Giclee and the question of resolution
I want to go over one more time about the question of resolution. We recently got a few files from customers who want us to print giclees. These files have are between 60 and 70 ppi (pixels per inch). PPI is the number of pixels per inch and it is not to be confused with DPI, which is dots per inch. We can print a perfectly fine giclee at 150 ppi as our printers can go up to 2880 DPI. One dot does not equal to one pixel!
On the other hand, a 70 PPI file does not have the necessary resolution to print on smooth papers but will be easier with canvas because of the inherent texture (which masks some of the lack of resolution). Interpolating with software does help somewhat but it is not a magic bullet. This is why professional photographers do buy high end digital cameras that cost $20,000 and more. If they could get away with a $1,000 system, they would. Nobody wants to waste money. Same with scanners. You can pick up a cheap scanner or spend $40,000 on one. It has to do with range, resolution and other factors.
Interpolation is a tricky business. Software is not intelligent and it cannot (at this time) make up information that it does not know how to fill. To make a file larger, interpolation averages values on a scale to inflate size. It puts in "fat", not "muscle". There are different flavors of interpolation. Adobe uses bicubic, bilinear and nearest neighbor. They have different applications. Other software manufacturers claim they have more sophisticated methods but truth is, these are small companies who do not have Adobe's resources. If Adobe can't come up with something better, rest assured nobody else has.
Finally, two files with the same low PPI can make a very different quality of print. A large gicle print made from a high end professional digital 6MP SLR will beat hands down one made from a consumer level camera with the same MP.
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