Pictorial UV

[nfoto]

I sometimes long for the UV photos to have a playful or colourful visualisation, instead of the pure technical or botanical(scientific) aspects. So let us come up with something else, and publish them here in this thread, all right?

 

My starting contribution is the following, acquired with the full-spectrum Nikon Z6, the '50s vintage lens Nikkor 8.5cm f/2, and the Baader-U filter. I shot a meadow of invasive lupines Lupinus polyphyllus. Photo Ninja nearly fell over in joy for this motif, apparently. Myself, I found the result strangely pleasant. The lens certainly is very sharp and its bokeh behaviour not usual at all. Obtaining traditional UV signatures? forget all about it.

 

[Wayne Harridge]

Really intriguing, e.g. the green areas seem to be the same sort of plant as surrounding areas, was this shot in dappled sunlight where the shadow areas and highlight areas had a different mix of UV wavelengths? Also there seem to be some regular patterned areas in the foliage which you might expect to be more random.

 

[nfoto]

This scene was captured in the autumn, so foliage had taken on a range of colours shifting from green to yellow. There are three main species present here as well, besides the Lupinus they are Solidago canadensis (another invasive plant) and Geranium sylvaticum. Plus of course a raft of grasses and undergrowth species. The conditions were diffuse overcast sunlight and I used a hand-held camera.

 

I guess my point here, apart from the wash of rich colours, is that UV has an unpredictable aspect to it. The behaviour of the lens also factors into this equation.  The old rangefinder lens, nearly 70 years old, adds its own 'drawing' to the scene. The foreground bokeh in UV breaks up the rendition in a strange fashion., whilst the background is buttery smooth (as also is the case in visible light).

[Akira]

This dandelion image is one of my earliest UV shots from 2005 (!) with D2H, Nikon Series E 28/2.8 and Kenko/Hoya U-360.  I think I didn't have Schott BG40 IR-cut filter yet.  The strong IR contamination caused by D2H's excessive sensitivity to iR "forced" me to create this UV image.    Hope it is entitled as "pictorial".

 

[nfoto]

Very pictorial, Akira.

[Akira]

7 minutes ago, nfoto said:

Very pictorial, Akira.

 

Thank you, Birna!

[Andrea B.]

Birna, the lupine photo looks like a flower field etched on a mirror or on clear ice. Or maybe like an ice crystal collage. What a fascinating presentation of a UV photo.

 

Akira, I am enjoying the play of turquoise and pink in your photo. (I loved my old D2H and missed it for quite some time after moving along the upgrade ladder.)

 

I have something to contribute, but I'll have to dig it out of one of the backup drives.

[Andy Perrin]

My very early UV photos (before joining this board, in fact) were taken in the 400-380nm range where there was not much color. I also had no access to the RAW in my CoolPix 900, or any way to change lenses at that time. I made use of the essentially monochrome images by assigning a color lookup table and making "false false colors."

 

Here is a sample of some of the nicer ones:

 

 

[photoni]

This is the ULF RAW, with Capture One everything works fine, with Photoshop it's a disaster ... so I increased the mess :)

[Akira]

On 2/23/2022 at 2:08 AM, Andrea B. said:

Akira, I am enjoying the play of turquoise and pink in your photo. (I loved my old D2H and missed it for quite some time after moving along the upgrade ladder.)

 

I have something to contribute, but I'll have to dig it out of one of the backup drives.

 

Glad you enjoy it, Andrea!  I can share the same feeling about D2H...

[Akira]

On 2/23/2022 at 5:18 AM, Andy Perrin said:

My very early UV photos (before joining this board, in fact) were taken in the 400-380nm range where there was not much color. I also had no access to the RAW in my CoolPix 900, or any way to change lenses at that time. I made use of the essentially monochrome images by assigning a color lookup table and making "false false colors."

 

Here is a sample of some of the nicer ones:

 

Andy, I like your second image.  Very mysterious and intriguing.

 

 

On 2/23/2022 at 5:49 PM, photoni said:

This is the ULF RAW, with Capture One everything works fine, with Photoshop it's a disaster ... so I increased the mess :)

 

Antonio, your image is far from disaster.  Love your choice of coloration.

[Nate]

This is one of my first UV shots back in August 2021 with a poor UV lens(canon 50mm) and a stack of UV pass filters just to block IR. 

[Akira]

This was shot around the same time I used D2H or D40, both were capable UV camera without modification.  This Fuji RTP II film could be "the" recording medium for UV images that I miss the most.  I cherished its beautiful tricolor rendition.  This image was shot using the EL Nikkor 63mm f3.5 on the Hasselblad 500C/M body and a UV-modified Sunpak flash.

[OlDoinyo]

How

2 hours ago, Akira said:

This was shot around the same time I used D2H or D40, both were capable UV camera without modification.  This Fuji RTP II film could be "the" recording medium for UV images that I miss the most.  I cherished its beautiful tricolor rendition.  This image was shot using the EL Nikkor 63mm f3.5 on the Hasselblad 500C/M body and a UV-modified Sunpak flash.

I don't know how you got chromaticity like that from RTP. My own attempts using that film were with a Minolta Autocord and a Baader U2 or B+W 403 filter and were much more monochromatic blue, unless there was substantial visible contamination (most often red.) I heard rumors that later batches of the film were more strongly overcoated, and my exposure times were quite long (I did not try flash.)

[Akira]

3 hours ago, OlDoinyo said:

I don't know how you got chromaticity like that from RTP. My own attempts using that film were with a Minolta Autocord and a Baader U2 or B+W 403 filter and were much more monochromatic blue, unless there was substantial visible contamination (most often red.) I heard rumors that later batches of the film were more strongly overcoated, and my exposure times were quite long (I did not try flash.)

 

I was interested in this RTP II film after I saw then-Bjørn's images shot with RTP (as you would):

 

http://www.naturfotograf.com/UV_POTE_ERE.html#top

 

I didn't have the FF filter accompanying UV-Nikkor (I suspect that was Hoya U330) but found the way to order Hoya U360 in the 52mm filter ring which I used to the crucifer image posted here.  U360 does have a light leak in the 700-800nm range with the peak at 750nm, but RTP II is not sensitive enough to respond to that range, according to its spectral response.

 

As you would know, the B+W 403 uses Schott UG1 glass whose transmission curve is similar to that of Hoya U330.  It has much more leak in the deep red range than U360.  So, I'm afraid I have no idea where the red and white (even blue-ish) color in my image came from...

[OlDoinyo]

Some of my examples of hybrid images with the red contamination are this one (403) and this one (Baader, with the sun punching through in the red.) I often got red-looking foliage, even though the film has no IR sensitivity, such as seen here. But all these had very aggressive color balancing in Photoshop. Without that, they tended to look like this one. I did not attempt flowers much with that camera as it was not much suited to it; but the white petals with magenta centers does not look anything like what I believed I could do.

 

 

[Akira]

22 hours ago, OlDoinyo said:

Some of my examples of hybrid images with the red contamination are this one (403) and this one (Baader, with the sun punching through in the red.) I often got red-looking foliage, even though the film has no IR sensitivity, such as seen here. But all these had very aggressive color balancing in Photoshop. Without that, they tended to look like this one. I did not attempt flowers much with that camera as it was not much suited to it; but the white petals with magenta centers does not look anything like what I believed I could do.

 

 

 

The image at the third link with foliage rendered in red looks interesting.  In the landscape images, it would be difficult to make sure which surface of an object shows the reflection in UV, especially with the filter with that much leaks in the visible range like 403.

 

On the contrary, the "bull's eye" pattern of the cruciferous flower is the telltale sign of the UV reflection.  That's why the cruciferous flower is one of the most reliable targets to check out the UV capability of the cameras, lenses, filters and flashes.  I also shot Oenothera which also shows beautiful UV pattern in the central area of the flower which is also rendered in red on RTP II.  I have yet to digitize the Oenothera images.

 

Have you shot any closeups of the flowers with RTP?

[nfoto]

Just for the record: far from every yellow-flowered cruciferous species will show  a  'bull's-eye' UV signature. In fact, many will be more or less dark all over their petals. Even for those species with a UV-dark centre, there can be very prominent UV-dark veins on the petals. The sepals can sometimes be entirely UV-black.

 

The genus Barbarea (Wintercress) do have the nice 'bull's-eye' signature in UV. They are widely distributed and invasive species in many parts of the world, thus good candidates for UV photography. Likewise some -- but not all -- species in the genera Sinapis, Brassica, and Raphanus have a similar UV response.

[Andy Perrin]

Do we know anything at all about why the yellow flowers in particular tend to have the bullseye more frequently? Or why the other colors don't usually?

[nfoto]

I'm not convinced there is such a general tendency. As in the case of the Cruciferae (Brassicaceae), many yellow-flowered species of Asteraceae, Fabaceae, and other large families tend to be dark or even totally black in UV.

[OlDoinyo]

On 4/2/2023 at 1:09 PM, Akira said:

Have you shot any closeups of the flowers with RTP?

Not with RTP. I did shoot one shot with Rudbeckia in it with Aerochrome.

 

In the hybrid images, the red light is much more specular and less diffuse than the UV, which leads to an interesting effect in images such as the one from the cemetery.

[lonesome_dave]

I'll add a couple false color UV images here.

A few months ago I was showing someone how to use Photoshop Elements and messed with a couple of my UV photos.

I decided to make the vegetation look normal and see what happened to the rest. I chose a white balance target, then just used the Hue & Saturation controls to get the vegetation about the same green as it appears visually. I wrote down Hue+60,Sat+18 after WB. Gear was Sony A6000 FS, Sirchie 60mm Quartz, Baader-U.

 

In the image above the car and flat rooftops were visually white. Initial WB was on the concrete around the car. Looks like the paint on the car & house in addition to the foam roof material absorbed a lot of UV.

 

Same adjustments here. UV and false color turned a crystal clear day into a toxic-looking smoggy mess.