Assorted flower Infrared Fluorescence

[Andy Perrin]

I went back to the Community Garden at midnight armed with my Sony A7S conversion, the Sony FE 1.4/24 GM lens, and a Hoya 25A filter (long pass starting around 600nm - a red filter) and my Nemo torch for some UV-induced infrared fluorescence (UVIIF).

 

Sunflower with a sleepy pollinator (all these photos have been white balanced to remove the strong color cast, and street light IR has been subtracted off)

 

1-1 crop

 

Assorted flowers and a stripped insect

 

 

 

 

[lukaszgryglicki]

Really nice fluorescence images, I just can't see 1st one...

 

[Andy Perrin]

Refresh, I just changed it to a higher resolution copy.

[colinbm]

I like the different colours

[Doug A]

Colors are a lot different than UVIVF. I like these IR renditions. 

Thanks for sharing,

Doug A

[Nate]

Cool images Andy, I keep forgetting to try this

[Andy Perrin]

Thanks all, just added a couple of new ones at the end of the original post.

 

A couple of thoughts:

1) I used a Red 600nm filter instead of a 720nm cutoff because I wanted more color in the images

2) Even so, even after subtracting background lighting and white balancing to remove the cast, I still had to push up saturation quite a bit to see decent colors. These should certainly be regarded as "false color" images, despite some visible light fluorescence being included in addition to the IR.

[photoni]

Good @Andy Perrin  these images are also very beautiful and interesting.
What was the reason for using a red filter instead of a UV filter or a yellow ?

[Andy Perrin]

I had already done a yellow filter (Haze 2E) previously, this was to capture primarily the INFRARED fluorescence (UVIIF). As I said in the post directly above yours, I put the cutoff at 600nm to retain a bit more color in the final images — as you know, the further one goes into IR, the more monochrome the results. This is due to the Bayer dyes becoming transparent.

[photoni]

now I have a little devil in my brain that thinks ...

I have to try to photograph the hibiscus with Nemo and all the filters in the house :-))))

[KhanhDam]

very nice. Never even knew light flouresces into the ir range. 
I've noticed many flourscent photography has a black background which makes them look similar. you could try getting a scrap of white tyvek. it might make a nice change of background. I'm guessing it would come out as a white or pinkish tone in this applicaiton.  and you can just stuff it into a bag when done.

[Andy Perrin]

In fluorescence photos, typically the only light is provided by the glowing flowers or other objects and that is why the background is black. There is nothing but the objects in the scene glowing to provide illumination. Putting a screen behind them might result in some reflected light from the flowers but it wouldnt be a white or even pink background unless additional ambient light was added, which reduces the colors in the fluorescence. Also the screen itself would have to be made of a material that does not fluoresce or it would wipe out the image by glowing too much. I get the idea you haven’t tried this yourself yet!

[dabateman]

Or just grab that black baground in photoshop and paste in a blackdrop with volcanoes and giraffes. 

Andrea added some nice giraffes in IR with luminar I think.

[Andy Perrin]

I have read that pasting in skies is considered unclassy in photography circles these days!

[photoni]

12 hours ago, KhanhDam said:

very nice. Never even knew light flouresces into the ir range. 
I've noticed many flourscent photography has a black background which makes them look similar. you could try getting a scrap of white tyvek. it might make a nice change of background. I'm guessing it would come out as a white or pinkish tone in this applicaiton.  and you can just stuff it into a bag when done.

you could try with
solarized
effect Sabattier
Armand Sabattier
solarization curves
pseudo solarization
... with photoshop

.

[Andy Perrin]

[KhanhDam]

16 hours ago, Andy Perrin said:

….unless additional ambient light was added, which reduces the colors in the fluorescence. Also the screen itself would have to be made of a material that does not fluoresce or it would wipe out the image by glowing too much. 

I’ve done it with black lights.  Yes you are correct you have to use a back ground that fluoresces or is visible in the spectrum you are using.  Just like regular photography the light falls off the further the background is behind the subject.and yes one can use a second light too if desired.    If you are using anything white with red filter it will be pinkish.  Use grey or dark grey if one wants redder color or adjust background distance.   It won’t wipe out image if done correctly and I’ve never experienced that either

[Andy Perrin]

No, this is FLUORESCENCE not reflected light photography. The UV illumination is by definition in a different spectrum that is blocked by the IR filter on the camera. The camera does not see the UV light. The problem is not that the light falls off with distance. The problem is that the scene light comes from the flowers themselves. 
 

If you still think I’m wrong then don’t reply with theories, instead take some photos showing how you think it should work. I am not interested in any more theories in this topic. 

[Wayne Harridge]

Really interesting images Andy, I like the colour palette.

A question:  Does the IR fluorescence change with the wavelength of the exciting UV and can you get IR fluorescence using visible light?

 

 

[Andy Perrin]

Yes to both probably. Colin showed that UV-B and C make rocks glow differently in visible, and others have shown that green visible light can make IR fluorescence. 

[Andrea B.]

I have read that pasting in skies is considered unclassy in photography circles these days!

 

However, giraffes are permitted, even encouraged by some photography authorities.

---

 

 

Andy, I just now saw these. Sorry to be so late responding. They are really quite beautiful in an IR fluorescy way. 

 

We've all had a lot of debate about "proper" white balance for uv-induced visible fluorescence. I can guess how crazy a discussion about "proper" uv-induced infrared fluorescence would be. 

 

BTW, lurking in community gardens at midnight with strange gear and odd lights......we need to get you some kind of photographer's vest with an UltravioletPhotography.com logo on it. Fluorescent, of course.

[Andy Perrin]

Haha, they are COMMUNITY gardens, not private ones.

[Craigo79]

Very nice results