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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Black shade temprature experiment.

When you change climate like ging from a hot outdoor shoot into a cold studio, or vice versa. Also when you change frame rate below 24p. like if you want to do undercranked shots and drop to 1 or 2 FPS.

Someone also said when you go up to very high shutter speeds. I do it every day before we start rolling, and if possible during lunch.
 
With the SI2K, the system will prompt for a "black calibration" after changes to sensor area selected ( cropped sensor ) camera setting changes like shutter speed, frame rate, extended shutter for interval recording. I will routinely do it after the camera has warmed up to a stabilised operating temperature and three or four times during the day, even if there are no significant environmental changes. If there are long takes which push the temp higher, I will also do it between takes if I think I need to or if urgency has demanded kicking off with the camera still cold and warming. I like to think of it as a form of insurance. At 2K the process takes about 30 seconds of my time during which other small tasks can be done. At 4K and more, you guys may be finding longer times are required. My personal preference would be if you can fit it in, do it.
 
It takes ~15 minutes at 4k... 30seconds at 2k seems too good to be true. If the process only took 30s (at 4k) I'd do it often, but 15mins is just too long to be convenient.

Timur, any word on the whether your first example was accurate or not?
 
Victor MOREIRA said:
Period.
The guru has spoken.
Graeme is the one "educating" that sensor. So let's go back to work guys.
Click to expand...
Well, also keep in mind that Graeme and Jim have been reluctant to go into much detail on black shading best practices and the science behind it. So it's not surprising that the result is a lot of different users' theories based on personal experiences and anecdotes. It'll probably be awhile before there's any consensus based on hard user data. So I'd say it's time to do more tests :)
 
Mike P. "Too good to be true". I have probably misguided you. The camera I described is not a RED family camera and does not have to deal with so many pixels on the sensor. I was mainly describing my personal preference for "black calibration" which is the SI equivalent of black shading and mapping bad pixels. Up until now, I did not know that it is a 15 minute task with the RED family cameras. It is understandable because of the hugely greater number of pixels and data to manage. I also did not know the RED camera family saves "black shades" to recallable files. The P+S SI2K so far as I know does not do that. Would be nice if it did.
 
Satsuki Murashige said:
Well, also keep in mind that Graeme and Jim have been reluctant to go into much detail on black shading best practices and the science behind it. So it's not surprising that the result is a lot of different users' theories based on personal experiences and anecdotes. It'll probably be awhile before there's any consensus based on hard user data. So I'd say it's time to do more tests :)
Click to expand...
With all due respect, this is why A LOT of people keep messing with their shots. The madman who ignited this and his friend that's the brain behind the Sensor are giving a simple advice. Why would you disagree on that process ? Do they usually misinform us ? Do they want us to keep shooting noisy images ? No. For sure. So i'll stick with this : BLACK SHADE AT WORKING TEMPERATURE. And save my time polishing other aspects of my images. Sometimes life is easier than it seems my friend... Peace.
 
Hey Victor if you disagree with people experimenting calibrating at different temperatures , just don't do it. no need to argue that you disagree.

I have calibrated my Epic when its cold, medium and running hot, and there is a noticeable difference. And that, I believe, was the point of this thread.
 
Robert Hart said:
Mike P. "Too good to be true". I have probably misguided you. The camera I described is not a RED family camera and does not have to deal with so many pixels on the sensor. I was mainly describing my personal preference for "black calibration" which is the SI equivalent of black shading and mapping bad pixels. Up until now, I did not know that it is a 15 minute task with the RED family cameras. It is understandable because of the hugely greater number of pixels and data to manage. I also did not know the RED camera family saves "black shades" to recallable files. The P+S SI2K so far as I know does not do that. Would be nice if it did.
Click to expand...

Crud... I saw you mentioning SI-2k, but then you mentioned 4k, so I figured you were doing it on both cameras.

Alas, it does take 10-20mins to do a black shade on RED cameras. You can only have two black shade maps to recall from -- factory default (which is around 24fps with ~180deg shutter) and User Settings (which is whatever you want.) RED should really allow for multiple (unlimited) number of black shade presets as I would have one for 4k, 3k, 2k, at 1/48th and then the same set at max frame rates/shutter, etc....
 
Mike P. said:
RED should really allow for multiple (unlimited) number of black shade presets as I would have one for 4k, 3k, 2k, at 1/48th and then the same set at max frame rates/shutter, etc....
Click to expand...


Yes, yes, yes.
 
Why does the Phantom 65 Gold black shade so quickly but the Epic take so long? What major difference is going on under the hood of the Epic during the black calibration when compared to the Phantom 65 Gold.

I performed this "hot black shading" discussed in this thread and I noticed a darker image.
 
Seemed to work for me...I was at ISO 2000 with a clean image, which I haven't had before on the Scarlet when black shading at operating temp. I kept the fans in the 30-35% range and it got warm, but kicked on the fan to high when it went too high. At that point, I did the black shade and it seems to be very nice.
 
Shaun Cammack said:
Seemed to work for me...I was at ISO 2000 with a clean image, which I haven't had before on the Scarlet when black shading at operating temp. I kept the fans in the 30-35% range and it got warm, but kicked on the fan to high when it went too high. At that point, I did the black shade and it seems to be very nice.
Click to expand...

Well you should always let the camera run for 20-30 minutes to let it warm up to operating temperature before black shading. So if you turned it on and black shaded it immediately in the past without letting it warm up for a bit that could explain why you are getting a better calibration now that you have warmed it up.

Graeme says the ideal calibration is going to be AT operating temperature and I would tend to believe that ;)
 
Tehben Dean said:
Well you should always let the camera run for 20-30 minutes to let it warm up to operating temperature before black shading. So if you turned it on and black shaded it immediately in the past without letting it warm up for a bit that could explain why you are getting a better calibration now that you have warmed it up.

Graeme says the ideal calibration is going to be AT operating temperature and I would tend to believe that ;)
Click to expand...

In the past, I had let the camera come up to temperature for 30 minutes and this still resulted in a cleaner image. Could be a fluke I guess. Seems reasonable, though.
 
The black shading on Epic takes so long because that part of the firmware is implemented in a 'turing machine' for true future proofing.
I also heard the black shading comes out better if the lens mount is facing Meca during the calibration.

This is all true, right Graeme ? ;)


Brian Robbins said:
Why does the Phantom 65 Gold black shade so quickly but the Epic take so long? What major difference is going on under the hood of the Epic during the black calibration when compared to the Phantom 65 Gold.

I performed this "hot black shading" discussed in this thread and I noticed a darker image.
Click to expand...
 
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