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Oncostele orchid with two UV filters

Dr Klaus Schmitt

Well-known member
Well, this one is a bit technical: I wanted to show the difference of a well working and not so well working filter for reflected UV photography.

168525420.EuEaMByn.jpg


Left is my "work-horse" the Baader-U Venus filter, right a rather new one, the Optolong Venus-U filter.

Same equiment otherwise: converted Panasonic GH4, UV-Nikkor 105mm at f8, Xenon studio flash (modified for hight UV output)

Guess I don't need to say much, the central flare and near IR leakage is very prominent....

But quality comes at a price as we all know, don't we?
 

Asher Kelman

OPF Owner/Editor-in-Chief
Well, this one is a bit technical: I wanted to show the difference of a well working and not so well working filter for reflected UV photography.

168525420.EuEaMByn.jpg


Left is my "work-horse" the Baader-U Venus filter, right a rather new one, the Optolong Venus-U filter.

Same equiment otherwise: converted Panasonic GH4, UV-Nikkor 105mm at f8, Xenon studio flash (modified for hight UV output)

Guess I don't need to say much, the central flare and near IR leakage is very prominent....

But quality comes at a price as we all know, don't we?


But like a cheaper date, thrill might come easier!

At a cost, LOL!

From the esthetic standpoint, the leakage does make for a prettier flower for our, (albeit limited), human perception! We would have to remove that dull abandoned-military-bunker hue of the b.g., but then that flower would be wonderful. I would love to see that in comparison with the same UV Nikkor without the filter!

Asher
 

Asher Kelman

OPF Owner/Editor-in-Chief
Guess I take this as a joke Asher... ;-)

I wrote about that here in more detail: https://photographyoftheinvisibleworld.blogspot.com/2018/12/baader-u-venus-filter-versus-optolong.html

I made several logical errors. I meant to compare the leaky filter image with that from an ordinary visible light optic with a non-modified sensor.

On first impression, I like the pastel colors on the second “leaky” filter and the absence of the deep black areas. However, as you point out, these pretty pastel areas have much less contrast than in the picture with the Bader filter.

So, to generate something “prettier” to the human brain I would work with the Bader filtered image as it is far higher quality and one could select regions by luminance and color and getca wonderful result tuned to “expectations” of human experience with flowers of this lilac color.

Asher
 

Asher Kelman

OPF Owner/Editor-in-Chief
Sure that could be done!! I do my work when I press the shutter though....just my personal preference.

Yes, that’s an ideal way of working, Klaus. I think that’s the discipline Nicolas Claris, Jim Galli and Maris Rusis use, and they are the best!

I am a “constructionist”. Hardly anything is accidental in my photography. Much of my work is planned, but thefinal shutter release is impulsive. Outdoors, grabbing adjacent frames is normal. I learned that from cinematography crews filming in my house for a TV series on architectural styles in the USA, “Dream Living”.

In addition to the list of shots of what they “want” and “need”, they always take, “coverage”, adjacent overlapping images so they can plan from a new beginning at time of editing.

So I look at photography from this “second class” perspective of “building an image” once I get to see the shoot on my color-corrected monitor in my dim-lit studio.

So looking at your pictures, I am also wondering how I would integrate your beautiful
UV-reflected light images into my much larger compositions.

I am fascinated by the subtle differences that reflected UV light can show in a photograph we are used to seeing in visible light.

I have developed for myself, what I call “centripetal learning”. I wonder away from my own core project and lounge around in other people’s works, asking myself,

“In what way can I learn to express myself better or meet my challenges using the insights gleaned from all the intense efforts made in what is on first consideration, nothing to do with my work?”

I have learned a lot that way.

I do not as yet know how to exploit UV filters ...even leaky ones, in my work, but this opens the door to such a lot I could learn.

Eventually something will “click” and my functionality increases a tad!

So thanks for your indulgence!

Asher
 
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