TTH lens flange

[Struan Gray]

I have just treated myself to a lovely, late, coated, 320 mm Aviar. It's a gorgeous thing - TTH machining was just so slick - but it lacks a flange. I have a universal iris that will hold it but I am reluctant to risk mucking up the threads and the finish by doing so too often.

Does anyone know of a good source for imperial-measure standard rings? The Lens Vademecum says this lens needs a 3" flange. Ideal would be an original TTH flange (they were proud of their thread-starting profile), but any blacked brass ring would do.

My standard source for thread gauges is on holiday, so in case I need to get a flange made: what is the thread pitch on these flanges?

[goamules]

From what I've found the TTH flanges are all standard sizes (and usually marked TTH). If you measure the threads at 3", any TTH marked flange that size will fit. Getting lucky with any other make is hit or miss. Usually miss.

[cdholden]

I have a 14" Aviar with black flange. I can check it when I get home tomorrow, but I don't remember seeing the TTH logo on it, unlike the brass Anastigmat I have. Then again, it may not be original. Apparently the previous user couldn't figure out how to install it and just included it in the box. I had to remove the rear element to put the flange on. It was wider than the mounting threads.

[Struan Gray]

Thanks Garrett, cholden.

I am keeping an eye out for a 'real' TTH flange. With metric flanges you can be pretty certain that if you measure the diameter right the pitch and form of the threads will just fall into place. There is so much talk of thread standardisation in the VM and other histories of TTH as a company that I was hoping it was a standard adopted by other Anglo-Saxon makers too.

I have other lenses in flanges which cost more than the lens itself, and this is the sort of situation where it's worth paying for the knowledge base of someone like S.K.Grimes. But if I can find a matching flange of the same vintage, it just feels right to do so.

I suspect there's money to be made buying up Entals and selling the flanges seperately :-)

[carverlux]

Struan,

There are 2 Aviar versions from Cooke - do you have a f/4.5 Series II or a f/6 Series IIIb? (Well, the IIIb is technically an Aviarica but they are marked Aviar on the lens).

They take different flanges: the Series II 320mm takes a coarse thread, RPS 3½" screw flange but the Series IIIb 320mm does not have a RPS screw - it has a much finer pitch than the normal TTH RPS screw and is slightly smaller in diameter. I have both lenses and the difference is very clear.

Sounds like a custom flange or the old standby iris may still be your best bet.

carver

Thanks Garrett, cholden.

I am keeping an eye out for a 'real' TTH flange. With metric flanges you can be pretty certain that if you measure the diameter right the pitch and form of the threads will just fall into place. There is so much talk of thread standardisation in the VM and other histories of TTH as a company that I was hoping it was a standard adopted by other Anglo-Saxon makers too.

I have other lenses in flanges which cost more than the lens itself, and this is the sort of situation where it's worth paying for the knowledge base of someone like S.K.Grimes. But if I can find a matching flange of the same vintage, it just feels right to do so.

I suspect there's money to be made buying up Entals and selling the flanges seperately :-)

[Struan Gray]

Carver, thanks. How do you like your lens?

Mine is a IIIb Aviarica f6. I had noticed the fine threading - the whole lens exudes an air of instrumentation that is a cut above the usual lens metalwork.

It sounds as if searching for an existing flange is an exercise in frustration. I have workshops which can make anything if you really want it, but as always, it's a question of price.

I'm going to play with the lens for real over the Easter weekend. If I like the results as much as I think I should (I have a dialyte thing going :-) I'll probably spring for a real flange.


Struan

[carverlux]

Struan,

My experience with my copy of the IIIb is simply stunning, the II not so good. Cooke came out with successively slower versions of their main lines and in general they are better performers than their namesakes.

In my little TTH stash, my particular favorites in coated ones are IIIb, VIIb, IX and XIV, and of course the IIE. For uncoated, the original Series II Portrait non-knuckler is in a class by itself - I like it much more than even the v1 Heliar.

I have a soft spot for TTH also because of their metalwork. Being instrument makers at heart, their precision is on a level than others simply cannot contemplate, much less compete with. The Taylor lens screw is simplicity itself to align and thread on. It only takes seconds to put on even a huge lens. In contrast, just last week, I must have spent close to a half an hour threading a Voigtländer onto its own flange. The solid, robust RPS screw is very superior, even today.

So if you decide to have a flange made for your IIIb, I'll piggy back on yours and get one from your machinist too (especially if he can make it in brass). I use my iris flange to hold it now and it seems OK but nothing beats a beefy brass flange!

carver

Carver, thanks. How do you like your lens?

Mine is a IIIb Aviarica f6. I had noticed the fine threading - the whole lens exudes an air of instrumentation that is a cut above the usual lens metalwork.

It sounds as if searching for an existing flange is an exercise in frustration. I have workshops which can make anything if you really want it, but as always, it's a question of price.

I'm going to play with the lens for real over the Easter weekend. If I like the results as much as I think I should (I have a dialyte thing going :-) I'll probably spring for a real flange.


Struan

[Struan Gray]

Carver, thanks for sharing your experiences.

I'll let you know if/when I get a quote for a flange from the workshops here. As a rule, S.K. Grimes is cheaper for 'normal' things like this - our people are the ones to go to if you want a flange in mirror-polished molybdenum with 100 M1.2 tapped holes around the circumference.

The Aviar is my first TTH lens, but I'm a long time fan of 4-4 designs. I use APO-ronars in 240 mm and 420 mm as longer lenses on 4x5, and I have an uncoated 12" Ross Homocentric which produces a very distinctive flattened look as a long portrait lens on 6x6 roll film. I'm hoping the Aviar will be a less flarey version of the Homocentric, while not being quite as clinical as the APO-ronars.


Struan

[carverlux]

Struan,

Both the Series II and IIIb variants are quite flare-prone, even when coated. Uncoated, they are as picky to use as a Goerz Celor. For all the hype about their sharpness and resolution, they are not that sharp wide open, which defeats the intention of the f/4.5 and f/6 apertures they come with.

If you are looking for a slightly more "poetic" Apo-Ronar, look for a TTH Series XIV. These elusive triplets do not show up often and are not very well documented but immensely delicious in use. TTH positioned them as "between a process and a portrait" and I can confirm that is right on. Used at f/6.3, it is just ever so slightly less dreamy than a wide-open Golden Dagor and favorably compares in resolution with either an Apo-Ronar or a Red Dot Artar. Only an uncoated Series II Portrait can bring more romance. Too bad they are not easy to find.

Discovering all the finery TTH brought us over the years is a very rewarding experience and I wish you lots of memorable finds and revelations.

carver

Carver, thanks for sharing your experiences.

I'll let you know if/when I get a quote for a flange from the workshops here. As a rule, S.K. Grimes is cheaper for 'normal' things like this - our people are the ones to go to if you want a flange in mirror-polished molybdenum with 100 M1.2 tapped holes around the circumference.

The Aviar is my first TTH lens, but I'm a long time fan of 4-4 designs. I use APO-ronars in 240 mm and 420 mm as longer lenses on 4x5, and I have an uncoated 12" Ross Homocentric which produces a very distinctive flattened look as a long portrait lens on 6x6 roll film. I'm hoping the Aviar will be a less flarey version of the Homocentric, while not being quite as clinical as the APO-ronars.


Struan

[goamules]

...If you are looking for a slightly more "poetic" Apo-Ronar, look for a TTH Series XIV. These elusive triplets do not show up often and are not very well documented but immensely delicious in use. TTH positioned them as "between a process and a portrait" and I can confirm that is right on. Used at f/6.3, it is just ever so slightly less dreamy than a wide-open Golden Dagor and favorably compares in resolution with either an Apo-Ronar or a Red Dot Artar. Only an uncoated Series II Portrait can bring more romance. Too bad they are not easy to find...

carver

I agree. Too bad I sold my 21" Series XIV here on this board. Why? It needed a flange!
I took this 8x10 portrait with it before I sold it. "My kingdom for a flange..."