Crop mode questions at DVinfo.net

Fergus Anderson · March 2nd, 2010, 10:28 AM

Hi guys

I was just wondering if the moire and/aliasing artifacts are also present on the crop mode? Should these be eliminated if crop mode does not have to use line skipping etc?

Also if Canon were to introduce a 1080p crop mode - what would the magnification be? (if 480p is 7x)

Fei Meng · March 2nd, 2010, 11:48 AM

I believe that the crop mode still does line-skipping or pixel-binning. That's what should be happening, according to math. The crop mode is 7x magnification, which means that the cropped image area is 1/7th the size of the whole image. 1920*1080=2073600, and 640*480=307200. Do you see?

The resolution of the sensor is 4724*3832. If you don't do line-skipping or pixel-binning, then the center 640*480 pixels would be a tiny fraction of the overall image.

Fergus Anderson · March 4th, 2010, 08:40 AM

Thanks for that - I see!
So 4724*3832 = 18102368
1920*1080=2073600
18102368/2073600= 8.7

So a 1080p crop mode without pixel binning/line skipping would be a magnification of 8.7 - shame!

Perhaps a 3k crop would be better?!! (3.4 magnification)
How does the red camera do sensor crop - do they bin pixels too?

Fei Meng · March 4th, 2010, 05:41 PM

RED doesn't do pixel-binning of any sort, AFAIK.

March 2nd, 2010, 10:28 AM	#1
Fergus Anderson Major Player Join Date: Nov 2006 Location: London, UK Posts: 321	Crop mode questions Hi guys I was just wondering if the moire and/aliasing artifacts are also present on the crop mode? Should these be eliminated if crop mode does not have to use line skipping etc? Also if Canon were to introduce a 1080p crop mode - what would the magnification be? (if 480p is 7x)

March 2nd, 2010, 11:48 AM	#2
Fei Meng Regular Crew Join Date: Mar 2009 Location: Austin, TX Posts: 78	I believe that the crop mode still does line-skipping or pixel-binning. That's what should be happening, according to math. The crop mode is 7x magnification, which means that the cropped image area is 1/7th the size of the whole image. 19201080=2073600, and 640480=307200. Do you see? The resolution of the sensor is 47243832. If you don't do line-skipping or pixel-binning, then the center 640480 pixels would be a tiny fraction of the overall image. __________________ Current cameras: Canon EOS Digital Rebel T2i (coming soon) \| Panasonic LUMIX DMC-GH1 \| Sony HDR-SR11 (infrared modded)

March 4th, 2010, 05:41 PM	#4
Fei Meng Regular Crew Join Date: Mar 2009 Location: Austin, TX Posts: 78	RED doesn't do pixel-binning of any sort, AFAIK. __________________ Current cameras: Canon EOS Digital Rebel T2i (coming soon) \| Panasonic LUMIX DMC-GH1 \| Sony HDR-SR11 (infrared modded)

March 4th, 2010, 08:40 AM	#3
Fergus Anderson Major Player Join Date: Nov 2006 Location: London, UK Posts: 321	Thanks for that - I see! So 47243832 = 18102368 19201080=2073600 18102368/2073600= 8.7 So a 1080p crop mode without pixel binning/line skipping would be a magnification of 8.7 - shame! Perhaps a 3k crop would be better?!! (3.4 magnification) How does the red camera do sensor crop - do they bin pixels too?