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willow pond - UG2a

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#1 bobfriedman

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Posted 08 June 2019 - 00:51

Nikon D800 ,AF-S NIKKOR 16-35mm f/4G ED VR ,UG2a
1/125s f/8.0 at 16.0mm iso125
Posted Image

Nikon D800 ,AF-S NIKKOR 16-35mm f/4G ED VR ,UG2a
1/125s f/8.0 at 16.0mm iso12
Posted Image

#2 Cadmium

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Posted 08 June 2019 - 03:45

Looks good!

Edited by Cadmium, 10 June 2019 - 04:45.


#3 JMC

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Posted 08 June 2019 - 07:51

Those are beautiful. I especially like the first one.

#4 Andy Broomé

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Posted 08 June 2019 - 14:31

Interesting how the sky is blue, yet the water is black. Did you desaturate the water in post processing, or is it like this out of camera?

#5 bobfriedman

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Posted 08 June 2019 - 16:09

View PostAndy Broomé, on 08 June 2019 - 14:31, said:

Interesting how the sky is blue, yet the water is black. Did you desaturate the water in post processing, or is it like this out of camera?

you can consult Cadmium on the UG2a filter spectrum but it passes blue/violet.. at least enough to get the blue sky.. it excludes the rest of visible and passes IR.

#6 Cadmium

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Posted 09 June 2019 - 03:58

Here is a newer comparison graph, starting with UG1, which is the age old favorite dualband IR filter, then the newer UG2A (which by the way UG2A was discovered for the UV/IR crowd by Ulf),
and also UG5 (U-330) to show how the UG2A 1mm starts to look similar.
Again, I have so far not compared UG2A 1mm with UG2A 2mm. I have compared UG2A 2mm with the others, and with U-360 which could just as easily be on this comparison graph along with the rest of these filters,
but given that Bob has experience with UG1 instead of U-360, and there is only so much room on the comparison graph to compare the lines easily,
I decided to compare to the UG1 which has more complete full range data than Hoya glass does.

Here are my thoughts.
In a UV stacking scenario, any little bit of transmission above the 1E-03 line would make a difference and show up in the color palette of the photo.
However, with dual band IR, given the overpowering IR content, I rather doubt that the small amount of green will be showing in the mix.

So more realistically, used as a dual band IR filter, here is probably about what you get with these three filters. I am basing these estimates on 1% transmission (0.01 on graph) instead of 1E-03.
UG1 2mm (blue line) transmission up to 400nm
UG1 1mm (red line) transmission up to 410nm
UG2A 2mm (purple line) transmission up to 420nm
UG2A 1mm (amber line) transmission up to 440nm

Also, take a look at the Red/IR threshold. Keep in mind that with each of these you are not only adding to the violet transmission end, but you are also adding more Red/false color IR to the IR end.
I can't think of any examples of that in photos, just something to think about.

Here is the graph, you can decide what you think.

Attached Image: UUG2A_1mm_2mm_Others.jpg

Edited by Cadmium, 10 June 2019 - 04:46.


#7 bobfriedman

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Posted 09 June 2019 - 17:55

yep.. for what I do.. better off with UG2a at 2mm. I just want blue + IR and the lenses I use for scenery don't pass much UV if any.

#8 Cadmium

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Posted 10 June 2019 - 04:47

Yet your lenses work with UG1 2mm.

Edited by Cadmium, 10 June 2019 - 11:35.