Coating on 3.5cm Elmar

[robbiebedell]

<p>I just bought a 3.5cm Elmar for a very good price. (#271245). I beleive the number is 'pre-war' and it is not supposed to be coated, but it looks as if it might well be coated. It has a faint blue reflection. How can I tell if it is indeed, coated?....Also...does anyone have any filter suggestions? I know it takes A 36 filters, but where can I find those tiny screw in filters? The must be about 18cm...Thanks in advance!</p>

[starvy]

<p>Hi Robbie,<br>

Some lenses were sent back to factory for customers if I am not mistaken. These have coatings. I have a pre war Elmar myself and the glass is clean white on the outside indicating no coating.</p>

[paul_wheatland]

<p>some vintage (prior to WWII) lenses that left the factory uncoated but because of age and oxidation during these years have developed "bloom" which acts somewhat like a coating. IMHO I would not attempt to remove the "bloom".</p>

[h._p.]

<p>You can find out a lot more about lens coatings in http://en.wikipedia.org/wiki/Optical_coating</p>

<p>It's a pretty good article.</p>

[robbiebedell]

<p>Thank you all. I think my lens might have the 'bloom' Paul mentioned. So that is good. The glass is extremely clear for a lens of this age, clearer than my rigid summicron. I have an adaptor ordered and I can't wait until it gets here...</p>

[david_barts2]

<p>Regarding lenses with a "bloom", I seem to remember reading that the idea for deliberately putting coatings on lenses happened when it was observed that old lenses with such a "bloom" tended to perform better than new lenses without one.</p>

[colin_elliott]

<p>A "bloomed" lens is/was a lens that has had a coating applied. e.g. post war Leitz lenses..<br>

Bloomed and Coated are interchangeable terms although one tends these days, to refer to such lenses as coated (or multi-coated).</p>

[winfried_buechsenschuetz1]

<p>I have severe doubts whether "bloomed" and "coated" are synonyms.<br>

Actually a pre-war Novar on my Zeiss-Ikon 6x4.5 Ikonta shows a faint blueish reflection, too. And this lens was not coated originally nor was it sent back for coating...<br>

Some types of optical glass develop some superficial corrosion over time. And sometimes this layer of corrosion has optical properties similar to that of coating. In some cases, intentional "forced" surface corrosion was used instead of coating.</p>

 

[colin_elliott]

<p>Robbie, To answer your second question.. A36 filters are in fact push-on mounts of 36mm diameter.<br>

In Leitz parlance "A" = push-on and "E" = screw mount.<br>

You could try Hama or B+W for these filters or buy a A36 to E39 adapter in order to use the more readily available E39 filters. Leitz did in fact make such an adapter and maybe you could find this or the A36 filters on ebay or other similar souces. </p>

 

[fld]

<p>FWIW, the Elmar lenses will take the same screw-in filters that fit an Argus C3. ain't that a hoot</p>

 

[robbiebedell]

<p>I managed to get one yellow and one uv 19mm filter from Manfred Schmidt in Chicago. Sometimes he has stuff no one else has. He is very knowledgable and very helpful. Just google his name if you are looking for something. Those little filters are hard to find!</p>

[photo5]

<p>According to my Leica Pocket Book 3rd Edition, the 5cm 3.5 Elmar was coated from serial number 581501.</p>