Well, I Had to Try It Once...

[OlDoinyo]

Of all the crazy things to do with a UV-enabled camera, what could be crazier than shooting from an airplane? So I have thought for a long time...but curiosity has a way of nagging, and today, on the way back to North Carolina from a Colorado/Utah trip, I gave in for a bit. I did not want to waste film on this, so I used the Sony A900. To enable the use of a 1/250 second shutter speed at f/16, I had to resort to sensor gains in the 1600-6400 range--and frankly, the A900's image quality in that territory is not good, but this is after all just a demonstration.

 

From central Missouri all the way to the Tennessee/North Carolina border, the route was underlain by a prominent haze deck punctuated with various patterns of stratocumulus clouds. If you have ever been to the Georgia O'Keeffe Museum in Santa Fe, you will see a couple of small paintings the artist made of clouds such as these seen from an airplane, and I took a number of visible and IRG frames of these clouds in addition to what is below. The sky above cruising altitude (11,500 feet) was blue and clear, and it was early afternoon. Visibility above the haze deck was probably 200 km or better; on the ground it was probably about 20 km. The haze was transparent to the eye, though quite prominent.

 

It was not possible to shoot through the airplane's plastic windows, as they turned out to be virtually opaque to UV. Fortunately, there is a small openable mini-window to the side of the instrument panel, and the camera can be aimed through this with care. At 130 knots, the airstream will definitely blow the dust off your filter--but if you allow the neck strap to get sucked out the opening, the results are loud and disconcerting, and losing anything out the window is quite irrevocable. All frames were taken with the Sony A900 using the Steinheil 50mm lens set at f/16 and with the Baader U2 filter and a shutter speed of 1/250 second. ISO was set at 1600, 3200, or 6400. Workup included varying amounts of contrast-boosting and generous use of Topaz DeNoise to try to counter the noisy camera images. In the two color frames, display intent is BGR.

 

In the UV, the haze deck is almost opaque--in only one of the flat-land frames is any ground detail discernable, and that in a frame that is otherwise the least interesting:

 

 

As I came across the border into North Carolina, the broken cloud deck ended, and the mountains came into view. Yesterday's cold front caused rime icing on trees and dumped a small amount of snow on the higher ridges:

 

 

I save the best result for last--I am almost thinking that it has a smidgen of aesthetic merit.

 

"A Wing and a Prayer:"

 

The white paint on the wing is chock-full of you-know-what; I guess they wanted it to stand up to a bit of sunshine!

 

Notice also that there is no clear view to the horizon even above the haze deck--the view fades into the murk somewhere in the middle distance, creating a very different impression than what would be seen at longer wavelengths. As these were taken in the eastern US, I wonder how much of a role air pollution plays in the UV-scattering of the middle atmosphere. Although one could easily see beyond the horizon, UV photography is more sensitive to such factors.

[colinbm]

Well IR would have looked good........

Perhaps next time you could take a flower with you into the cockpit & show us how much more UV is available for a sunlight UV flower shot at altitude ?

Col

[OlDoinyo]

Aerial IR is another story altogether--and I have done some:

 

https://www.flickr.c...ared&view_all=1

 

Here, in fact, is a synthesized IRG frame from the same flight using a Tiffen #15 filter:

 

 

There is little or no UV inside the cockpit for reasons mentioned above. However, one of my UV photos, "Braving the Gale," was actually taken at higher altitude than these, albeit from a ski lift rather than an airplane. Exposure data tells me that there is indeed a generous amount of UV at such elevations, and in summer there would be tundra wildflowers up there. Perhaps one day I will investigate.

[Andy Perrin]

I've taken infrared at general aviation altitudes (1000 feet, versus 10000 ft and more for a commercial jet). Some may be lower than that even, since we were in a helicopter. Samples below. (All are taken with CoolPix 995, 850nm NEEWER filter, if memory serves... Saturation was upped quite a lot in most of these.)

 

 

[nfoto]

I did a lot of false-colour IR from smaller air crafts many many years ago. It really was providing a helpful insight into the ecosystems I studied at the time. No UV back then, unfortunately. I wonder what we would have come up with?