As I am intrigued with the conditions you set in your request, I try to analyze what your goal is.
Thanks for chiming in, it's well appreciated!
I am printing plans for private table-top gaming where only part of the plan is revealed during a game. So printing the whole large plan would reveal all at once (and need a larger printer) and printing poster-tiles would cut the content at the wrong parts. Think of splitting a large architectural CAD drawing into smaller DIN A4 part where the rooms on the drawing dictate where to crop each smaller print. Also think about 300 g/m² photo-quality paper costing next to nothing compared to bigger paper. I do sometimes use A3 and A2, but rather occasionally.
The resampling method you selected is a good one, it has been discussed here often enough. Pity that the software has not printer interface to do that on the fly with a print job.
Well, the printer does resample to its native DPI on the fly, but likely only using something easily calculated such as bilinear.
The original images I am printing out include grid-lines that are supposed to be 1 inch apart, but the source images are smaller than the output size and even compressed (usually being part of a PDF). I used Photoshop's resampling in the past, but Gigapixel AI (up to version 4.2.2) is perfect for these artificial plans and invents lots of useful details (plus perfectly rounding aliased lines). Just another function of Photoshop that I do *not* use anymore thanks to Gigapixel. I resize to the destination size and DPI (360 for the Epson, 300 for my HP color laserprinter) and then print at that native DPI to keep the print driver out of the resampling pipeline.
You can not use two image halves, less than 1 GB each, so Qimage Ultimate could cope with the image size and proof parts to A4+ or as an alternative several proof parts on a larger sheet?
That would kind of be possible, but quite a hassle. Not only because it involved extra steps, but also because the halves would likely cut right through image content that I need on a single sheet of paper. Just loading one huge image into the software and then starting the print dialog to manually select the crop really is a big time-saver (albeit somewhat buggy in PS).
QU has some proofing methods that allows selected parts to be printed while it keeps the image files intact.
No proofing necessary, just printing silly gaming material to lay out on a table and put miniature gaming figures on. This is why I wrote about "abusing" Photoshop. I really pay for this much bigger software just to print this stuff. Additionally I do have much use for Lightroom, but find that alternatives are getting more and more viable, like using Mylio for its much better face detection.
I never use borderless as I find it far more reliable to use a larger paper and cut back to the sizes I need, ending with a borderless print or with exact border dimensions that are not set by the sheet size or the image position on the sheet.
It saves having to cut all sides on sometimes dozens of prints and allows to squeeze more content on a single page, which makes things easier again. For smaller plans I often just use my HP color printer and then cut around the margins (cannot do borderless).
That being said, when I print out photos of/for our family I also like to print borderless. And the combination of the software detecting the virtually larger page size from the printer and being able to set exact print margins (down to 0.x mm) helps to keep the spill-over small. Especially since I do not want the printer driver to enlarge the image, since that would be using (fast/sub-par) resampling again.
Much of your issues with other printer interfaces are due to your choice for a kind of borderless printing on A4 that only the PS printer interface copes with.
I would not say so, because the problems are the same when I print with borders on the HP. Borderless is just another complication on top of the others.
So the file that huge will in the end never be printed in total on for example a 65" wide format?
Exactly, but I do need to have manual control over how the images are cropped and aligned. The latter is important, because on the table the prints are put together to form a large image/map again.
Did you try to get help in the QU forum or propose a new feature for QU ? The QU forum and Mike Chaney form that community you seek I think.
I think that I asked about a 64-bit version a few years back, but I only found an outgoing e-mail reporting a bug (with no answer coming back).
My yearly Adobe subscription just got renewed on 2th, so next year I can look around again.
