Sumix 2/3" 1920x1080 CMOS

Solomon Chase · August 23rd, 2008, 07:04 PM

Quote:

Originally Posted by Daniel Lipats

Well there are two things to keep in mind about the pictures...

First... I'm mixing daylight (~5600k) and tungsten (3200k) lighting. So colors are going to look a little funny. Especially when mixed in the (white) sails.

Second... The color filter in the camera is incorrect. It blocks some colors more than others and leaves a tinted and desaturated image.

I have been referred to the correct filter, but I'm going to wait for Sumix to provide the official hardware fix.

Were you referred to a third-party color filter? and is the fix provided by Sumix going to be a new filter or a color matrix (firmware) update as well?

Daniel Lipats · August 23rd, 2008, 07:36 PM

The IRC-30 filter here:
IR cut-off filter

The filter I'm using right now cuts out red light, and when compensating with white balance it increases the noise by boosting the signal. Furthermore, the filter cuts out an additional 50% of all visible light. The camera is not performing as well as it should be.

I'm not sure which filter I have. My results are similar to:
http://www.dreamstonestudios.com/per...industrial.JPG

Here is a chart with the IRC-21 (cheaper filter)
http://www.dreamstonestudios.com/per...umix/IRC21.JPG

Finally, the IRC-30 (recommended filter)
http://www.dreamstonestudios.com/per...umix/IRC30.JPG

Images were provided by Sumix

Solomon Chase · August 23rd, 2008, 08:48 PM

That first color chart is TERRIBLE. Hardly any color information.

The IRC-30 gets you about about 70% there. If you add color matrix calibration, you can get a lot closer, but you can still see that the colors aren't pure.

See attached image.

Eric Wu · August 24th, 2008, 01:36 AM

Hello Daniel,

Can you confirm that the camera can be set to run 1920x1080, 24fps, 1/48 shutter speed (exposure time = 20.833ms) and 12-bit output, at the maximum pixel rate (74.76 MHz)?

I think this is the most common mode if we are using this camera for digital cinema works. To minimize the rolling shutter effect it's crucial to run it at the maximum pixel rate.

Thanks!

Daniel Lipats · August 24th, 2008, 05:19 PM

Eric,

I just tried setting the camera to that configuration, seems to work fine. The screenshot below will help answer your question. As far as I know, yes it is capable of running at the settings you mentioned.

Eric Wu · August 25th, 2008, 12:04 AM

That's great news, Daniel.

I noticed the exposure showed 0.769128ms, which is about 1/1300 shutter speed. I suppose it's the minimum value, isn't it? Otherwise it wouldn't make sense.

I'm planning to order one of the camera and write my own software. What I have in mind is recording uncompressed 12-bit RAW, real-time preview while recording, and a touch-screen UI like the SiliconDVR's.

Thank you for sharing the informations and doing the tests.

Daniel Lipats · August 25th, 2008, 12:13 AM

Eric,

I'm not sure how to interpret the exposure value. That is in fact the maximum setting. I did not try to override with a manual input but I don't think it will work. The maximum exposure value depends on the set frequency, at 10 MHZ it peaks at only 4.98 ms or so.

I'm going to try and order the IRC-30 filter tomorrow and figure out a way to mount it. The filter should make a considerable improvement to the picture quality.

Eric Wu · August 25th, 2008, 03:01 AM

I'm no expert but I think an optical low-pass filter is needed to eliminate aliasing. So maybe it's these OLPFs incorporated with IR cut-off function that you'll need:

Optical low-pass filter

Biel Bestue · August 25th, 2008, 03:34 PM

is there a need of low pass filter? how is aliasing showing? any clear example? oh, and Daniel, can you post a screenshot of every segment of that "settings" window you posted above?

Eric Wu · August 25th, 2008, 08:00 PM

Aliasing and Moire patterns
Moiré pattern - Wikipedia, the free encyclopedia

I think most hi-end digital cameras have OLPF. It's likely the original Sumix filter is one, too.

Biel Bestue · August 26th, 2008, 03:04 AM

yeah i know that, that's why i suggested the use of that "new" patern in the bayer filter, but i guess that is not up to sumix but up to the maker of their imagers, that patern could get the same information from half the numbers of photosites, so we would be getting double amount of information, so a pixel binning thechnique should do to combat aliassing, but i gues sumix don't print the bayern patern in the imagers of their cameras

Daniel Lipats · September 4th, 2008, 06:20 PM

Quick update, I ordered the IRC30 filter earlier this week and it will be coming in the mail tomorrow.

I will try to find time this weekend to shoot a few more tests.

Daniel Lipats · September 6th, 2008, 04:44 PM

Here are the results from earlier today, shot with the new filter. Natural light only.

http://dreamstonestudios.com/persona...es/IRC30/1.jpg
http://dreamstonestudios.com/persona...es/IRC30/2.jpg

Gottfried Hofmann · September 7th, 2008, 11:22 AM

Daniel, do you have an idea where the pattern on the corner of the clock comes from?

Eric Wu · September 8th, 2008, 12:03 AM

Hi Daniel,

These pictures are gorgeous! To my eyes the resolution and dynamic range are very good. Even better if you can upload some footages.

The colors are not very different from your last pictures, though. Which is not a bad thing IMO. Raw data directly from the sensor are not optimized for human vision. Those Sony, Panasonic video cameras do a lot of processing like color matrix, white balancing, curves, before outputting the image. But those can all be done in post. recording raw data keeps the maximum flexibility for post processing.

There seem to be debayering artifacts. I'm not sure if that's what Gottfried Hofmann refers to but I think it can be easily fixed by choosing a more sophisticated debayer algorithm.

August 23rd, 2008, 08:48 PM	#468
Solomon Chase Regular Crew Join Date: Jan 2006 Location: Woodstock, Georgia Posts: 154	That first color chart is TERRIBLE. Hardly any color information. The IRC-30 gets you about about 70% there. If you add color matrix calibration, you can get a lot closer, but you can still see that the colors aren't pure. See attached image. Attached Thumbnails __________________ BATTERYFIRE - Visual Effects / Film / Design http://www.batteryfire.com

August 24th, 2008, 05:19 PM	#470
Daniel Lipats Major Player Join Date: Feb 2006 Posts: 260	Eric, I just tried setting the camera to that configuration, seems to work fine. The screenshot below will help answer your question. As far as I know, yes it is capable of running at the settings you mentioned. Attached Thumbnails

August 25th, 2008, 03:34 PM	#474
Biel Bestue Regular Crew Join Date: Jul 2005 Posts: 96	is there a need of low pass filter? how is aliasing showing? any clear example? oh, and Daniel, can you post a screenshot of every segment of that "settings" window you posted above? Last edited by Biel Bestue; August 25th, 2008 at 05:54 PM.

August 23rd, 2008, 07:36 PM	#467
Daniel Lipats Major Player Join Date: Feb 2006 Posts: 260	The IRC-30 filter here: IR cut-off filter The filter I'm using right now cuts out red light, and when compensating with white balance it increases the noise by boosting the signal. Furthermore, the filter cuts out an additional 50% of all visible light. The camera is not performing as well as it should be. I'm not sure which filter I have. My results are similar to: http://www.dreamstonestudios.com/per...industrial.JPG Here is a chart with the IRC-21 (cheaper filter) http://www.dreamstonestudios.com/per...umix/IRC21.JPG Finally, the IRC-30 (recommended filter) http://www.dreamstonestudios.com/per...umix/IRC30.JPG Images were provided by Sumix

August 24th, 2008, 01:36 AM	#469
Eric Wu Regular Crew Join Date: May 2007 Location: Taiwan Posts: 32	Hello Daniel, Can you confirm that the camera can be set to run 1920x1080, 24fps, 1/48 shutter speed (exposure time = 20.833ms) and 12-bit output, at the maximum pixel rate (74.76 MHz)? I think this is the most common mode if we are using this camera for digital cinema works. To minimize the rolling shutter effect it's crucial to run it at the maximum pixel rate. Thanks!

August 25th, 2008, 12:04 AM	#471
Eric Wu Regular Crew Join Date: May 2007 Location: Taiwan Posts: 32	That's great news, Daniel. I noticed the exposure showed 0.769128ms, which is about 1/1300 shutter speed. I suppose it's the minimum value, isn't it? Otherwise it wouldn't make sense. I'm planning to order one of the camera and write my own software. What I have in mind is recording uncompressed 12-bit RAW, real-time preview while recording, and a touch-screen UI like the SiliconDVR's. Thank you for sharing the informations and doing the tests.

August 25th, 2008, 12:13 AM	#472
Daniel Lipats Major Player Join Date: Feb 2006 Posts: 260	Eric, I'm not sure how to interpret the exposure value. That is in fact the maximum setting. I did not try to override with a manual input but I don't think it will work. The maximum exposure value depends on the set frequency, at 10 MHZ it peaks at only 4.98 ms or so. I'm going to try and order the IRC-30 filter tomorrow and figure out a way to mount it. The filter should make a considerable improvement to the picture quality.

August 25th, 2008, 03:01 AM	#473
Eric Wu Regular Crew Join Date: May 2007 Location: Taiwan Posts: 32	I'm no expert but I think an optical low-pass filter is needed to eliminate aliasing. So maybe it's these OLPFs incorporated with IR cut-off function that you'll need: Optical low-pass filter

August 25th, 2008, 08:00 PM	#475
Eric Wu Regular Crew Join Date: May 2007 Location: Taiwan Posts: 32	Aliasing and Moire patterns Moiré pattern - Wikipedia, the free encyclopedia I think most hi-end digital cameras have OLPF. It's likely the original Sumix filter is one, too.

August 26th, 2008, 03:04 AM	#476
Biel Bestue Regular Crew Join Date: Jul 2005 Posts: 96	yeah i know that, that's why i suggested the use of that "new" patern in the bayer filter, but i guess that is not up to sumix but up to the maker of their imagers, that patern could get the same information from half the numbers of photosites, so we would be getting double amount of information, so a pixel binning thechnique should do to combat aliassing, but i gues sumix don't print the bayern patern in the imagers of their cameras

September 4th, 2008, 06:20 PM	#477
Daniel Lipats Major Player Join Date: Feb 2006 Posts: 260	Quick update, I ordered the IRC30 filter earlier this week and it will be coming in the mail tomorrow. I will try to find time this weekend to shoot a few more tests.

September 6th, 2008, 04:44 PM	#478
Daniel Lipats Major Player Join Date: Feb 2006 Posts: 260	Here are the results from earlier today, shot with the new filter. Natural light only. http://dreamstonestudios.com/persona...es/IRC30/1.jpg http://dreamstonestudios.com/persona...es/IRC30/2.jpg

September 7th, 2008, 11:22 AM	#479
Gottfried Hofmann Regular Crew Join Date: Jul 2007 Location: Erlangen, Germany Posts: 30	Daniel, do you have an idea where the pattern on the corner of the clock comes from?

September 8th, 2008, 12:03 AM	#480
Eric Wu Regular Crew Join Date: May 2007 Location: Taiwan Posts: 32	Hi Daniel, These pictures are gorgeous! To my eyes the resolution and dynamic range are very good. Even better if you can upload some footages. The colors are not very different from your last pictures, though. Which is not a bad thing IMO. Raw data directly from the sensor are not optimized for human vision. Those Sony, Panasonic video cameras do a lot of processing like color matrix, white balancing, curves, before outputting the image. But those can all be done in post. recording raw data keeps the maximum flexibility for post processing. There seem to be debayering artifacts. I'm not sure if that's what Gottfried Hofmann refers to but I think it can be easily fixed by choosing a more sophisticated debayer algorithm.