Jump to content
UltravioletPhotography

Red Eyed Susan?


Cadmium

Recommended Posts

I don't have any other wavelengths. Just the MTE Nichia 365nm (typically used for UVIVF).

The GG420 was stacked with Baader UV/IR-Cut filter on the lens. I also shot it with BG38, BG40, and Baader UV/IR-Cut which was the reddest of the three, so that is the one I am showing above.

Link to comment

Andy, That is an outrage! Maybe they copied it from me! ;-)

 

Here are some I did using a stock D610, no filters on the lens, just a Hoya U-340 2mm thick filter on the MTE's. I used two MTE's with these shots to get the lighting more even.

Visual is just a plain overhead room light. By the way, these fluorescence shots look pretty much exactly the way they did to my eyes, colors and hidden patterns, so it would seem these hidden patterns are shown via fluorescence, not just in UV, because I could definitely see the same patterns with my eyes.

 

post-87-0-92288500-1473499615.jpg

 

post-87-0-97853100-1473499629.jpg

 

post-87-0-46848800-1473499640.jpg

Link to comment

Just a common imposture, I think.

 

I will try looking at the Rudbeckia through GG420 tonight to make sure my eyes and my camera are not seeing some kind of partial UV pattern,

but this pattern seems to be from fluorescence alone.

Link to comment

Andrea, Yes that would be welcome and interesting to see, whenever you like. :)

 

Here is a comparison of the Rudbeckia. Visual, 850nm IR LUM, and 850nm IR.

LUM = luminescence. Or otherwise known as visual induced infrared fluorescence (VIIRF)

Using green light to induce the IR LUM. This requires very long exposure time using the small light source I used.

post-87-0-68311500-1473656517.jpg

Link to comment

Here is a 365nm UV induced 850nm IR Luminescence shot.

Illumination for the LUM shot was two MTE 365nm torches, both filtered with U-340 2mm.

The camera lens had a Schott RG850 (850nm IR longpass) filter on it.

Pretested: Shinning the filtered MTE light directly into the 850nm filtered lens, no light was detected in live view.

What we see here is UV induced IR luminescence. The Rudbeckia is not illuminated with any IR light, no reflected IR light.

This was shot in total darkness, except for the 365nm UV MTE light.

post-87-0-18421400-1473754421.jpg

 

post-87-0-43062700-1473754437.jpg

Link to comment

Col, Thank you :-) I am only experimenting with fluorescence and LUM in this set, so I don't have any UV-only shots, sorry. :-(

Here is a desaturated comparison set. All these shots are desaturated, except the color UVIVF shot in the upper center.

This mostly helps me to compare the UVIVF, VIIRF, and the UVIIRF shots to each other.

These are not all shots of the exact same flower, but these seem to suffice.

One thing to note is the lack of 'pattern' shown in the desaturated version of the UVIVF as compared to the color version.

post-87-0-24478400-1473771931.jpg

Link to comment

Very interesting work! Thanks for posting this.

 

The UVIVF desat does show the bright tones of the fluorescence on anthers of the small disc flowers. So I suppose it is not completely "pattern-less". :)

 

Providing B&W versions is very useful to help show the fluor versus non-fluor areas. Or the UV-absorbing versus UV-reflective areas. And so forth.

 

The lower left VIIRF is quite striking in B&W.

Link to comment

Very interesting work! Thanks for posting this.

 

The UVIVF desat does show the bright tones of the fluorescence on anthers of the small disc flowers. So I suppose it is not completely "pattern-less". :)

 

Providing B&W versions is very useful to help show the fluor versus non-fluor areas. Or the UV-absorbing versus UV-reflective areas. And so forth.

 

The lower left VIIRF is quite striking in B&W.

 

The lower left VIIRF *is* black and white, given it is 850nm IR. That shot is already desaturated be default via white balance (although it can be desaturated, but no change really).

Mostly I was comparing the UVIVF to the UVIIRF, they seemed to have about the same pattern, so I desaturated the UVIVF color version to compare it to the already (850nm) monochrome UVIIRF image,

however they are not the same once desaturated.

Partly what I was concerned with there is the possibility of residual visual fluorescence 'leaking' into an IR fluorescence shot.

In other words, could the UV induced IR fluorescence shot be contaminated by visual fluorescence by way of longer exposure.

I am still testing that idea, but so far it doesn't look like that was the case.

Link to comment

The lower left VIIRF *is* black and white, given it is 850nm IR.

 

oh yeah!!! :lol: :lol: :lol: So it is.

Anyway I really like that one with the very black flower.

Link to comment

Thanks Steve

No preference, just a UV mono shot of this flower to compare the UV pattern with the other mono patterns.

I guess the MTE will be ideal.

Col

Link to comment

Here are two UV 365nm MTE illuminated Rudbeckia shots. These were light painted with two torches at the same time, so there are some variations in lighting, etc..

Both were the same color, almost monochrome, I have desaturated each here.

La La U (OD5v, left), Baader U (right).

post-87-0-54470700-1473841803.jpg

Link to comment

Hi Clark, I don't know. In that example just the foliage is glowing, and nothing else to compare to.

A friend of mine has been doing a lot of this, so it has sparked my interested in trying it out.

This was my first experiment with IR LUM using a flower. I did some tests before with ceramic cadmium pigments, which glows much stronger than the Rudbeckia foliage does.

When I was doing the Rudbeckia, I had to pull out the cadmium stain to double check, because the 'glow' level I was getting from the Rudbeckia was not what I remembered with the cadmium, indeed this was true.

It becomes quite apparent to me that I need a much stronger green light source than I am using, which is only a flashlight filtered with visual/green only filters, and I have to moved the light to 'paint' the target.

There are many flood style green LED lights for sale online, and one or two of those would have a lot more light and make things better. Those lights would probably still need to be filtered to make sure they don't leak some IR light. Just like with UVIVF it is important to separate the excitation light from the 'glow band'.

I imagine that IR fluorescence ('IR LUM') is similar to visual fluorescence, and that many things in IR fluoresce, but something do more than others, and some things don't.

You know how some things fluoresce brightly in UVIVF, and how if you remove those things, other things fluoresce also, but not as brightly.

So it would seem that IR LUM is a similar scenario.

 

I tried the 850nm IR LUM first, but tonight I am going to drop down to 720nm and even 610nm, which I expect might have a little visual contamination, because my light filter is close to 600nm cutoff.

So it will be a mix, but what I have seen has a very surreal effect. Which is being called The Pandora Effect.

I started with 850nm to give myself a solid 'non-mixed' reference for the 610nm, etc..

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...