49 replies to this topic

[Andrea B.]

This is a new filter to me. Do you have a link for it? What is its purpose? Thanks!!!

[JMC]

Andrea B., on 31 August 2018 - 14:23, said:

This is a new filter to me. Do you have a link for it? What is its purpose? Thanks!!!

It was the one that originally came with the UV Nikkor, Andrea.

[Cadmium]

Yep, the square glass filter seen here, part of the original UV-Nikkor kit.
I could not find any photos of the filter box showing a part name/#, so I don't know what it is technically called. And I don't know if that is what Bjorn meant by "FF filter".

Edited by Cadmium, 31 August 2018 - 19:50.

[JMC]

Steve, the little cardboard box for mine had no part number or name on it other than the "Nikon" logo.

[Cadmium]

Thanks Jonathan. :-)
I am betting that the original square filter that came with the UV-Nikkor is in actuality Hoya U-325c, Which is very similar to U-330, which is the Hoya equivalent to Schott UG5.
I am pretty sure the square filter is made of Hoya U-325c filter glass.
So that means that it has a fairly strong visual transmission, not quite as strong as U-330/UG5, but close, having some blue and even green depending on thickness.
What is the thickness of your square?

Edited by Cadmium, 01 September 2018 - 08:26.

[JMC]

No problem Steve. It's 3.5mm thick.

[Cadmium]

Thanks Jonathan. :-)
Here is a fairly rough and not exactly exact overlay of these three filters, so it looks like I was slightly off on my guess, but still.
Keeping in mind then that the Hoya graphs/data is for 2.5mm thick, and the Nikon filter graph/data is for 3.5mm thick, as Jonathan has noted above.
My overlay may be a little off here and there, but close, best I could do.

Edited by Cadmium, 02 September 2018 - 00:50.

[Andy Perrin]

What does it look like to you when you look through it with your eyes? You would see blue and red from the spectrum, but I'm having some trouble imagining how things would appear. Trees would be black obviously and the sky would be blue...

[Stefano]

Looking through my ZWB2 filter I see a violet sky and bright red trees. The sky is out of focus because we are short-sighted in blue light and below. Some objects (like an incandescent lightbulb) appear with a red filament surrounded by a violet blob.

Of course this filter is more "leaky" than a ZWB2 (even if there are a lot of different ZWB2s, depending on the manufacturer), but I would expect to see the same thing.

Edited by Stefano, 29 July 2020 - 22:50.

[Andy Perrin]

Yeah, I should have expected the red trees since I know they reflect near IR well in addition to green and you an see them even by eye through an R72 in sunshine.