Confused about formats

[Ron Evans]

Originally Posted by David Heath

Ron - I think you know, but it's worth emphasising that what you link to is (with greater than 50% green photosites) a single sensor design - not 3 chip as the NX5 uses. I believe the >50% green arrangement is most found on relatively low cost camers with small sensors - compared to Bayer, it trades colour fidelity for sensitivity.

Sorry for the late reply but I have been away skiing for a week. Yes David, as I did mention the reference was for the single chip cameras mainly to show the diagonal sensor arrangement . Still have not found the reference for the 3 chip cameras but I am sure they interpolate a 1920x1080 image for each color, The interpolation of course may not truly be as good as a true 1920x1080 sensor but has other advantages in sensor size for sensitivity etc too.

Ron Evans

[Ray Turcotte]

Here are some references to Sony Chip design straight from the chip designers

index:

Sony Global - Technology - View by product


Sony Global - Technology - CMOS Sensor "Exmor"


Sony Global - Technology - "Exmor R"


Sony Global - Technology - ClearVid CMOS Sensor



Also Sony announced a new chip coning out this spring here:

Sony Global - News Releases - Sony Develops Next-generation Back-Illuminated CMOS Image Sensor to Embody the Continuous Evolution of the Camera

and

Sony Global - News Releases - Sony Develops New ....

[Ray Turcotte]

Since this thread is titled “confused about formats”, I have a follow on question about Shutter speeds with Sony cameras.

A “general rule” when shooting video is that the shutter speed should be 2x the frame rate or in film camera days, the shutter angle set to 180 degrees.

Yet on my Ax2000, if the shutter speed is set to auto, it will default to the following values:

Frame rate Shutter speed
24p 1/48
30p 1/30
60i 1/60


Does this imply 30p has a 360 shutter angle,

and 60i is comprised of 2 1/60 ½ frames (that are offset) that are re-combined into a 30fps playback stream? (Ie interlaced combing)

Thanks

[Ron Evans]

60i is recorded as fields, half vertical resolution, 59.94 fields a sec in NTSC, the camera exposure rate which accounts for the smooth motion on a CRT which displays fields. The time code for this is 29.97 frames per sec. How this gets displayed on a progressive display is totally dependent on the deinterlacing electronics. But most NTSC progressive displays will be at 60P or greater. Timecode will still be 29.97fps. It is worth noting that whatever the exposure rate the display governs what one sees and for a simple NTSC panel it will be at 60P. 24P will have 3:2 pulldown and 30P will get doubled to create a 60P playback image.
72hz, 120hz and 240hz panels have the option of displaying 24p in a more native fashion. ( like a multi blade film projector).

Ron Evans