesn't have the pantone color of your page divide in its palette. Stated another way, it seems that when your bitmap was "reduced" the color palete was most likely set to adaptive (or it is coming from another source) and has only limited color options to make the bitmap smaller in size. One thing to try, convert the bitmap to 24-bit, as my guess is it is probably some form of 8-bit. Moreover, there may be some conversion issues if the palette being used to create the bitmap is CMYK, and your pantone shades fall just out of scope of the CMYK colors. This is far less likely an option if you are using standard pantone colors, but if you are using some the metalics or other palettes, might be an issue. One other option to try within PhotoPaint is to convert your palette to the same pantone palette you are using in Draw. Along the same lines, make sure there are not issues within your color management that are reducing the color options on export.

I know this may seem a bit out in left field, but my guess is even though the bitmap is cutout, it may be acting as a filter and only allowing the bitmaped colors to print. And anything that passes under the "boundary area" of the bitmap's "virtual border" is getting filtered to meet the bitmaps specs (which is probably lacking that pantone color in the bitmap palette. You could also just try adding that pantone into the palette of the bitmap without making any other changes. This might allow the bitmap to flter that pantone color correctly.

One other option might be to convert the page divider vector into a bitmap - within Draw - then combine the foreground bitmap and the background bitmap into a single bitmap. This also might eliminate any color differences, and also make the color match the rest of the document.

 

[InvalidBarcode]

Hi, sorry for the very late reply.

Thanks but i'm still having the problem with colour.

Bascially what i'm doing is:
Selecting the stuff i want to Bmp
Bitmap > convert to Bitmap
Resolution 300dpi
CMYK 32-bit
Ticks on Apply ICC, Anti-aliasing and transparent background.

Then i am exporting to a pdf.

I also added the pantone i want to my default CMYK palette

Other than these where are the setting for Bitmap colours and what setting would you recommend for output to a cmyk printer? I really have no clue as to what to do and it's stressing me out.

Help is very much appriciated.

 

[Brushman]

Some Pantone colours cannot be reproduced as cmyk and I'm not sure bmp can hold a Pantone colour, if it is for printing on a desktop printer try to use only the cmyk or the rgb colour models.
Alan D