I just ran an interesting if unscientific comparison between 4x5 (Wista DX, 150mm f5.6 Caltar (recent version), Velvia quickload in a Polaroid 545) and a decent digital SLR (Nikon D70 with the kit lens). The Velvia was scanned with an Epson Perfection 3200 (the sometimes-maligned two year old one, NOT the brand-new filmscanner) at only 1600 dpi. I wanted to stay under the REAL resolution of the scanner, and I know that critter doesn't actually get 3200 dpi-opinions vary between about 1600 and 2400 dpi actually resolved. This wasn't a scientific "same picture" comparison at all-it was just a look at what each could do with real-world shots.

Of course the 4x5 is going to WALK away with this test at huge magnification-4x5 beats much fancier digital cameras than this all the time. I wasn't interested in "actual pixel" magnifications or uprezzed files that equate to a print 4 feet wide-who ever prints that big? The digital shots were specifically chosen NOT to test the limits of the technology-no outrageous dynamic range or high ISO, normal focal length) I wondered what would happen in a real print, at sizes that I actually print. I have access to two nice photo printers, both from Hewlett-Packard. The big printer (at school) is a DesignJet 130, and the little one (my own) is a Photosmart 8450. The first test was a 16x20 (about 14x20 from digital, due to the aspect ratio) on the DesignJet. I had to scale the D70 file up, of course, in order to print it that big-I did this using Photoshop's bicubic interpolation routine. Everything was Unsharp Masked by eye for best appearance at final size. I couldn't find any HP paper that big, so I used Epson Photo Quality Gloss, profiling it as HP Premium Glossy. The 4x5 absolutely ran away with that test. The D70 print looks OK, so long as there isn't a print from 4x5 in the room, while the 4x5 is gorgeous! After seeing this, I must say that I really no longer consider the D70 a 16x20 capable camera...

After looking at these results, I decided to see how small a print still had a difference. Many people claim that 6MP digital is essentially perfect at 8x10, that there's no need to shoot anything else unless you're printing bigger than that. Time to fire up the Photosmart 8450, a brand new 8.5x11 printer with a reputation for very high resolution and wide color gamut (its native color space is Adobe RGB, not the usual sRGB). There's nothing better for small prints (excluding, of course, contact printing 8x10 Velvia on Ilfochrome and similar esoteric wet processes). I expected the two to be essentially indistinguishable at such a small size. I was surprised when the big camera still showed a clear advantage in an 8x10 print. Unlike the 16x20, you DO have to look closely to see this one. If you take a cursory glance, the digital print is just as nice, but any sort of inspection shows a great depth to the 4x5 that the digital lacks. Whether this is due to extraordinary detail, or to dynamic range (and the characteristic curve of the film), I don't know, but the advantage is clear even in a small print.