I find something intriquing about medium format folding cameras. I think it is due to the combination of larger MF negatives, pocketability, simplicity, and realitvely low cost.
While collectors rush towards the later models with best lens and shutter combinations, there are many quality folders that go for only $20. I'm now up to three, a 6 x 4.5, a 6x6, and a 6 x 9.
If someone doesn't own a medium format camera, they are cheap way to get into it. Compared to a Lomo camera, even the simplest folders have a triplet lens (versus single element plastic lenses), 3 more shutter speeds, and an adjustable aperature that is 2-3 stops faster at its widest.
If I had to recommend one for someone looking for a folder without wanting to commit much money, it would be one of the post-war Zeiss Nettar. Zeiss has the best reputation for build quality and their bellows are typically still light tight (as opposed to the Agfa and Ansco models). Post-war lenses are coated which help reduce flare and increase contrast (nice but not absolutely necessary). They typically go for $20-$30. Zeiss had a million different models, so a picture is worth 1,000 words:
That all being said, here are mine:
Zeiss Ikonta 520 A. It's 645, uncoated Tessar and Compur Shutter
Agfa Ansco Speedex B2. It's a 6x6 with a uncoated Triplet lens on an unnamed Compur-like shutter.
Zeiss Ikonta 523/2. A 6x9 with a Prontor-S shutter and a coated Novar (triplet) lens.
