Large Format Landscapes

[asuilin]

Would you please tell us how you made a meniscus 167/6.7 lens?

Where did you get the glass blank? What grinding grit did you use? How did you polish the glass? Etc.

Of course, I did not grinded the glass. It's too much even for crazy Russian
Optic for this lens (multicoated plastic) was ordered in ophthalmologist shop. It is just the blank for eyeglasses manufacturing.
There are three important parameters for meniscus:

• diopters - affects focal length
• lens curvature - affects balance between corner sharpness and astigmatism aberration (astigmatism, in turn, affects bokeh smoothness).
• distance between the meniscus and diaphragm - affects amount of coma aberration. The more coma, then more "swirly" the picture. I dont' like swirl, so trying to minimise coma in my designs

The rough design was calculated in WinLens and tuned by trial and error. If you want, I can write detailed post in "DIY" forum.

This is a photos of 167mm meniscus:

It looks and works like a modern lens. No PVC tubes, no waterhouse stops, no old junk. Diaphragm controlled by shutter, as usual.
Yellow-green filter is a part of lens design, it reduces chromatical aberrations (more sharp picture).

[Ramiro Elena]

If you want, I can write detailed post in "DIY" forum.

That would be interesting
I imagine the lens is the two close up lenses between the shutter and the skylight filter? So it is a two element lens?

[neprosti]

simple, you need to directly in the sun and a small aperture
(in color it looks better)

[asuilin]

I imagine the lens is the two close up lenses between the shutter and the skylight filter? So it is a two element lens?

No, it's classical one element meniscus, lens behind aperture. There is no optical element in front, only YG filter to reduce chromatism and protect shutter.

[AtlantaTerry]

If you want, I can write detailed post in "DIY" forum.

Yes, please do.

[Corran]

The rough design was calculated in WinLens and tuned by trial and error. If you want, I can write detailed post in "DIY" forum.

Really great result! That "look" is much prettier and more refined than almost any other meniscus lens that I have seen. If you had a bunch of those made up ready to go with threads for a Copal shutter, I would be first in line to buy one.

[asuilin]

Thank you for kind words, Corran!
The hardest part of lens assembly is a threaded adapter to screw step-up rings into Copal shutter. Adapter should be custom machined and I had difficult times trying to find reliable machinist in Moscow. It was much easier to produce these damn adapters in China than here.
If I have a chance to make more adapters, I'll let you know.

[premortho]

Thank you for kind words, Corran!
The hardest part of lens assembly is a threaded adapter to screw step-up rings into Copal shutter. Adapter should be custom machined and I had difficult times trying to find reliable machinist in Moscow. It was much easier to produce these damn adapters in China than here.
If I have a chance to make more adapters, I'll let you know.

I can't believe that all of the machine shops in the Moscow area are gone. When you hang around with older machinists, and tell your sad story, they'll tell you where to look. Machinists are like photogrphers, they know what everybody else is doing.

[lbenac]

Foggy day this Sunday, so a couple of hours of fun with my dog. The first hour with almost nobody around in the fog - pure enjoyment.

XPO45 Fujinon-NW 125/5.6HP5+ Pyrocat Jobo







When she has had enough of waiting for me taking picture, she gives me a clue by seating or lying down right in front of the camera - clever girl...



Cheers,

Luc

[StoneNYC]

Foggy day this Sunday, so a couple of hours of fun with my dog. The first hour with almost nobody around in the fog - pure enjoyment.

XPO45 Fujinon-NW 125/5.6HP5+ Pyrocat Jobo







When she has had enough of waiting for me taking picture, she gives me a clue by seating or lying down right in front of the camera - clever girl...



Cheers,

Luc

First and third are my favorites, on the 3rd, I wish the stair railing weren't there, but you couldn't help that, it's a great shot