[UV, VIS, IR] Lyman Alpha deep UV lenses III

Today tests shots in reflected ultraviolet photography with a NYE OPTICAL Lyman-Alpha I f2.8/200mm UV-VIS-NIR lens. UV filter used was my work horse UV transmission filter, the Baader-U, rear mounted. All shots were done at f2.8 as this lens has no iris. Light source used was daylight at a dull and rainy day.

[click on image to see a larger one]

Roof detail approx. 30ft/10m away:
 

Window detail approx. 30ft/10m away:
 

Absence of CA, easily seen on the stainless steel exhaust tubes approx. 60ft/20m away:
 

Closeup shot of an African Violet, approx. 3ft/1m away, using Nichia UV LED (365nm):
 

This lens has a UV transmission in the 190-400nm range of 85-88% and a resolution of 25lpm at infinity and 60lpm at 300mm distance and covers full format (maker data).The test images certainly confirm its usefulness.

I have written about the Nye Lyman-Alpha lenses previously HERE
 
Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

LDM-1 long distance microscope for reflected UV (ultraviolet) light and African Violet

Today shots of an African Violet flower in reflected ultraviolet photography using a UV filter stack consisting of SCHOTT UG1 + BG40. All shots were done at f11. Lens was a rather rare LDM-1(s) 800mm mirror only lens, the close-up using the AP300 achromatic cloe-up lens, which was once sold with this lens system. Light source used was a 365nm Nichia UV LED light.

[click on image to see a larger one]

LDM-1(s) alone:
 

LDM-1(s) with the AP300 achromatic close-up lens:
 

And now here some comparison images I have shot with my "work horse" UV-Nikkor 105mm plus Baader-U filter.

Overview:
 

Closeup at closest focusing distance:
 

I have written about this LDM-1 lens previously HERE
 
Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

[UV, VIS, IR] Lyman Alpha deep UV lenses II

Oh well, it has been five years, but now I finally infinity-converted these very special lenses...

Back a little in time: When in 2012 I was able to acquire three prototypes of those lenses, made 1992, which came from the estate of the inventor, Richard Nye and his company, Nye Optical of La Mesa CA, I was very excited to find such lenses able to record in deep UV. But they turned out to be a bit tricky to convert and adapt to digital cameras. Now with mirrorless ones, it looked rather promising...

So, these scientific lenses Mr Nye invented and custom made, were for deep UV recording (capable to even work beyond 200nm, especially made to record the 121nm Lyman alpha lines, hence the name). It is a catoptric (reflex) Cassegrain design, which came in f2.8/200mm and f1.1/90mm (and some other) versions for full format cameras, but also for intensifier tubes and video cameras (25mm image circle, like the f1.1/90mm), with focusing from 250mm to infinity and some adjustable 50mm resp.18mm back focal length. And now I have them working on my Panasonic GH4 camera....

[click on image to see a larger one]



Inside the aluminum housing resides an about 25mm (1") thick quartz (ZERODUR most likely) mirror block, front aluminized plus a secondary mirror (most likely made of the same material) held by an adjustable metal "spider" in front of that first one. Quite built like a small 90mm diameter Cassegrain astronomical telescope.

DOF at one (1) meter (3ft) is as thin as a razor blade when using the Lyman Alpha f1.1/90mm lens and that doughnut shaped bokeh etc. makes it fun to use.

Here now a few images in visible light, UV will follow, weather permitting...

The very thin DOF of course generates those doughnut shaped bokeh bubbles, but by chosing a proper i.e. less noisy background it can be "tamed".

I have written about those lenses before HERE


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Common Sunflower - Helianthus annuus in reflected ultraviolet photography and simulated bee vision

Today shots of a flower everybody has already seen, a common Sunflower - Helianthus annuus in reflected ultraviolet photography using my "work horse" UV filter, the Baader-U filter as well as in simulated bee vision using my XBV filter. Lens was my UV-Nikkor 105mm quartz flourite lens. Light source was sunlight. All shots were done at f8.

[click on image to see a larger one]

Human vision:
 

Reflected UV:
 

Simulated bee vision:
 

Triptych of human vision, UV, simulated bee vision (left to right):
 

This flower has a specific and unique UV pattern, its petal tops are brightly UV reflective around 365nm and the rest and its center is UV dark forming an UV bullseye pattern, and all this gets nicely visible, also in simulated bee vision.

I have written about sunflowers before HERE
 
Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos