Kunihiko Okano was born in Japan on November 19, 1953.  Like many amateur astronomers, his interest in astronomy began early in life.  His first telescope was a 9cm Newtonian that his parents got for him in a department store when he was 10 years old.  The mount was not very satisfactory, so Okanso-san eventually made his own equatorial mount from the front forks and bearings of a bicycle's steering column. He later upgraded to an 11cm telescope and added motors to the bicycle mount so he could drive the scope in both RA and DEC.  His first "astrophoto" was actually taken inside a GOTO planetarium!  Later on, at age 17, using the same 11cm scope and bicycle mount, Okana-san won an award for his photo of M42 published in Tenmon Guide (one of the leading astronomy magazines in Japan).

Okano-san would take a break from astronomy when he went off to University,  He received a BS degree in aero/astronautic engineering (propulsion) and a Ph.D. in nuclear engineering from the University of Tokyo.  He spent 1982 - 1983 at Princeton University's Plasma Physics Laboratory and more than 10 years at Toshiba Research & Development Center.  He is currently an invited Professor of Fusion Energy at Tokyo University.  But in 1986, his interest in astronomy and astrophotography was renewed with the re-appearance of Haley's Comet.

"I was surprised by 2415 film's red sensitivity.  My first idea was to use a red filter with 2415 film to take astrophotos from Tokyo.  But this required very long exposure times, 1 to 2 hours through a deep red filter, so it was very helpful when the ST-4 was introduced.  I reinforced the draw tube and made the guide scope more rigid.  After that I made the first successful 1 hour long guided exposure in Japan with a Takahashi 100 mount and 8" Newtonian scope." 

Okano-san also used the ST-4 for imaging, but soon graduated to an ST-5, ST-6, ST-7.  In 1995 - 1996, using a non-E, ABG version of the original ST-7 and C5 telescope he experimented with color imaging.  The lack of desired sensitivity drove him to seek a better way to combine RGB data to improve the results. Noting that one could change the content of the L channel in Photoshop without deteriorating the RGB data, he wondered if this was useful in processing, why not take a separate L image to improve resolution and take advantage of the increased sensitivity of an unfiltered image?  In this quest he invented the LRGB color combination process used by most imagers today (concurrently Robert Dalby of the UK came up with LCMY).

Okano-san also observed that while digital imaging was more sensitive and more linear than emulsion, there was a unique quality to emulsion that effectively compressed the dynamic range of an image in a very natural and pleasing way.

"During development of film there is a lot of non-linear development - this is why film is very beautiful.  The idea was how to reproduce this using digital techniques."

Okano-san studied the chemistry process of 2415 film development and eventually wrote an algorithm that simulates what happens during the development of film.  In DDP the original image is divided by a defocused image plus an offset to produce a similar result that one sees during film development, hence the name "Digital Development Processing, or DDP:

"I define the pixel level in the original image as x and that in its unsharpened image as y. We consider a conversion of image data by z=kx/(y+a), where k and a are scalar parameters. If a pixel level x is much lower than a, this conversion results in no change in the gamma curve of the image. If x is much larger than a, this conversion reduces the gradient of the gamma curve. Then, the gamma curve is converted in a hyperbolic form. The turnover point is x=a. At the same time, the edge enhancement effect will appear only in the low gradient regime. When the parameter a is chosen very carefully, this process results in an analogous effect to the chemical process of film."

It should be noted that this is different from simple unsharp masking which subtracts a defocused image from an original image.  Both LRGB and DDP have become common tools used by the vast majority of imagers world over to improve the beauty of their digital images.  To read about the theory and math behind LRGB, DDP and DDP Color processing (used by SBIG in CCDOPS for single-shot color conversion) please see Okano-san's write-ups at the following pages:

DDP basic theory   *   Color emphasis by DDP   *   LRGB quad color composit   *   How to carry out the DDP with Hidden Image

In 1997, Okano-san partnered with Kawasaki-san to start the CCD Astronomy Network in Japan.  There was little information in Japan about imaging techniques and most of the available articles were in English.  The Japanese amateur needed a way to find and exchange information about CCD imaging so the CAN conferences were initiated and have been held every year since in either Kyoto or Tokyo.  For the past 10 years Okano-san has written articles for Tenmon Guide about CCD imaging.  Most of his images have been published in Tenmon Guide, Sky Watcher, Hoshi Navi and Gekkan-Tenmon magazines.  He has twice won the Grand Prix award for his images in Sky Watcher.  In addition, Okano-san has authored two books in Japanese on CCD imaging:  "Imaging Techniques for CCD Cameras," and "Digital Eye."  As of this writing, Okano-san uses an ST-7 and C8 for his mobile system, and his permanent set-up is an ST-8 with AO-7 on a 12" f/5 Newtonian in a Dome near Tokyo.  Okano-san is noted for getting the most from modest equipment particularly from light polluted Tokyo.  His mobile system for years was an ST-7 and C5 telescope.

SBIG is proud to present our Award for Excellence in Astronomical Imaging to Okano-san and honored to welcome him to our Hall of Fame.

A few of his images are seen below.  To see more of Okano-san's work, please visit his web site at http://www.asahi-net.or.jp/~RT6K-OKN/
 

 
 
 
 
 
Okano-san's ST-8XME and AO-7 attached to the 12" f/5 Newtonian
in his 2.5 meter dome atop his home in Tokyo
A custom 1.7X extender / corrector lens he designed to match
the backfocus requirements of the AO-7

 

Thanks and Congratulations to Okano-san!

Revised: February 05, 2008 09:01:26 AM.
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