Does anyone have information on "studio" shutters? I often see them sold with older Wollensak portrait lenses, particularly soft-focus models. Was the shutter made by Wollensak? Is it mounted in the lens barrel or behind like a Packard? Does the shutter function on T, B, or both? Is it air-driven with a bulb apparatus or with a standard cable release? Finally, are there any typical mechanical defects that I should look for when buying used? Thanks.

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