Monday, February 12, 2018

ZUFAR 4/350mm quartz fluorite catadioptric lens II

Today more about that Quartz Fluorite catadioptric ZUFAR-2CA f4/350mm anastigmat lens which took me over 10 years to find. It had been developed for the Soviet MARS 2 to 5 missions to planet Mars, was made of synthetic Quartz and Calcium Fluorite (CaF2) crystals to be able to work in UV and also visible light, thus allowing to take images 300-700nm without focus shift.


So today a few first test shots using this very special lens, due to lack of the mount which need to be designed and made, just some freelensing shots. "Freelensing" means holding the lens in front of the camera without any mount in between the two (!).

Here some visible light shots, showing how this lens performs. This first one is about 150 meters away:




and the following one about 15 meters:



The lack of chromatic aberration gets easily visible on that golden ball as well as on these shiny stainless steel exhaust pipes.

Now on to reflected UV images (300-400nm), here right out of camera:



and here with whitebalancing applied:


Being able to handheld a f4 350mm lens and shooting in reflected UV (300-400nm) is rather astonishing, a proof how much UV this lens is able to transmit. More about this lens will certainly follow here...

I have written about this lens before HERE


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

Monday, February 5, 2018

ZUFAR 4/350mm quartz fluorite catadioptric lens

Today about a Quartz Fluorite catadioptric ZUFAR-2CA f4/350mm anastigmat lens which took me over 10 years to locate. It had been developed for the Soviet MARS 2 to 5 missions to planet Mars.



It was made of synthetic Quartz and Calcium Fluorite (CaF2) crystals to be able to work in UV and also visible light, 300-700nm without focus shift, so actually is an apochromatic (APO) f4/350mm catadioptric lens. The whole useful wavelength range is 230-700nm. Lens transmission is 60-65% and the lens resolution is 57 lpm in its center, 47 lpm in corners. Viewing angle is approx. 6 degrees. There has also been made a ZUFAR-1 lens with f4 / 500mm and 4 degrees viewing angle.

ZUFAR lenses have been designed in the 70s under the lead of Institute head and chief designer Prof. Volosov together with N. Khmelnikova, I. Driatskaya, K. Mikhailova at GOI, the russian state lens design institute in St. Petersburg / Leningrad. Details were published by Prof Volosov in 1974.

(Made for my use by my dear friend Marco Cavina)

Data of this lens, as well as its normal (= non catadioptric) quartz fluorite sister lenses
with shorter focal lengths may be found on my macrolenses database site HERE


This lens was made to be used on a very elaborate camera system which could take multispectral images on film, develop that and scan it and send the scanned data back to Earth in selectable resolutions (up to 2000x2000 pix, which took over one hour to transmit).


NASA also wrote about this lens (quote):

Zufar objectives were used on the television cameras carried by the Mars-2, 3, 4, and 5 spacecraft. The compact catadioptric quartz-fluorite anastigmat was developed as a result of research on the possible optical arrangements of lens and mirror-lens systems meeting the rigid criteria for spaceborne operation. The system is characterized by precise correction of all aberrations over a broad spectral range, about 300-700 nm. The spectral transmission is about 60% over this range. The Zufar-2CA version of the objective has a geometric aperture ratio of 1:4 and a focal length of 350 mm. The image format is 24 x 24 mm. The housing is 164 mm long and 130 mm in diameter, and the mass of the objective is 1500 g.

Here one of the published images from Mars taken on Mars-5 mission:




The lens will be given a suitable adaption to fit my digital multispectral cameras and I will certainly take multispectral photos with it as soon as possible and report about here later on.

There is more about this lens HERE including some first images taken with it.


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

Monday, January 15, 2018

American Natural History Museum exhibit "Our Senses"

The exhibition project management of the American Natural History Museum had asked me to participate with some of my works for their forthcoming 2017-2019 exhibit "Our Senses", which has already opened its doors to the public November 20, 2017 and it will last until Sunday, January 6, 2019

(quote AMNH) Every day, we perceive the world around us through our senses - including sight, smell, hearing, touch, balance, and taste. But as it turns out, for humans “reality” isn’t ever exactly what it seems. In this highly experiential exhibition, explore 11 funhouse-like spaces that dare you to trust your senses - then show you how what we perceive is not simply a window into the world around us but a product ofour brains. Plus, discover why we have senses and what’s unique about human perception during an interactive session hosted by a live presenter. (unquote)


 (c) AMNH

My contribution will be some of my multispectral Rudbeckia fulgida flower images, demonstrating the difference between our human vision and the vision of a butterfly and a honey bee (simulated).

(c) AMNH, Dr Klaus Schmitt


It also includes some images which help to understand what monach butterflies may see, as it allows visitors by using a push button to switch from their human vision into butterfly vision on 3D modeled flowers.
(c) AMNH

I'm certain this exhibit is visually stunning, as well as highly educative since it is interactive and suited for interested individuals as well as families, their kids and school classes.

(C) AMNH

Go have a look, it will be well worth it!

If you like to have a look into the Educator's Guide, HERE is the link to it!

For further reading here is an interesting, quite more detailed article about this exhibit and here Scientific American has written about it.


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

Sunday, January 14, 2018

Winter Jasmine - Jasminum nudiflorum in reflected ultraviolet photography and simulated butterfly and bee vision V

Today shots of a decorative winter flower Winter Jasmine - Jasminum nudiflorum in reflected ultraviolet photography using my "work horse" UV filter, the Baader-U filter as well as in simulated bee and butterfly vision using my XBV filters. All shots were done at f11. Lens was a UV-Nikkor 105mm quartz fluorite lens. Light source was a modified Xenon flash. Different camera system used with up to 80Mp resolution.

[click on image to see a larger one]

Human vision:
 

Reflected UV:
  

Simulated butterfly vision:
  

Simulated bee vision:
  

Quadriptych of human vision, UV, and simulated butterfly and bee vision (left to right, top to bottom):
 


This attractive winter flower shows its very specific "bullseye" UV pattern. Its center is UV dark, but its petals are strongly UV reflective around 365nm, ie. UV bright, both invisible to us humans and all that gets nicely visible also in simulated bee and butterfly vision also with this higher resolution camera system.

I have previously written about this flower HERE

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

Saturday, January 13, 2018

Winter Jasmine - Jasminum nudiflorum in reflected ultraviolet photography and simulated butterfly and bee vision IV

Today shots of a decorative winter flower Winter Jasmine - Jasminum nudiflorum in reflected ultraviolet photography using my "work horse" UV filter, the Baader-U filter as well as in simulated bee and butterfly vision using my XBV filters. All shots were done at f11. Lens was a UV-Nikkor 105mm quartz fluorite lens. Light source was a modified Xenon flash.

[click on image to see a larger one]

Human vision:
 

Reflected UV:
  

Simulated butterfly vision:
  

Simulated bee vision:
  

Quadriptych of human vision, UV, and simulated butterfly and bee vision (left to right, top to bottom):
 


This attractive winter flower shows its very specific "bullseye" UV pattern. Its center is UV dark, but its petals are strongly UV reflective around 365nm, ie. UV bright, both invisible to us humans and all that gets nicely visible also in simulated bee and butterfly vision.

I have previously written about this flower HERE

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

Thursday, September 14, 2017

How to simulate what birds may see: simulated bird vision

Birds (many of them) have the ability to see UV (ultraviolet) light, which we humans cannot see.

The following graphic illustrates that by comparing our (rather limited) human spectral range to the larger one birds have, including UV (ultraviolet), based on them being tetrachromats (they see 4 colors: UV, Blue, Green, Red approx. 300-700nm), whereas we humans are trichromats (we only see 3 colors: Blue, Green, Red, approx. 400-700nm).

Be reminded: The pink-magenta UV "color" shown here has been chosen to make it better visible for us humans, it is a "false color", as per definition UV light (approx. 300-400nm) has no color!

A flower with an underlying UV pattern, such as a Rudbeckia fulgida then looks like this in human vision (left) and simulated bird vision (right):



So how may then birds look like, seen through birds eyes? Possible like this (it is simulated bird vision on the right):


I have used this to make visible in still photography and videography what birds may seen of a bird protecting device, the FireFly bird diverter, which may bee seen HERE

But how has this been done? Well, in principle using photographic technology, but with a twist:

Normal photography uses (as per today) a digital camera with a built in sensor, a greenish/blue filter stack in front of that sensor, which limits and adjusts its much broader sensitivity range (UV to IR, approx. 300-1000nm) to the human vision range (approx. 400-700nm), using a suitable standard taking lens, made of optical glass. And of course a suitable lightsource is needed, sun being the best, as it provides a useful amount of UV in its light spectrum

Now this type of multispectral photography needs a modified camera (internal filter stack removed and replaced by an UV and visible light transmitting, clear fused silica window), a suitable UV transmitting special quartz-fluorite lens (the UV-Nikkor 105mm being one of only a few ever made ones), and special filters which allow to record UV images (such as the Baader-U UV transmitting, but visible light blocking filter), as well as filters to record the normal visible light (Blue, Green, Red).

The resulting UV and VIS (Blue, Green, Red) images are then suitably combined into one "multispectral image", in our case here the "simulated bird vison" image. [That term "suitably" describes a rather complex mapping process which I will not describe in detail here. NASA uses similar processes to generate their amazing images from their Hubble space telescope or their Earth observation satellites]

[all graphics shown here are (C) Hammarprodukter AB and Dr Klaus Schmitt, used with permission]

If you are interested into that type of photography, HERE on my site is a lot about it, including my "cook book" style tutorial how to do it.

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

Wednesday, September 13, 2017

Bird Protection using FireFly Bird Diverter

Today about birds and how to protect them against collision with power lines. Each year millions of birds die, especially when migrating in spring and autumn. The patented FireFly device was invented and manufactured by Hammarprodukter AB to protect them.

The following videos were shot at Kübassaare / Saaremaa Island, Estonia in 2017, as a proof that a carefully designed bird diverting device, such as the patented FireFly (and BirdMark) made by Hammarprodukter AB of Sweden, works efficiently to divert birds and make them change their flight path, hence protecting their lifes.

[click images to see larger ones]

Power line at Kübassaare / Saaremaa island / Estonia:
 
(C) Hammarprodukter AB

The following video was shot in June and August 2017 in normal human vision, in simulated bird vision at daylight, but also at dusk / night to show the afterglow effect this FireFly device has, aside from its intense flickering when rotating,  which can be seen up to 350-400 meters, which is the visible distance covered in this video. Several overflights were recorded, where birds actively changed their normal flight path.

[best to watch in HD full screen]




Here now a screen shot showing how efficient FireFly was able to divert the flight path of the birds.

Simulated bird vision still image from video with diverted flight path:
 

Birds (many of them) have the ability to see UV (ultraviolet) light, which we humans cannot see! This grahic here makes this visible by comparing our human spectral range to the larges one birds have, based on them being tetrachromats (they see 4 colors), whereas we humans are trichromats (we see 3 colors).

Be reminded: The pink-magenta UV "color" seen here has been chosen to make it better visible for us humans, it is a "false color", as per definition UV light has no color!


So how may then birds look like, seen through birds eyes? Possible like this (it is simulated bird vision on the right):


The Hammarprodukter FireFly also makes use of this knowledge, to scare birds away from high voltage powerlines, which may harm birds!

HERE a link to the manufacturer product site Hammarprodukter.se

And HERE more about human vision vs bird vision and how to make that visible. 

[all graphics shown here are (C) Hammarprodukter AB and Dr Klaus Schmitt, used with permission] 

More about that here later, as I took on the task to scientifically assist Hammarprodukter AB.

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