Heidecke's Monster

Started Sep 30, 2022 | Discussions thread
OP Bosun Higgs Regular Member • Posts: 425
Re: Heidecke's Monster

Eggplantt wrote:

A very impressive effort! I didn't know they were Petzvals- where does the rear glass stop in that assembly?

Yes, it's defintely a Petzval. I was really chuffed when I confirmed this as nearly all of my favourite bokeh lenses are Petzvals. Unfortunately The Monster just doesn't deliver the bokeh effects or field curvature that most Petzvals have in spades.

I suspect the MF+ coverage is to blame, my tiny FF sensor is just not reaching the interesting bits of the image circle. Yet another lens that would benefit from a larger coverage "Speedbooster" focal reducer, if one existed!

The rear of The Monster after a visit by Mr.Hacksaw. There was originally about 40mm more lens tube here.

My photo shows The Monster's rear element's current position. It was originally much more recessed but I hacksawed about 40mm off the rear of the tube to provide more room to accommodate the mount and helicoids. You need a lot of helicoid travel as the rear focus on this lens is very slow.

I have not blackened the cut edges of the tube as it is completely covered by my mounting solution.

I saw 'Heidecke' and got confused with the Reichmann projection lenses, for some reason. They are Cooke triplets, also large, and like many large format, long focal length lenses, were it seems pressed into service for 35mm / 6x6 film projection:

But I hesitate to infer conclusions about how which lens ended up in what lineup.

I have actually handled one of the longer Reichmann projection lenses. Your photo actually shows only one lens, not two. The smaller unit is the optical block and this slides inside the front (bottom) of the larger unit, the small knob on the side of the larger section screws in to hold the block in place.

The larger unit is simply a hollow tube with no elements, and serves only to hold the block at the correct distance to provide suitable focusing range via the helical groove on the opposite end.

It is similar to the arrangement in Leica Hektor projection lenses. The Hektor triplet block also slides inside a long hollow sleeve, but in this case the block rides in helical grooves inside the tube to allow focus, whilst the tube itself remains static.

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