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The first to bloom

Multispectral
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#1 Mark

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Posted 15 April 2017 - 15:09

I'm not sure what these are, as the previous owner of this house planted them in the front yard long before I got here. These were the first to bloom that I can see around my neighborhood - a welcome new subject after a long winter.

In this multispectral set I tried using multiple UV sources, just out of curiosity to see what the end result might look like. To this end, the UV and UVIVF images below were irradiated with:
  • from the left hand side: MTE-U303 torch + U340 filter
  • from the right hand side: 40 x LED torch (4 banks of 10 LEDs @ 365/375/380/390nm) + B&W 403 filter
  • from above: 4 x 18" T8BL-B + 2x FL20 filter glass
I also included a PTFE disc for white balancing, within frame but just out of my intended crop area. This worked well for WB operations on all of the images below.
Attached Image: 04-12-2017_19-54-11_ptfe.jpg

Using an off-camera flash to illuminate, the VIS image was easy to white-balance thanks to the PTFE:
Attached Image: 04-12-2017_19-36-41_vis.jpg
Lens filter: 425 nm longpass + GG435 longpass + 2" Baader UV/IR block

Using multiple UV sources lead to at least one interesting effect. The MTEU303 torch produces a strong gold colored image, as compared to the fluorescent bulbs or the 40xLED torch (I verified this in other shots, shooting under each source separately). In this scenario the gold color is cast as a highlight (from the left where the MTEU303 was). It actually took a bit of work in PP to get the gold cast under control, but I think I ended up with a nicely exposed image - which has a sort of wet, metallic look I really like.
Attached Image: 04-12-2017_19-36-41_uv.jpg
Lens filter: Asahi ZRR0340 UV-pass

I had hoped for a much stronger UVIVF image result than this, since I was dumping so much UV into the scene. But, I understand it could just be that this flower just doesn't have much of a fluorescent display, aside from the soft reds in the petals, and some light from the pollen. Of course, the lint in the background is doing its thing, as always!
Attached Image: 04-12-2017_19-36-41_uvivf.jpg
Lens filter: 425 nm longpass + GG435 longpass + 2" Baader UV/IR block

The IR view is rather unremarkable (IMO), aside from one thing - the anthers are very, very IR reflective. I just couldn't get any signal back on those anthers in PP (not even from the RAW original). They are completely blown out. I wonder, in regard to the workings of nature, if this is coincidental.
Attached Image: 04-12-2017_19-36-41_ir.jpg
Lens filter: Hoya R-72; incandescent illumination

Mixed in with these flowers are some of what look to be the same, except they are purple colored - so I shot these as well, just to see if the VIS coloration had any link/association with UV/UVIVF/IR results. Shown here in VIS, the petals look structurally the same - but I'll note that when I clipped the stem of the flowers above, it was hollow; when I clipped the stem of these flowers, it was solid/full. So maybe they are different species?
Attached Image: 04-14-2017_20-31-25_vis.jpg
Lens filter: 425 nm longpass + GG435 longpass + 2" Baader UV/IR block; flash illunination

It was harder to get the color balanced in PP for this UV image - for some reason that gold cast from the MTEU303 was more prominent (maybe because I was physically closer this time?). Either way, that wet, metallic look is still there, and I like that.
Attached Image: 04-14-2017_20-31-25_uv.jpg
Lens filter: Asahi ZRR0340 UV-pass

This subject produced a similarly colored UVIVF result, but with some subtle differences - for example, the anthers here also fluoresce but not nearly bright enough to illuminate their immediate surrounding area, as in the example above.
Attached Image: 04-14-2017_20-31-25_uvivf.jpg
Lens filter: 425 nm longpass + GG435 longpass + 2" Baader UV/IR block

In the IR image I opted this time to keep the natural hues generated by the R72 filter. Sometimes I like the color, other times I want only the luminosity of the image (grayscale). I don't know, maybe it just depends on how much coffee I've had (I was well caffeinated by this point).
Attached Image: 04-14-2017_20-31-25_ir.jpg
Lens filter: Hoya R-72; incandescent illumination

I just noticed this morning that there are now pink/red versions of this flower also popping up. Maybe those are hiding something unexpected...

#2 nfoto

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Posted 15 April 2017 - 16:31

Something from the Liliales order of the monocots. Might be a Hyacinthoides, but we need to see foliage and better floral details.
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#3 Andrea B.

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Posted 15 April 2017 - 23:27

From the color range, floret appearance and general stalk shape, these are hyacinths (genus Hyacinthus). There are different types and a gazillion cultivars. Some love the fragrance, others think they smell like dirty socks. :D

This wet, metallic look in UV is quite interesting. I wonder if a close, close-up would reveal any conical cells which can cause this kind of iridescence.
Andrea G. Blum
Often found hanging out with flowers & bees.

#4 Mark

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Posted 16 April 2017 - 01:31

Wow Andrea - good call! I just checked wikipedia, and yes - that's exactly what they are - thanks :)

#5 nfoto

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Posted 16 April 2017 - 07:19

View PostAndrea B., on 15 April 2017 - 23:27, said:

... This wet, metallic look in UV is quite interesting. I wonder if a close, close-up would reveal any conical cells which can cause this kind of iridescence.

This is observed with other species in the Liliales as well. For example, Scilla, Puschkinia, Hyacinthoides, to name a few I have photographed over the years. In contrast, I have never seen this appearance for Gagea which also systematically belongs in the same group.
Bjørn Birna Rørslett