Saturday 31 August 2013

Oxalis tetraphylla (Four-leaved Pink Sorrel) flowers [Vis UV IR]

Oxalis tetraphylla (Four-leaved Pink Sorrel) photographed in visible light (top), ultraviolet light (middle), and infrared light (bottom)

Oxalis tetraphylla (Four-leaved Pink Sorrel) photographed in visible light (top), ultraviolet light (middle), and infrared light (bottom).

In visible light the plant has pink flowers with a green centre. The flowers are quite strongly veined, with the veins leading in towards the centre of the flower. The leaves appear green with a darker, red-green coloured area at the base of each leaf.

In ultraviolet light the centres of the flowers are quite bright, with a much darker centre. The veining present in visible light is also visible in ultraviolet. The leaves are a single tone.

In infrared light the flowers have little variation in tone. The same veining present in visible and ultraviolet light is visible, but only just. The leaves are a single tone, and also appear brighter than they do in visible or UV light.

Gladiolus × hortulanus 'Priscilla' flower [Vis UV IR]

Gladiolus × hortulanus 'Priscilla' flower photographed in visible light (top), ultraviolet (middle), and infrared (bottom)

Gladiolus × hortulanus 'Priscilla' flower photographed in visible light (top), ultraviolet (middle), and infrared (bottom).

In visible light the flower is pale pink with a yellow centre and deeper pink edges.

In ultraviolet light the area near the edge of the petals appears quite dark. The centre of the flower (roughly corresponding to the pale yellow area in visible light) also appears dark.

In infrared light the flower does not have much difference in tone across its petals, appearing very plain.

Buddleja davidii (Butterfly-bush) [Vis UV IR]

Buddleja davidii (Butterfly-bush) flowers photographed in visible light (top), ultraviolet (middle), and infrared (bottom)

Buddleja davidii (Butterfly-bush) flowers photographed in visible light (top), ultraviolet (middle), and infrared (bottom).

In visible light the flowers are purple with an orange centre. There is a slightly lighter area around the edge of the orange centre.

In ultraviolet light the flowers appear as roughly a single tone, with no lighter area around the centre.

In infrared the flowers also appear as roughly a single tone, with no lighter area around the centre.

Achillea ptarmica 'The pearl' [Vis UV IR]

Comparison of Achillea ptarmica 'The pearl' flowers photographed in visible light (top), ultraviolet (middle), and infrared (bottom)

Comparison of Achillea ptarmica 'The pearl' flowers photographed in visible light (top), ultraviolet (middle), and infrared (bottom).

In visible light the flowers appear white with a pale yellow centre.

In ultraviolet light the flowers appear darker. The flowers were photographed when still covered with morning dew, the small water drops very noticeable in UV.

In infrared the flowers appear much the same as they do in visible light in terms of tone.

Saturday 24 August 2013

Montbretia (Crocosmia cv.) [Vis UV IR]

A comparison of how Montbretia flowers appear in visible light (top), ultraviolet light (middle), and infrared light (bottom).

In visible light the flowers appear red with a yellow throat.

In ultraviolet the throat of the flower is much darker. These UV markings are often referred to as 'Nectar guides', as they can be seen by bees and other insects, and help them find the flower's nectar.

In Infrared light the foliage in the background, the stem of the flower spike, and the seed pods on the spike all appear much brighter (than in visible light), having roughly the same reflectance as the flowers.

Water mint (Mentha aquatica) [Vis UV IR]

Mentha aquatica (Water mint) photographed in visible light (left), ultraviolet light (centre), and infrared (right).

In visible light the plant has pale pink flowers with darkish green leaves.

In ultraviolet light the flowers appear much darker.

In infrared light the leaves appear much brighter, exhibiting roughly the same level of reflectance as the flowers.

Silver Ragwort (Jacobaea maritima) [Vis UV IR]

Comparison of Jacobaea maritima (Silver Ragwort) flowers photographed with visible light (top), ultraviolet light (middle), and infrared light (bottom).

In visible light the flowers appear bright yellow, with the centres being slightly darker than the petals.

In ultraviolet light the centres appear quite dark, helping guide bees and other insects that can see in the ultraviolet spectrum to the area of the flower where the nectar and pollen are located.

In infrared light the petals and centres of the flowers have roughly the same reflectance.

Thursday 15 August 2013

Golden Mock Orange (Philadelphus coronarius 'Aureus') [Vis UV IR]

Comparison of Philadelphus coronarius 'Aureus' (Golden Mock Orange) in visible light (top), ultraviolet light (middle), and infrared light (bottom).

In visible light the plant has white flowers and yellow leaves.

In ultraviolet light the area around the base of each petal appear quite dark.

In infrared there is not much of a difference (in terms of tonality) in how the flowers and leaves appear compared to their appearance in visible light.