View Full Version : What is this?

Erik van Straten
09-12-2018, 05:55

I've found this very nice soft rubber lens cap. The diameter is 40mm. The cap fits none of my lenses. Who knows anything about lens caps like this?

The logo looks prewar to me. The cap is heavily used, but for what?


Vince Lupo
09-12-2018, 06:32
Maybe the Xenon?

09-12-2018, 06:37
Does it fit on the hood of one of your lenses? Maybe the back side when the hood is inverted for storage?

Erik van Straten
09-12-2018, 06:52
Maybe the Xenon?

Thank you, Vince, for this suggestion. My lens book by Rogliatti says that the Xenon accepts the (slip on) shade of the Hektor 73mm. I have that lens and that shade, but this lens cap does not fit this lens, so it will not fit the Xenon either.


Erik van Straten
09-12-2018, 06:54
Does it fit on the hood of one of your lenses? Maybe the back side when the hood is inverted for storage?

Thank you, capitalK, but I've tried them all.


Erik van Straten
09-12-2018, 07:08
capitalK, you were on the right trace!

Maybe I've found it. I have the prewar Cooke and Perkins shade for the Elmar 50mm f/3.5 that offers control of the f/stop of the lens. This lens cap slips neat into this shade, right from the front. Exact fit.

When I look at the lens cap very closely, I see traces of wear on the outside, not on the inside. That gives me the certainty that the lens cap belongs to the Cooke and Perkins lens hood. Unbelievable. The Cooke and Perkins lens hood is in itself very rare!

I will make a picture of both together.

Finally back together again! After so many years.





09-12-2018, 07:35
That is one cool lens hood! Very functional!

09-12-2018, 19:18
I've thought about trying to find one of those hoods. Now I learn there is a possibly even rarer cap for it. I think I'll give up while I'm ahead, but am very happy yours got together.