Printing from XDP X9 - resolution issues

[gdavidson]

Hi!

It's been a long time since I have had to ask for help

I've got an old problem coming back to haunt me - uncertainties regards printing resolution.

I'm using XDP X9 to print some large and very high resolution prints (70Mpix upwards) with text titles/copyright beneath and on the image itself. Ideally, I'm aiming for the native resolution of the printer which is 720ppi - yes... I'm intentionally going for magnifying glass territory!

Unfortunately, the printed photos coming from Xara looked soft and under a magnifying glass, it was clearly evident that the raster sent to the printer was well below native resolution and looked like 200ppi. Text was pin sharp as would be expected.

From distant past experience, I suspect Xara often treats the photo as being under the influence of a transparency and subject to the transparency setting in Print options>output. Xara was automatically choosing 200dpi and the printed bitmap looked that way too.

Aha! Lets take manual control of the transparency resolution and set it to 720. Okay... 600 is as high as it goes, so I went with that.

However, when printing I noticed a thin black line (with little interruptions here and there) on the left and bottom edge of the bitmap photo. There are actually two identical images on the same page and the interruptions on the black lines were identical on both images on the same printed page.

It also shows up in the printer driver's print preview (Epson 3800 with latest drivers)

The only way I can work around the issue is to select to print as bitmap within Xara's Print options panel. However, that can bring other problems with printers that apply a clear coat on unprinted areas within a photo... (I had a thread running on that subject on 2006!)

To rule out a driver issue, I get the same interrupted line on only one edge if I print to the Microsoft XPS document writer.

I appreciate my use of Xara is perhaps a little unusual but has anyone else noticed spurious black lines around the edge of bitmaps when forcing the "print options" transparency setting to 600dpi?

Also, I'm curious as to why bitmaps become subject to transparency resolution limitations when text is introduced to an image layout.

Cheers!

[mwenz]

Have you tried outputting to PDF, changing the downsampling to off, then printing the PDF?

[gdavidson]

Have you tried outputting to PDF, changing the downsampling to off, then printing the PDF?

Interestingly I had been trying that earlier but was getting PDF files that were blank when loaded in Acrobat. Suspecting I was getting into other issues, I abandoned that route!

However, having tried it again I am able to export PDFs that are working and at high resolution without the artefact lines. Strange.

Thanks for the suggestion. If you hadn't mentioned it, I wouldn't have tried PDF again for a while!

It would be handy to print straight from Xara though

[mwenz]

I almost never print direct from any application. One exception is usually just for quick proofing. For one, I can check for artifacts like you experienced. For another, it is more predictable from Acrobat to printing "on the fly" from an application. If it looks good in the PDF, chances are the printer (if it is capable of the detail) will produce a good quality print.

[gdavidson]

I almost never print direct from any application. One exception is usually just for quick proofing. For one, I can check for artifacts like you experienced. For another, it is more predictable from Acrobat to printing "on the fly" from an application. If it looks good in the PDF, chances are the printer (if it is capable of the detail) will produce a good quality print.

Indeed - with so many different printer interfaces in applications and options within printer drivers themselves, the combination of things that can go wrong are considerable.

[Shakirov]

gdavidson,
try to experiment with these settings:

[handrawn]

whilst like Mike I prefer not to print raster direct from xara, if you do then I second what shakirov said - you must pay attention to those settings, the default is geared to printing from vector

[Albacore]

Very little need to print in A2 but when I had to was given one by work, for the use of, for a few months. Found I had to use PS for soft proofing as reds were a bit in your face, maybe amplifying that slightly, when using xara. Found the options were easy to config, found that paper type was so important to set. Also you can turn off High Speed print and go unidirectional printing which is slower and is supposed to give higher quality printing, don't know if it does. Think I used 1440 dpi for the poster I was doing and it had large bitmap of 2 faces with text and semi transparent background. Again think I tried Adobe RGB 1998 colour in PS and I think this is where Xara falls down as the profile is un-tagged when using the higher resolutions giving a blurry print. I am no expert here but I have wasted enough ink & paper to know that the only info that Xara reads is EXIF data and it needs to recognise but fails to tell what colour space the image was captured in therefore the soft blurry prints. I maybe wrong but I think you need to use PS and get PS to recognise the colour space for higher res. prints certainly that was my finding when using 1440 dpi and set up the config. for Soft Proofing.

[mwenz]

A color profile has nothing to do with imaging quality (softening, aliasing, etc.). Color profiles are only used for consistent color (or not if using multiple, mis-matched color profiles).

Especially when printing to printers using interpolated DPI, such as the high DPI Epson and Canon printers, it is important to understand there are sweet spots in the resolution of the images. This means, typically, using divisible DPIs of their non-interpolated (actual) print resolutions.

[gdavidson]

Thanks Shakirov - that's what I had tried in my original post but it can cause other problems with printers that have a clear ink cartridge - the clear coat can end up in odd places outside the photo area.

I think exporting to PDF may be the way to go. Interesting point, mwenz, about the resolution - I try to aim for 720dpi when printing to the Epson 3800 or 7880 as it appears to be their native resolution when printing at 1440/2880 dpi.

For straight image to paper jobs, Qimage is great for large prints and can apply sharpening to the image at the native printer resolution before it gets sent to the printer, giving the image that little edge. However, as soon as I want to add anything to the print such as text etc, I'm reaching for Xara. It's a shame Xara limits its own bitmap output to 600dpi and in print I think the print-time rescaling to 720 dpi is going to be non optimal.

I even tried Drawplus and PagePlus but both of them have a 64 Mpixel limit!

The next time I print, I'll go the PDF route to see how I get on.

Albacore, you raise an interesting question in my mind - from a colour accuracy stance, does Xara correctly handle colour profiles in photos... My printouts look spot on but they are in sRGB with the printer handling the paper colour profile. If I used Adobe RGB I wonder if things would go awry.

Printing... it can get so very complex!