Half Rodenstock

Is a half Rodenstock 300 mm f:9 of any use? The back element and the apperture blades are missing.

Paperweight.

Steampunk monocle.

<p>On many lenses, the front element alone will work as a very long lens. This is the idea behind the older multiple focal length convertible lenses, The front element gives one focal length, the back another and the two elements together a third. The quality drops off with using only one element, but it can be fun to play around with just the front or back element of a lens.</p>

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<p>You could horse around with it, but I wouldn't waste too much time. If it's f/9, it's from a process lens, with no iris diaphragm, so it's not useful photographically. (Is there such a word?) If it focuses, the single cell would be 600mm, give or take. Nice paperweight like Bob says.</p>

<p>I would try putting it on eba as it is. You never know but your opposite number may be out there wondering what to do with the back half.</p>