Re: Infrared K20D (anyone)?

[Mark Roberts]

Bob Blakely wrote:
> The filter pattern for Pentax (and most cameras) creates one pixel from four 
> sensors, usually:
> 
> RG
> GB
> 
> After thinking about this for some time, I believe that the following 
> pattern would be better for many who would like to explore photography at 
> wavelengths other than visible. I propose the following pattern (or 
> something similar):
> 
> RG
> UB
> 
> Where "U" is unfiltered - like astronomy cameras.

Kodak beat you to it (announced June, 2007): 
http://www.dpreview.com/news/0706/07061401kodakhighsens.asp



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Re: Infrared K20D (anyone)?

[Bob Blakely]

The filter pattern for Pentax (and most cameras) creates one pixel from four 
sensors, usually:

RG
GB

After thinking about this for some time, I believe that the following 
pattern would be better for many who would like to explore photography at 
wavelengths other than visible. I propose the following pattern (or 
something similar):

RG
UB

Where "U" is unfiltered - like astronomy camers.

Internal camera software/firmware processing would select only the RGB for 
normal photography and various combinations for "pseudo" filtered B&W 
photography - including IR & UV!

The internal software/firmware would produce a "RAW" format with all four 
channels and provided external software would select the desired channel mix 
for software filtering.

The camera's LCD should produce the desired output real time as selected so 
that the IR & UV folks can properly focus for these wavelengths. Note: for a 
sharp photo, one would still need IR or UV bandpass filters on their lenses 
or telescopes, though interesting effects such as normal RGB (in focus) and 
UV (slightly out of focus due to different wavelength) with an IR bandstop 
filter would give a reasonable facsimile of a parrot's eye view of foliage - 
as much as we could show it for our eyes.

A lot of experimentation could ensue...

What would we loose (aside from the added firmware/software/sensor filter 
cost? Maybe 1/3 stop. I could live with that.

Regards
Bob...
---
"I don't mind if you don't like my manners.
I don't like them myself. They're pretty bad.
I grieve over them long winter evenings."
  -- Philip Marlowe (Humphrey Bogart)


- Original Message - 
From: "Roman Melihhov" <[EMAIL PROTECTED]>


> Is it possible to use Pentax K20D for IR photography without replacement
> of the sensor filter glass.
>
> Thank you for your info.


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Re: Infrared K20D (anyone)?

[timber]

> I've seen lots of Nikons and Canon dslrs on eBay that have been modified
> for just IR only.   Rarely see Pentax dslrs.
>
> Jim A.

The same applies for the unmodified cameras :) Tons of ***ons and just a
few Pentax.

Probably because Pentax users love their cameras and they keep them
instead of getting rid of it :)

.t


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Re: Infrared K20D (anyone)?

[Ralf R. Radermacher]

<[EMAIL PROTECTED]> wrote:

> I've seen lots of Nikons and Canon dslrs on eBay that have been modified
> for just IR only.   Rarely see Pentax dslrs.

The *IstDS used to have quite decent IR performance without any
modification. I've been able to take IR photos at wavelengths far
exceeding the capabilities of films like SFX 200 or Konica IR750.

WARNING: The link below leads to a Russian website that has been accused
of causing problems with sh*tty operating systems. Go there under Mac
OS, Linux, or at your own risk. ;-)

http://www.photosight.ru/photos/1544630/?from_member

Ralf

-- 
Ralf R. Radermacher  -  DL9KCG  -  Köln/Cologne, Germany
private homepage: http://www.fotoralf.de
manual cameras and photo galleries - updated Jan. 10, 2005
Contarex - Kiev 60 - Horizon 202 - P6 mount lenses

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Re: Infrared K20D (anyone)?

[japilado]

I've seen lots of Nikons and Canon dslrs on eBay that have been modified
for just IR only.   Rarely see Pentax dslrs.

Jim A.



> Is it possible to use Pentax K20D for IR photography without replacement
> of the sensor filter glass.
>
> Thank you for your info.
>
>
> --
> K20D, DA10-17mm, DA16-45mm, FA50mm_f1.4, DA50-200mm, Dörr DStudio
> strobes roman.blakout.net 
>
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Re: Infrared K20D (anyone)?

[timber]

> Is it possible to use Pentax K20D for IR photography without replacement
> of the sensor filter glass.
>
> Thank you for your info.
>

Possible, with extreme long shutter speeds even at f2.8. It has like -20
EV reduction. And the Live View is useless with IR sensors on.

I think if you want to go IR with Pentax you need K200D or modding your
camera (which I am planning with K10D)

.timber


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Infrared K20D (anyone)?

[Roman Melihhov]

Is it possible to use Pentax K20D for IR photography without replacement 
of the sensor filter glass.

Thank you for your info.


-- 
K20D, DA10-17mm, DA16-45mm, FA50mm_f1.4, DA50-200mm, Dörr DStudio 
strobes roman.blakout.net 

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