Film Update: Even Kodak Doesn’t Know What’s Going On

I spent about 45 minutes in Target the other day trying to find the answer to a simple question; what is the pixel resolution of the images you receive on a Kodak or Target Picture CD.

No one at Target was able to tell me. So, being at least customer oriented if not knowledgeable, they called Kodak tech support and handed the phone over to me. After a substantial amount of time on hold, the tech was still not able to give me an answer, and eventually hung up on me.

On the other hand, a very knowledgeable representative over at CVS informed me that the resolution is variable based on the quality of the negative, and was able to determine that the resolution of the current job running was 1918 x 1300 or 2.5MP.

My most recent film processing and scanning was done at Millburn Camera/ASAP Photo in Millburn, NJ. Their scans were 3088 x 2048 or 6.3MP. This is about the same resolution as the 6MP Nikon D50, which is 3008 x 2000. This is a standard scan which comes with the development of a roll of film.

What’s interesting is that there does’t seem to be an agreed upon standard as to how resolution is specified. One provider describes the resolution as 8 x 10 @ 600 dpi (by the way, there are no “dots” in an image file), another gives the resolution in pixel dimensions, while yet another describes the images in terms of pixel count (for example, 12MP or “megapixels”.)

600 dpi doesn’t tell you much of anything. The image could be 600 “dpi” at 14.3" x 9.5" or 600 dpi at 3" x 2"; the two would be very different resolutions. Megapixel specifications are a little more informative, but only if you know the aspect ratio; a 12MP image could be 4288 x 2848, or it could be 3494 x 3494; the two would be very different formats, one being square, but technically have the same image area.

The most important image specification is simply the pixel dimensions. One 4000 x 3000 pixel image is the same as another regardless of ppi resolution or inch dimensions, or whatever.

Back in the day, scans would be specified in lines. A 6000 line scan would be 6000 pixels across the width of a 35mm slide, creating an image 6000 x 3985 pixels that is 20 inches by 13.3 inches at 300 ppi. That made a lot of sense. Today, scanning may be specified as 4000 ppi, which would be at the native dimensions of the media in question. For example, a 35mm slide which measures 36mm x 24mm would result in an image of 5669 x 3780 pixels that is 18.9 x 12.6 inches at 300 ppi.

See how confusing this all is? After working in web design for a number of years, I’ve become accustomed to working in pixels, which has made life a lot easier for me.