Re: bdeh bdeh bdeh: that's all folks

-----Original Message-----
>From: John R Pierce <pierce@No-Spam>
>Sent: Mar 31, 2010 3:03 PM
>To: TAC mailing list <tac@No-Spam>
>Subject: Re: [TAC] bdeh bdeh bdeh: that's all folks
>
>Richard Crisp wrote:
>> John
>>
>> those horizontal streaks are from screwheads that are used to retain the filters
>>
>> I had painted them flat black but the paint chipped off of them a little bit.
>>
>> with a smaller sensor there would have been no visible artifact.
>>
>> these big sensors (this is 36.8 x 49mm) really push everything:
>>
>> optics: flat field, aberrations, vignetting, tilt
>>
>> mechanicals: play, tilt
>>
>> computer: processing gigabytes of data etc
>>
>
>wow, thats almost 'medium format'. IIRC, "6x4.5" format is around
>56x42mm actual image size (my medium format is 6x7, about 56x69mm)
>

John, the one shot color version of the sensor, what I was using last year, was developed by Kodak at Hasselblad's request. They use it in the H3DII-39MS

http://www.engadget.com/2007/10/18/hasselblads-39-megapixel-h3dii-39ms-dslr-brings-the-multi-shot/

That is a digital "medium format" camera.

because of the fast lenses from hasselblad and the large size of the sensor and the sharp angle for the chief rays off axis, Kodak did not use microlenses in order to avoid the light admittance angle issue and to avoid color cross talk. Additionally there is a light shield surrounding each pixel to fight color crosstalk. That reduces the fill factor to approximately 55%.

for those reasons the QE is sort of low (around 20-22%)

but if you have enough time to spend on the object it takes nice images. I like the monochrome better than the one shot color I used last year about this time.

http://www.narrowbandimaging.com/m31_lrgb_ap155_pl39K_pl16803_page.htm

http://www.narrowbandimaging.com/m8_m20_ap155_pl39K_page.htm

http://www.narrowbandimaging.com/ic1274_ap180_pl39K_baader_page.htm

http://www.narrowbandimaging.com/proline_39k_color_page.htm

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