Issue tiling a raster/vector image in Photoshop, Illustrator, Inkscape

[Justin]

I've been working with some graphics since last night. I have a square image and I'm tiling it into 2x3 to make a larger recurring pattern. Done this before and always worked fine. Last night I was doing this with a jpeg in Photoshop and I got the 6 blocks aligned, copied and pasted into a different document and there was a distinct loss of resolution.

I spent an hour and a half on live chat to Adobe and in the end the agent told me I should work with vectors in Illustrator and Photoshop wasn't intended to do this! We discussed raster images etc. and he tried everything dialled in but just said it's my image. So, I have a 55 inch square image that I shrink to around 1 inch square, no quality loss, I tile 2x3 and flatten layers, no quality loss. I copy and paste into a new document, noticeable quality loss!

I explained that I usually get jpegs to work with and rarely get vectors due to the nature of my business so that's no help at all!

So today I'm in the office, just happens this particular graphic I have an EPS file. I've tried tiling in Illustrator, I don't get on with it but had a go...still don't get on with it Downloaded Inkscape, found this easier and tile feature worked very well. Left a pixel sized gap between the tiles, a known raster engine fault. Overlapping a micro amount seems to help but daft to have to do this.

I prefer CorelDraw, copy paste job done. Step and repeat is good but I can't get 2x3 as I need just yet. I'm finding when I zoom in to align the edges the PC is stalling. it'a s decent powerful PC with good graphics card and never had this issue so I think it's software related, the original image may be too large.

So, how would you duplicate a pattern image into a 2x3 tile to create one rectangular image without gaps?

[webtrekker]

If you import a very large EPS into Photoshop and set the size much smaller then you are bound to end up with a seriously pixellated image.

The bloke from Adobe was right - reduce the size in a vector program first (such as AI, Inkscape, etc) then save the result as a bitmap for tiling in Photoshop or whatever, or just tile it in the vector software.

[Justin]

Still playing with this, appreciate what you're saying.

I'm in CorelDraw with the EPS reduced to 50mm square, quality is fine. I can use step/repeat etc. but I still get the pixel wide white line, even a micro nudge won't work and an overlap shows the line. I un-grouped the image thinking there may be a border but there isn't.

Is it 'possible' that the line will appear on screen but won't show on a print?

[Justin]

Looks like the line will still show.

I have the file at a good high res in CDraw but when I export it loses quality, what would be best export format?

I have a few of these tiles to do, recurring patterns, not sure what I'm doing differently but done plenty before (let's blame the graphic!) Is CDraw the best choice?

[pisquee]

We do tiling our repeat blocks in Photoshop, which includes resizing, as our designs are made up to 52cm with for wallpapers, but then need rescaling for fabrics printing etc.
PS does fine at this job, but you do need to zoom in to 100% to ensure the pattern match is pixel perfect (above 100 can make it easier too)

One issue we have come across if when cropping a design to the repeat block, sometimes PS puts the opacity of the outside edge pixels at 50%, so when tiled up, you get a whitish gap around each block - to get around this problem, we duplicate the layer, and then the two 50% opacity pixels add back together to 100% - we make sure this is done when necessary when finalising repeat block designs.

If you're getting a quality difference when loading a design into another file, then I would think that this is a different issue from anything to do with it being a repeat. I've noticed you can get different results as to how you load designs into new/existing designs in PS - if you drag a file from Bridge into an open PS document it comes in as a Smart Object, but not always at the correct size/scale (not worked this one out yet) IF you load the file separately into Photoshop, and then duplicate the layer from one to the other then this problem doesn't occur (unless there is a difference in dpi between the two.)