New 75mm Hypergon Lens

[Havoc]

Please explain further. I ask because Rodenstock's Pantogonal, a 3 element lens and neither retrofocus nor Russar type, was offered with a flat center filter.

"This consists of a plano-convex lens of yellowish green glass which absorbs very strongly blue and violet light, and a plano-concave lens of a colorless, very transparent material. The optical constants of both these lenses is exactly equal so that the cemented lenses act as a plane parallel plate which is dark in the center and transparent at the sides."

"Yellowish green glass"? Not uranium glass I hope.

[Mark J]

Oh yes, it might be - from that period ....

[John Layton]

Jeesh...that little fan just keeps looking better and better!

[rayfor]

Hey guys, I've decided to make that little fan as central filter. I will upload latest info in the main thread.

[ridax]

Good news.

[Greg]

Hey guys, I've decided to make that little fan as central filter. I will upload latest info in the main thread.

Viable option of using a laser cutter to cut the thin metal fan and bending the thin metal fan and three wires on separate jigs? A local hobbiest jeweler makes earrings (actually quite similar to the Hypergon fan) and prefers laser cutting metal and bending it to using a 3D printer. Just thinking out loud...

[Hugo Zhang]

So one needs to have two air bulbs with hose to make an exposure with this lens? One to blow the little fan on the front and the other one for the Packard shutter?

[rayfor]

I use a sinar DB shutter rather than a packard shutter so only one air bulb is needed.

[rayfor]

Viable option of using a laser cutter to cut the thin metal fan and bending the thin metal fan and three wires on separate jigs? A local hobbiest jeweler makes earrings (actually quite similar to the Hypergon fan) and prefers laser cutting metal and bending it to using a 3D printer. Just thinking out loud...

Exactly, I use a 3D printed punching die to bend it.

[rayfor]

So one needs to have two air bulbs with hose to make an exposure with this lens? One to blow the little fan on the front and the other one for the Packard shutter?

I use a sinar DB shutter rather than a packard shutter so only one air bulb is needed. Sinar DB offers accurate and fast(considering its size) shutter speed, which is important if you want to use it with normal speed film in daylight.