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  Monday  December 31  2007    06: 38 PM

large format

Large Format Resolution


Resolution isn't everything in large format (LF), and often the most distinctive LF effects involve using classic lenses or techniques that reduce resolution but produce a look that can't be produced any other way.

That said, I posted a demo a while back on my website to give some idea of what an 8x10" neg is capable of —at the link, use the links underneath the picture to click up through successive increases in resolution to get an idea of how much information is really there. Bear in mind that this was scanned on an old Agfa Duoscan that has an optical resolution of 1000 ppi (about 1/5th of what is practical on a drum scanner), and the largest image in the demo is 50% of full resolution. Even so, you can easily see individual bricks in the building next to the school bus. The film is T-Max 100, and the lens is a single-coated Goerz 12" (305mm) ƒ/6.8 Gold Dot Dagor from the 1940s or 50s—a fine lens, but not as sharp as a modern plasmat. So I haven't done anything really to go out of my way to maximize resolution, and still...well, most people who haven't seen an 8x10" negative are impressed by the demonstration.

And just to show you the interesting "low resolution" side of large format, below is a scan of an 8x10" albumen print from an 8x10" neg, made with a classic 360mm Voigtlander Heliar lens at a wide aperture (about ƒ/5.6).


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Looking at the link to what an 8x10 neg can do does give me 8x10 urges but 4x5 and 5x7, which I have, does pretty nice on holding a lot of information on a negative. I have also wanted to explore the "low resolution" side. My 4x5 Graflex SLR has a 210mm Tessar that opens to f3.5. After I get some exposures off on the Burke & James Press I will load some film up on the Graflex. I'm looking forward to see what I get.