ICA Niklas

[ljherrero]

Hi,

I have recently acquired an Ica Niklas lens ( https://www.ebay.es/itm/194495742589...QAAOSw94phiSSs is not this, but identical, although mine has a higher series number), which by the little I have been able to inform me was a lens for a projector of the same firm (ICA) and surely manufactured in the twenties of the last century. The fact is that I have not been able to find almost any information about its characteristics and optical formula except for a reference not very specific at its focal length that would be 6 "1/2 (that is 165mm. Approx.). If that were the focal, the apparent luminosity would be f/3.5 or f/4; as it admits lateral insertion of Waterhouse diaphragms, I have manufactured two of f/5.6 and f/8 (more or less). As something dirty was, I had to dismantle it Its cleaning and I can say that it is composed of a cementad doublet (I think) front and three rear elements and after the diaphragm slot; that is, five elements in four groups (the third and fourth elements next, but not cemented).

Can someone give me some information about this lens?

Thanks

[ridax]

Your description most probably suggests a modified Petzval type.

But with the lens in your hands, why not to try it - at least looking at the image on the ground glass only - instead of asking questions to the people that do not have the lens?

[Ron (Netherlands)]

Nice find. Here's one on the ICA projector for which it was apparently made (a forerunner was the projector made by Hüttig which sported the same lens - see last pic below, it was apparently the lowest class/cheapest lens which could be chosen for this projector):





and another configuration ....

[ljherrero]

Thanks for the info; Apparently this objective had a long life in ICA: here ( https://www.ebay.es/itm/123729228613...kAAOSwsNBbinGD ) one that should be something more recent, but with coal arc light ...

Here ( https://www.optical-toys.com/files/D...%20Excerpt.pdf ) information similar to what your appointments, from an ICA catalog of 1911.

[ninadobrev]

Hi,

I have recently acquired an Ica Niklas lens ( https://www.ebay.es/itm/194495742589...QAAOSw94phiSSs is not this, but identical, although mine has a higher series number), which by the little I have been able to inform me was a lens for a projector of the same firm (ICA) and surely manufactured in the twenties of the last century. The fact is that I have not been able to find almost any information about its characteristics and optical formula except for a reference not very specific at its focal length that would be 6 "1/2 (that is 165mm. Approx.). If that were the focal, the apparent luminosity would be f/3.5 or f/4; as it admits lateral insertion of Waterhouse diaphragms, I have manufactured two of f/5.6 and f/8 (more or less). As something dirty was, I had to dismantle it Its cleaning and I can say that it is composed of a cementad doublet (I think) front and three rear elements and after the diaphragm slot; that is, five elements in four groups (the third and fourth elements next, but not cemented).

Can someone give me some information about this lens? contexto

Thanks

The Ica Niklas lens you recently purchased appears to be a vintage ICA lens produced in the 1920s. Your research indicates that the lens is made up of a front cemented doublet, three rear elements, and a diaphragm slot, totaling five elements in four groups. The estimated focal length is 165mm (6 1/2 inches), which corresponds to an aperture of about f/3.5 or f/4.

[ljherrero]

Thanks for the reply. I disassembled the lens components to try to clean them (accumulated dust) and I was able to verify that, indeed, there are five elements in four groups ( http://forum.mflenses.com/ica-niklas-t83588.html )