The Invisible Light That Plants Emit

[David H. Hartman]

I use a 365nm UV torch called Tank007 bought from ebay to induce the visible fluorescence.  The torch emits a slight amount of visible light which is cut by a Baadar U (UV bandpass) filter.  You need nothing special on the camera or the lens, not even L37/39/41C filters, so long as the UV light source contains no visible portion, and you take the pictues in the total darkness.

Here's another humble example: UVIVF Oncidium.

Akira, can you be more specific? I'm not sure which mode flashlight one should buy and I'm looking at fillers that coast $300.00 to $400.00 (USD). This is a fright fest!

Dave Hartman

[Akira]

Hi! So we need to use the filter on the UV light? I put it on the lens... And my filter is a IR filter. The filter must be UV, not IR? Sorry, I don´t understand these things very well... And the UV light must be invisible? The one I bought is invisible during the day, but at the dark I can see the "blue light". So this one can`t be used? (Sorry for any English`s mistake, I speak portuguese)

Hi, Castorelle.  Welcome to NG.

First of all, you need to understand that UV induced visible fluorescence and photographing reflected UV are two completely different worlds.

In this thread, we are talking about UV induced visible fluorescence.  That means, the UV light is used to induce the fluorescence.  UV light is invisible but the induced fluorescence is visible.  All images posted in this thread are the captures of visible image.

On the other hand, something like the "bull's eye" pattern of the flower belongs to the reflected UV photography.  The captured image is invisible.

So, you need very different equipments for each.  In order to capture the images posted here (UV induced visible fluorescence), you need:

1. A UV flashlight (you already have an appropriate one).
2. Either one of these:
2a. A special filter that passes only UV light (around 365nm) which should be put on the flashlight.
2b. A light yellow filter (Y44 or similar) to cut the visible portion of UV flash light which should be put on the camera lens.

An IR filter is not needed or makes no sense in any way, so long as you use UV LED flashlight as a light source.

If you go for the option 2b, the color of the fluorescence may not be the same as you would see with the naked eye.  The blue fluorescence wiil turn to green.

[Akira]

Akira, can you be more specific? I'm not sure which mode flashlight one should buy and I'm looking at fillers that coast $300.00 to $400.00 (USD). This is a fright fest!

Dave, the UV flashlight I bought from ebay is "TK566" by Tank007 (sorry Tank007 seems to be the name of the brand and not the model name).

The UV bandpass filter I use for the flashlight is the 1.25" Baader Venus U filter made by Baader Planetarium:

http://www.baader-planetarium.com/de/u-venus-filter-(350nm).html

[Øivind Tøien]

I really love the images in this thread. Akira, do you have the long version of the flashlight or do you find that one AA battery version is enough?

Those Venus filters are really pricey...  Which size filter fits the flashlight? Somewhere I have a blacklight (Mineralight) that I saved from being thrown away. While the wavelengths of UV from that light might be unhealthy and the batteries are dead, perhaps the filter could be used.
Finding a dark place around here at this time of the year can be a challenge though... Perhaps a small dark box could be constructed.

Any good source of UV-protective glasses?

[David H. Hartman]

Akira,

Thank you for the information. I'll check it out soon.

Dave

[Akira]

I really love the images in this thread. Akira, do you have the long version of the flashlight or do you find that one AA battery version is enough?

Those Venus filters are really pricey...  Which size filter fits the flashlight? Somewhere I have a blacklight (Mineralight) that I saved from being thrown away. While the wavelengths of UV from that light might be unhealthy and the batteries are dead, perhaps the filter could be used.
Finding a dark place around here at this time of the year can be a challenge though... Perhaps a small dark box could be constructed.

Any good source of UV-protective glasses?

Øivind, my TK-566 is the longer version that uses two AA batteries.  I haven't used the one AA version, but I think the stronger the better, so long as you compare these particular ones.  Needless to say, the the longer version is more powerful and can induce the fluorescence more easily.

The Baader Venus U filter (even the smaller, 1.25" version) is indeed pricy.  I was just lucky enough to receive mine from my UV friend "V" as recompense for my effort to find and send him some items only found in Japan.

The 1.25" filter doesn't fit directly on TK-566, and I found a 31.7mm (1.25") to C mount adpter by BORG whose C mount hole fits right onto the head of the flashlight.  I fixed the adapter to the flashlight with the self-adhesion tape.  This is the adapter:

http://www.tomytec.co.jp/borg/products/partsDetail/summary/238

That said, the hindsight tells me that I could simply fix the filter onto the flash head with the black Permacel tape.

As for the UV protection, I use UVEX 9195 999 goggle.  It looks transparent, but it can completely block the fairly strong TK-566 light.

Hope the info would be of any help.

[Andrea B.]

Nikongear's "Sister Site":  UltravioletPhotography.com has some info about UV-induced visible fluorescence photography which might be helpful.

Short Intro to UVIVF:  <> Sticky :: UV-Induced Visible Fluorescence <> by Andrea B.

Photo Board: UV Fluorescence & Luminescence
A post by Alex Holovachov:  My UVIVFL journey
Damon's fluor mushrooms: Mushrooms and friends

Article: Examples of UV-induced Fluorescence by our very own Bjørn-Birna Rørslett

WB Target: I'm just now testing a new standard target for making an in-camera white balance setting under UVIVF conditions. Experiment 1: First Look at Target-UV & UV-Grey for U...

Sticky:  Everything you ever wanted to know about UV/IR filters and then some: <> Sticky :: UV/Vis/IR Filters <>

Tag Search: All posts about UV illumination (some about UV-flash and some about UV-Led flashlights/torches): UV Lighting

UV-Induced Visible Fluorescence of Satsuma Tangerine under Blacklight
f/11 for 3" @ ISO-400 in Darkness
The 2nd foto is a close-up of the tangerine's skin.

[Castorelle]

Hi, Castorelle.  Welcome to NG.

First of all, you need to understand that UV induced visible fluorescence and photographing reflected UV are two completely different worlds.

In this thread, we are talking about UV induced visible fluorescence.  That means, the UV light is used to induce the fluorescence.  UV light is invisible but the induced fluorescence is visible.  All images posted in this thread are the captures of visible image.

On the other hand, something like the "bull's eye" pattern of the flower belongs to the reflected UV photography.  The captured image is invisible.

So, you need very different equipments for each.  In order to capture the images posted here (UV induced visible fluorescence), you need:

1. A UV flashlight (you already have an appropriate one).
2. Either one of these:
2a. A special filter that passes only UV light (around 365nm) which should be put on the flashlight.
2b. A light yellow filter (Y44 or similar) to cut the visible portion of UV flash light which should be put on the camera lens.

An IR filter is not needed or makes no sense in any way, so long as you use UV LED flashlight as a light source.

If you go for the option 2b, the color of the fluorescence may not be the same as you would see with the naked eye.  The blue fluorescence wiil turn to green.

Thank you a lot Akira!! So I made a great confusion with IR and UV photography ...

The photos I want to take are just like the ones are posted here, but I thought it had another name, with the word "IR". Now that I know the correct name (UV induced visible fluorescence) it will be easier to search informatition for learning more about it.

I will buy this special filter for the flashlight, you said at 2a.
Thanks again!

[Castorelle]

Nikongear's "Sister Site":  UltravioletPhotography.com has some info about UV-induced visible fluorescence photography which might be helpful.

Short Intro to UVIVF:  <> Sticky :: UV-Induced Visible Fluorescence <> by Andrea B.

Photo Board: UV Fluorescence & Luminescence
A post by Alex Holochov:  My UVIVFL journey
Damon's fluor mushrooms: Mushrooms and friends

Article: Examples of UV-induced Fluorescence by our very own Bjørn-Birna Rørslett

WB Target: I'm just now testing a new standard target for making an in-camera white balance setting under UVIVF conditions. Experiment 1: First Look at Target-UV & UV-Grey for U...

Sticky:  Everything you ever wanted to know about UV/IR filters and then some: <> Sticky :: UV/Vis/IR Filters <>

Tag Search: All posts about UV illumination (some about UV-flash and some about UV-Led flashlights/torches): UV Lighting

UV-Induced Visible Fluorescence of Satsuma Tangerine under Blacklight
f/11 for 3" @ ISO-400 in Darkness
The 2nd foto is a close-up of the tangerine's skin.

Andrea, very good stuff!! Lots of things to read! Thank you!! And it's a good idea to photograph fruit. I will try too!

[Øivind Tøien]

Thanks Akira and Andrea for further information. This is becoming a nice thread for reference. I might just get the flashlight (and UV goggles!) and experiment with the filter from the old Mineralight.

[Akira]

Here's an image of the removed flashhead of TK-566.  The silver ring around the thread is the bottom part of the BORG adapter I mentioned above.

[Øivind Tøien]

Thanks for posting the image Akira,
I ordered this 20mm filter at $8 on ebay that as a start can be taped to the front of the TK-566. The spectrum (red line in the link) looks promising:
http://www.ebay.com/itm/262986004673

(The filter of the Mineralight let though violet light from a regular LED flashlight)

[Frank Fremerey]

LWUV-induced resonance fluorescence

Stunning Results!!!

[Akira]

Thanks for posting the image Akira,
I ordered this 20mm filter at $8 on ebay that as a start can be taped to the front of the TK-566. The spectrum (red line in the link) looks promising:
http://www.ebay.com/itm/262986004673

So long as the chart is trustworthy, ZWB1 seems to work (looks like Hoya U340 equivalent).

[Øivind Tøien]

Time will show once everything arrives. In the mean time, with 24h daylight here at this time of the year I wonder if something like a large changing bag, with a homemade  internal frame added could be used instead of the non-existing dark closet in my cabin (could also be used in the field). For example:
https://www.bhphotovideo.com/c/product/70983-REG/Kalt_NP10102_Large_Changing_Bag_Double.html
The lens would be stuck through one of the arm holes. perhaps the other arm hole can be used for a cable switch for the framing/focusing light that would have to be mounted inside. Have anyone here played with something like this who would like share their experiences?


[Kalt Large Changing Bag Double Zipper (27 x 30")]