In this topic you will find quick tips and links to useful information on avoiding potential PostScript file issues, transparency issues, information on using ONYX PostScript RIP options, as well as guidelines for creating PDF files for wide-format printing.
Tips on avoiding PostScript file issuesBecause of the many ways elements can be combined in the creation applications, a PostScript RIP file can handle the instructions provided in a PDF or EPS file in many different ways. To avoid potential PostScript file issues, we recommend the following:
- If you are using a CMYK (or CMYK plus light ink) printer, then a PDF workflow is best.
- This will allow you to take advantage of the many transparent effects in current design applications.
- This will also work well with spot color workflow.
- Use a CMYK blending space when creating the transparent elements.
- Always use a CMYK colorspace for the document mode.
- Always convert every element to a CMYK colorspace during the creation process.
- Color management settings should have the same rendering intents for image and vector elements.
- EPS does not support transparent functions, which means that if you save the file as an EPS it will flatten the elements. This also means the RIP does not have to process transparent elements or use blending spaces to render the element.
- This is a good alternate workflow for when problems arise, or if you are using a printer with expanded gamut inks, such as CMYKOG, CMYKRGB, etc. Because this eliminates very complex blending space processes.
- Always use a CMYK colorspace for the document mode.
- Always convert every element to a CMYK colorspace during the creation process.
- Color management settings should have the same rendering intents for image and vector element.
NOTE: Converting to EPS may also cause problems with some elements that are not supported in EPS. Be very careful with this workflow.
- It may be necessary to turn off the Spot color replacement table. Spot colors that are by themselves should work fine, but spot color elements that overlap or are rasterized may not render the same.
- Some values have changed to optimize processing, such as MALLOCPAGES
- Some settings are no longer needed, such as FIXSPOTTRANS
- We recommend leaving the settings the patch sets unless a specific need requires a change, like enabling overprint for files that were designed to use overprint.
NOTE: Overprint workflow should be used without color management enabled (all profiles off). Color management can change the mix of inks used thus changing overprint functionality.
TIP: To learn more about overprint, see this Max-imize article
The ONYX PostScript RIP engine is incredibly powerful. To simplify your use of the PostScript RIP capabilities, we would like to highlight the following workflow options:
SPOTRENDERINTENT- Use this option if you want to change the rendering intent used for out of gamut spot colors (0 = Perceptual, 1 = Absolute, 2 = Relative, 3 = Saturation, and 4 = Postercolor)
BLACKOVERPRINT- This option allows you to use overprint instead of knockout for only black elements.
BANDHOME - Change the temporary swap workspace of the RIP. This may increase performance as it can move some processing to a separate hard drive.
OVERPRINT- This option overprints all channels instead of applying a knockout function when combining separation.
USEPDFCROP - This option tells the RIP to use the PDF Crop box from within the image.
USECUTSPLINES - This will turn off the splines function for cutters. Use this if you are seeing stray lines in your cut data.
These and other PostScript Options will help you get the output you are expecting. To learn more, click here.
PDF Files are complex and issues can appear during printing that are not visible in digital format. To help you avoid potential issues, we have put together simple guidelines for creating a PDF-file that is compatible with large-format printing:
- If your graphics application has presets for saving PDF file in PDF/X format, choose PDF/X-4. If not, save files as PDF version 1.6.
- Embed your images. TIFF files are recommended. Avoid using lossy formats, such as GIF or JPG.
- Use high resolution images (image resolution should be greater than 150 dpi, but no higher than 600 dpi)
- Avoid embedding 16-bit images. Convert 16-bit images to 8-bit before adding them.
- If your design application allows you to define a bleed area, the BleedBox must be larger than the ArtBox, but smaller than the MediaBox.
- Embed all color profiles in your PDF file.
- Embed all fonts in your PDF file.
- Do not embed non-printable items such as movies and audio.
- Place annotations outside the ArtBox or remove them prior to saving.
- Do not use encryption when saving your PDF file.
To download a PDF file with guidelines and learn about Color Spaces in PDFs, please click here
- Have your design application convert all elements to the current working space. In the Adobe Suite these settings can be found under the Edit menu > Color Settings
- If you are using spot colors and transparency, do not use EPS or PS. These file types do not support transparency and are rasterized. If your spot color crosses the transparency boxes in your file, they will be rasterized if saved as an EPS or PS file. You can only resolve this by turning off the color matching table or using a PDF file format. If you use the virtual printer workflow to submit jobs to your ONYX RIP-Queue, these files are postscript files. All transparency elements are rasterized.
- PDF files version 1.4 or higher do support transparency. If you use PDF/X-1 or save your file as a version 1.3 PDF, all transparencies are processed and rasterized when they are created. It is recommended that you use the latest PDF version, 1.7 if your design application gives you that option.
- Your ONYX RIP software has the ability to see input profiles within images, if embedded. This can help improve workflow and make color management much easier. You can embed profiles into TIF and PDF files. EPS, PS and others do not support this ability.
TIP: For information on troubleshooting transparency problems, see this Max-imize article