Russian KB VITA kindly sent me a video of its camera that uses GSENSE400BSI sensor. The video was shot at moonless night, hence no shadows there. The camera has f0.95 lens and set at 22fps and 40ms exposure time:
Seems like exposure is not fixed. What's with the defects?, you'd think the whole row or column would be bad, why is the row partially bad? SNR = 49dB anyone else thinks this is low? Also, PRNU = 1.5% seems high...
The exposition is not constant, because the brightness of the ground and sky is very different, the exposure changes when the camera is moved to the sky. SNR does not affect sensitivity. The sensitivity is determined by the "noise read" that this sensor nread 2e. PRNU does not affect in low light scenes and it can be adjusted for bright scenes.
Where do you see sub electron read out noise? It says it's 2e- and the noise is very visible. Does the analog gain change in this video too? Seems like in certain shots the noise changes dramatically...
"virtual zero DC" ??? This sensor has a tremendously high DC! Have a look at the DC of a state-of-the-art (2018) CMOS sensor, e. g. that one from Panasonic: https://astronomy-imaging-camera.com/wp-content/uploads/1600mc-cool-dark-current-vs-T1.jpg -dkf
Pixel size is 3.8µm. But you should put the DC in relation to the sensor area. Then the DC for the GPixel is ca. 1650 e-/s/mm^2 and for the Panasonic it's ca. 26e-/s/mm^2 (extrapolated to -50°C) -dkf
how many lux light?
ReplyDelete2mLux, according to Wikipedia:
Deletehttps://en.wikipedia.org/wiki/Lux
Seems like exposure is not fixed. What's with the defects?, you'd think the whole row or column would be bad, why is the row partially bad?
ReplyDeleteSNR = 49dB anyone else thinks this is low? Also, PRNU = 1.5% seems high...
The exposition is not constant, because the brightness of the ground and sky is very different, the exposure changes when the camera is moved to the sky. SNR does not affect sensitivity. The sensitivity is determined by the "noise read" that this sensor nread 2e. PRNU does not affect in low light scenes and it can be adjusted for bright scenes.
ReplyDeleteYouTube video quality 720p and compression is terrible. Is original available?
ReplyDeleteSee the video file below. This is what I've been sent:
Deletehttps://cloud.mail.ru/public/7nfY/if4pWk6Yd
If you remove the IRCut filter of a Sony A7s, you should be able to get much better results.
ReplyDeleteReally? Why does the IR cut filter has a role to play here?
DeleteQE=95%@560nm, GSENSE400BSI
Deletefrom link:
ReplyDeletehttps://habr.com/post/374163/
video
https://cloud.mail.ru/public/B1BK/fokxGJMPz
Is it the same camera?
Yes, it's the same camera, but only earlier winter tests with an F/1.2 lens. SWIR camera is also our development.
Deletewhat cameras on video? are these three different cameras?
Deletewith sub electron RON and virtual zero DC, the 95% peak QE can not stand for comparison.
ReplyDeleteWhere do you see sub electron read out noise? It says it's 2e- and the noise is very visible.
DeleteDoes the analog gain change in this video too? Seems like in certain shots the noise changes dramatically...
"virtual zero DC" ??? This sensor has a tremendously high DC!
DeleteHave a look at the DC of a state-of-the-art (2018) CMOS sensor, e. g. that one from Panasonic:
https://astronomy-imaging-camera.com/wp-content/uploads/1600mc-cool-dark-current-vs-T1.jpg
-dkf
What is the pixel size of this Panasonic sensor? Is it 11um?
DeletePixel size is 3.8µm. But you should put the DC in relation to the sensor area. Then the DC for the GPixel is ca. 1650 e-/s/mm^2 and for the Panasonic it's ca. 26e-/s/mm^2 (extrapolated to -50°C)
Delete-dkf
i think about: CMOS-Chip (Panasonic MN34230) 3.8*3.8u
Deletehttps://www.astroshop.de/astro-kameras/zwo-kamera-asi-1600-mc-pro-color/p,56571#tab_bar_1_select
I think that this comment is related to Sony A7S sensor ...
ReplyDeleteWell, if "virtual zero DC" is a nice circumscription for Sony's "star eater" problem, then the comment makes sense ;-)
Delete-dkf
https://www.youtube.com/watch?v=J9rgtz0vE_c
ReplyDeleteFPS?
DeleteMilky Way, fish-eye, gsense400 (kbvita)
Deletehttps://www.youtube.com/watch?v=MzdL9S_yh0o&list=UUg1-Iwu349iPhzBON9NVzhA&index=7
I do not see any satellite
Deletevery long exposure