Gigapxl Project


General Photography

We live in a culture where bigger is supposedly better. Thus, the Gigapxl Project just had to happen. Quite ironically, the project is film-based (with 9” x 18” exposures), with the final Gigapixel images resulting from scanning. If you do this kind of exercise you can then, for example, show where I live. And you can also learn a bit about some very technical information, which explains how you arrive at the number of pixels.

Indirectly, it also teaches you about the number of pixels for standard film formats. The other day, I scribbled down a similar calculation, and it seems my calculation appears to be correct. If you assume 100 pixels per mm (which is their number) you arrive at 8.64 Megapixels (MP), 36 MP, 129 MP, and 516 MP for 35mm, 120, 4x5, and 8x10, respectively (if I haven’t just mistyped the number in my pocket calculator). Thus, it’s easy to see why even fairly cheap digital cameras can achieve 35mm quality easily, whereas 120 is still a bit of a stretch. The resolution achieved with large-format photography is still another league.

To make it really geeky, you’d have to factor in that many good films can resolve more than 100 pixels (or lines) per millimeter, which gives you another factor with which you have to multiply the sizes given above. Using some numbers I found online gives these as 1.0, 1.0, 1.44, 1.56, 2.56, 10.24, and a whooping 81.0 for Kodak’s Tri-X 400, Kodachrome 64, Agfa Scala (200), Kodak’s E100SW (E100G might have an even higher number - I couldn’t find it), Fuji Velvia (50; 100 might be more), Kodak’s (sadly discontinued) Technical Pan, and Gigabitfilm (25), respectively. Needless to say, you also have to have an excellent lens for this.

Thus my 120 Agfa Scala slides, shot with a Rolleiflex, are in the neighbourhood of maybe up to 50 MP; and when I shoot 35mm TechPan, using one of my Leicas, I am easily in medium-format territory. If somebody wants to argue that the cameras won’t be able to get that high, that’s fine; I’m happy to reduce these numbers by a factor of two - that’d still be quite impressive.

I really don’t want to make this another post about digital and film - with too many people suspecting (wrongly) that I’m anti-digital already. I think it’s just instructive to see what the numbers are. Needless to say, in the end, it’s all just silly math - but that’s what I do for a living!

PS: For those confused about units (will the US ever adopt sensible units?) there are 25.4 mm in 1.0 inch.