• Ultraviolet Photography

Helianthemum nummularium ssp. obscurum [Common Rock-rose]

2 replies to this topic

#1 nfoto

    Former Fierce Bear of the North

  • Owner-Administrator
  • 3,256 posts
  • Location: Sørumsand, Norway

Posted 01 July 2014 - 10:00

Rørslett, B. 2014. Helianthemum nummularium (L.)Mill. ssp.obscurum (Čelak.) Holub (Cistaceae). Common Rock-Rose. Flowers photographed in visible and ultraviolet light. http://www.ultraviol...mmon-rock-rose/

Helianthemum nummularium (L.)Mill. ssp.obscurum (Čelak.) Holub
Syn. Helianthemum chamaecistus Mill.; Helianthemum. chamaecistus Mill. ssp. hirsutum (Vollm.) Weim; Helianthemum ovatum (Viv.) Dunal (ssp. obscurum)

NO: Vanleg solrose
SE: Solvända
DK: Filtet Soløje (ssp. nummularium); Bakke-Soløje (ssp. obscurum)
FI: Päivännouto
DE: Gewöhnliches Sonnenröschen (ssp. nummularium); Ovalblättriges Sonnenröschen (ssp. obscurum)
EN: Common Rock-rose

This is a creeping small dwarf shrub of dry meadows, native to Europe and found in elevations from sea level to mountain ranges. The vernacular names reflect the plant's ability to track the sun's position throughout the day.

There are a number of recognised races commonly treated as taxa at the subspecies level. The material collected here corresponds to the ssp. obscurum and has leaves that are green on the underside. Plants collected in the Durmitor National Park of Montenegro, at around 1200 m a.s.l., 20 June 2014.

Attached Image: HELI_NUM_G1406200689_VIS.jpg
Image reference: HELI_NUM_G1406200689_VIS.jpg
Visible light: Nikon Df, Voigtländer APO-Lanthar 125 mm f/2.5 lens, daylight.

Attached Image: HELI_NUM_I1406201645_UV.jpg
Image reference: HELI_NUM_I1406201645_UV.jpg
Ultraviolet light: Nikon D3200 (modified), Coastal Optics 60 mm f/4 APO lens, internal Baader U2"(Venus) filter, SB-140 flash.

The ultraviolet signature shows highly reflective corolla and large basal UV-dark patches.

[Published 1 July 2014]

#2 Andrea B.

    Desert Dancer

  • Owner-Administrator
  • 9,115 posts
  • Location: UVP Western Division, Santa Fe, New Mexico

Posted 01 July 2014 - 14:11

Sometimes one of UVP's flower fotos will just grab one's attention for whatever reasons. Such is the case here. I really like this one. Those little UV-dark pollen grains scattered across the petals are interesting. The foto composition is nice too.

This Helianthemum is somewhat Potentilla like in its UV signature.
Andrea G. Blum
Often found hanging out with flowers & bees.

#3 nfoto

    Former Fierce Bear of the North

  • Owner-Administrator
  • 3,256 posts
  • Location: Sørumsand, Norway

Posted 02 July 2014 - 08:01

As it was blowing hard on this open mountain slope at high altitude, these flowers were not amongst the easiest to photograph in the field. Using the Liveview functionality of my D3200 camera, I observed similar UV signatures on another Helianthemum species nearby, but a violent downpour thwarted all plans of capturing it on camera. This plant had much smaller flowers and probably was H. oelandicum. Before the onset of inclement weather, I did a few other flowers in UV though, and these (Myosotis alpestris, Ornithogalum sp., and Senecio vernalis) will be published subsequently.