Actually the title may be a little misleading in that this article is not about printing directly from prints – whatever that would mean. Let me explain. Recently I have been engaged in a project of scanning and digitizing my old film prints. You know the kind. Shoot a roll of 35mm film and then take the roll to your favorite One Hour Processing centre or even to one of the other consumer processors such as the big name chain pharmacy outlets who offer film processing. What you get back are the standard, unless you specify otherwise, 4” x 6” prints.
My project now is to scan and digitize those prints – or at least the meaningful ones – for the purpose of long term protected storage and also to more easily share on line. Though some will be selected for later printing in a larger format, most will not be. Of those which I may later select for printing, a decision will have to be made about how large the final prints can be. You can only make a digital image into so large a print before it starts losing image quality.
My dSLR (Canon 40D) is about 10.5 megapixels. Surprise! You figured I might use something more the order of a 120 megapixel camera. Is there such a thing? Ok, digression aside, for my camera the specs come out something like this.
For a image converted from RAW to TIFF at a resolution of 300 pixels/inch an image of the following pixel and image sizes results.
I generally don’t try to produce a print from a digital image greater than two times those print dimensions. I know that in some cases, depending on the image itself and its sharpness as well as the results of any artistic post process editing I may have done, it might be fine to go a little larger but I think that a print of 16” x 24” is about the most I want to go for.
The specs on a scanned and digitized 4” x 6” photo print are these. Scanned at 300 pixels/inch.
Of course the actual measurements will depend on the preciseness of the image crop on the scanner bed and any subsequent cropping in the photo editing software to remove any white edges. The numbers will be real close anyhow.
So based on my practice of limiting the physical print size to no more than twice the original print size, producing a print of 8” x 12” is as large as I will consider. Though going larger in some cases might be ok, considering that the original print as it is produced by the consumer photo print services is not going to be of the greatest quality, going much larger is likely to show the imperfections of the printing process.
Now how about printing from an image digitized from the original film negative? Another subject for another time.