3” diameter shutters feature a modified Cokin style filter mount. Can be mounted on any lens that accepts a standard Cokin “P” series screw-on adapter ring. All 120mm to 285mm Wollaston LF lenses use 72mm Cokin rings (supplied with the shutter). Depending on availability, reconditioned shutters may also be supplied at significantly reduced cost.

3-1/2” diameter shutters feature an 

88mm internal diameter collar. Designed for the larger 120mm to 1000mm VLF Wollaston lenses. The collar’s internal rubber traction band grips the lens firmly without marking. See this shutter in action here...

See this shutter on YouYubehttps://www.youtube.com/watch?v=JXc2E94_aMw&feature=youtu.be
See this shutter on YouYubehttps://www.youtube.com/watch?v=2n-4Rp1lB5A&feature=youtu.be

This front mounted shutter system uses the time-proven, reliable Packard-Ideal pneumatic shutter installed on a compact panel mount. Two Packard types are available, the #5 is a basic manually timed unit. The shutter remains open as long as the bulb is squeezed, A quick squeeze and release is about 1/10th second exposure.

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The #6 Packard features two modes: inserting a special pin yields a consistent 1/25th second exposure with a single firm squeeze on the bulb. Removing the pin reverts the shutter to the #5 mode (fully manual timing). The pin is precision ground tool steel, using a common nail may result in erratic and imprecise operation of the shutter. Do not insert the pin while the shutter is open, damage to the blades may result. Do not use a lubricant.

                                See the #6 Packard in operation here....

There is nothing new here, it has all been invented long ago...

Je ne cherche pas. Je trouve.   I do not seek. I find, ...Pablo Picasso

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