- Posts: 50
- Joined: Mon Nov 19, 2012 8:03 pm
Hello BMC users!
A pair of days ago I have read a next topic on bmcuser.com:
http://www.bmcuser.com/showthread.php?1 ... mera-WoW!!!
It is related to fpn and noise after changing firmware. I had made some test and _no success_ BUT found interesting depencency ratio of noise vs camera working temperature.
I want to share it with you because I found it very exiting!
First of all let me show you my screengrabs when I tested all all of noise and FPN things.
I need to say about this pictures first or about my test methodology.
All test was completed on 1.9.8 firmware. I have recorded 4K RAW dng files with various ISO and various camera temperatures. After that I dropped the dng files into Photoshop and when ACR opened I increased the Exposure to +3 setting to better watch the result. I know that in ACR applies by default some sharpening and color noise reduction but I just leaved it as is (Color NR = 25) in all cases.
Than I opened the dngs in Photoshop with Adobe RGB color profile applied and saved as 16 bit TIFF files. Than files was cropped for comparison and showed to you with 100% zoom (I mean 1:1, no zoom).
So here the test results:
1. Camera just turned on with the room temperature (about +24°C):
Don't forget! I have raised exposure in ACR to +3 to look like that.
2. Camera worked about a hour. I have no idea what temperature it was but by the hand it feels like very warm:
As you can see the more camera temperature the more noise (and FPN) it generates. So I decided cool it down to possible deggrees.
As I see at blackmagicdesign.com operating temperature of the camera allowed is 0°C to +40°C (+32°F to +104°F):
https://www.blackmagicdesign.com/produc ... techspecs/
So I decided to go stright to almost 0°C. Luckily weather in our region is pretty match my requirements. I mean it cold and dry. So I leaved the cam at the cold unheated room for about a hour and half. After that time it was very cold by the hand feeling. I think it was about +3°C or +5°C. I recorded the RAW again and ingested it in Photoshop.
MY JAWS ARE DROPPED!!!
Look yourself:
Here the dng files from cold shooting:
https://www.dropbox.com/sh/nsd3tddy2ft4 ... oT9-a?dl=0
I never saw anything clearer like these! It just crazy cleanest image! You can shoot at ISO800 with that temperatures. And it looks better than ISO200 in normal room temperatures! I attached the comparision pics:
TIME TO BUY SOME WATER OR LIQUID HYDROGEN COOLING SYSTEM FOR BMPC4K!!!
P.S. Night shootout is coming... "Waiting for the night" © dm.
WARNING!!! Don't forget that cooled down technics need to be warmed about a hour or two to work in normal temperatures because you can get the humidity condensate dropped to electronic parts!!!
A pair of days ago I have read a next topic on bmcuser.com:
http://www.bmcuser.com/showthread.php?1 ... mera-WoW!!!
It is related to fpn and noise after changing firmware. I had made some test and _no success_ BUT found interesting depencency ratio of noise vs camera working temperature.
I want to share it with you because I found it very exiting!
First of all let me show you my screengrabs when I tested all all of noise and FPN things.
I need to say about this pictures first or about my test methodology.
All test was completed on 1.9.8 firmware. I have recorded 4K RAW dng files with various ISO and various camera temperatures. After that I dropped the dng files into Photoshop and when ACR opened I increased the Exposure to +3 setting to better watch the result. I know that in ACR applies by default some sharpening and color noise reduction but I just leaved it as is (Color NR = 25) in all cases.
Than I opened the dngs in Photoshop with Adobe RGB color profile applied and saved as 16 bit TIFF files. Than files was cropped for comparison and showed to you with 100% zoom (I mean 1:1, no zoom).
So here the test results:
1. Camera just turned on with the room temperature (about +24°C):
Don't forget! I have raised exposure in ACR to +3 to look like that.
2. Camera worked about a hour. I have no idea what temperature it was but by the hand it feels like very warm:
As you can see the more camera temperature the more noise (and FPN) it generates. So I decided cool it down to possible deggrees.
As I see at blackmagicdesign.com operating temperature of the camera allowed is 0°C to +40°C (+32°F to +104°F):
https://www.blackmagicdesign.com/produc ... techspecs/
So I decided to go stright to almost 0°C. Luckily weather in our region is pretty match my requirements. I mean it cold and dry. So I leaved the cam at the cold unheated room for about a hour and half. After that time it was very cold by the hand feeling. I think it was about +3°C or +5°C. I recorded the RAW again and ingested it in Photoshop.
MY JAWS ARE DROPPED!!!
Look yourself:
Here the dng files from cold shooting:
https://www.dropbox.com/sh/nsd3tddy2ft4 ... oT9-a?dl=0
I never saw anything clearer like these! It just crazy cleanest image! You can shoot at ISO800 with that temperatures. And it looks better than ISO200 in normal room temperatures! I attached the comparision pics:
TIME TO BUY SOME WATER OR LIQUID HYDROGEN COOLING SYSTEM FOR BMPC4K!!!
P.S. Night shootout is coming... "Waiting for the night" © dm.
WARNING!!! Don't forget that cooled down technics need to be warmed about a hour or two to work in normal temperatures because you can get the humidity condensate dropped to electronic parts!!!