When one is planning on a print size 14x28; do you size your canvas for that print size and then paint, or do you paint at a smaller size and then print at the larger size?

I prefer to create at the size I'm going to print. This eliminates ugly surprises and/or rework when an image is upsized.

Others who use plugins like Genuine Fractals, Blowup, etc. may have a different take.

Some commercial printers can take your original and enlarge it considerably (with decent results) using RIP software.

For those using Painter (only) here's an approach I've read about, but not actually used...
* Open a new file, say, 7.5x14
* Show Painter's "Scripts" palette; start a new script (from the Scripts menu)
* Paint until you're done without interruption... don't worry about mistakes, do overs, etc. Just keep going.
* When finished stop recording the script
* Save/close 7.5x14
* Open new 14x28
* Apply the script just recorded to the new file. Painter will take the new size into consideration and faithfully scale and apply the strokes one after another -- mistakes and corrections -- until finished. This method was popular when Painter was really, really slow. Don't know if it is used much anymore.

thanks Danny