FS7: Made terrible mistake, saved by Davinci v14

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Publimix

Veteran
My standard setup is Cine-IE slog3.

But, inside a dark fish market I had to use LED light and use the available fluorescent lights. So I decided to film in Custom. White card, color card, all used.

Afterwards I found out that the ISO setting was ISO 16.000

So almost everything was filmed with the most terrible noise.

I tried the noise reduction in Davinci Resolve 14 at maximum settings and it works (enough for me, I only need a few seconds of footage). vv1_1.32.1.jpgvv2_1.32.2.jpg

Davinci is massively improved (beta 2) reads mp3, and the playback is much much faster, DJI, Gopro footage mixed with AVCHD no problem, smooth transitions.

So this beta saved my day.
 
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What are the specs on your editing system and how much faster does v14 run?
I'm wondering if it will run OK on my late 2013 IMAC 14,2, 3.5Gz, i7, 32G memory w 4G NVIDIA GeForce GTX 780M. Especially for 4K.

Lenny
 
Publimix said:
So this beta saved my day.
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Pretty impressive NR in those stills, glad to hear it helped you out of a VERY tight spot. So tight in fact, that I must admit that if I'd found myself in a similar situation, I'd have been tempted just to trash the clip(s) and blame a critical hardware failure - good persistence!

Do you have a link to any moving (de-logged?) images from that shot? That's where I sometimes find the ugliness limit of NR really shows...

Cheers,

jason
 
Reminds me of the time I accidentally shot an indoor wedding on 5600K ( B & W vf in those days ), spent two days sick to my stomach over it, and then received a call from the groom informing me of how much his new bride loved the "romantic" look that I, in my brilliant artistry, had chosen for their wedding video.
 
But I really doubt that there would be any appreciation for this awful color noise.
Note to myself: avoid ISO 16.000 on FS7 under all circumstances! :)

Alex
 
And switch for Gain in dB for Custom mode, for god's sake (if your background is video, not stills).
:)
Piotr
 
Do you mean 16,000 ISO?! Does the camera really go that high?

At the camera's native 1000 ISO and with a T/2 lens you can shoot in circumstances where it's physically starting to get hard to see with your own eyes. What kind of hellish situation was this market, that the picture is still so underexposed?
 
LennyLevy said:
What are the specs on your editing system and how much faster does v14 run?
I'm wondering if it will run OK on my late 2013 IMAC 14,2, 3.5Gz, i7, 32G memory w 4G NVIDIA GeForce GTX 780M. Especially for 4K.

Lenny
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PC based, Intel i7 5820K 3.3 ghz 32 gb RAM windows 10 and 2x ssd cache and software disks. Version 14 is a lot faster than version 13 (12,5) esp. playback. Also new sound panel and plays mp3.

The great difference is playback Gopro and DJI files, very smooth now, and playback transitions is now a lot better.

I would say 5-10 times faster than before.
 
RealJEDI said:
But I really doubt that there would be any appreciation for this awful color noise.
Note to myself: avoid ISO 16.000 on FS7 under all circumstances! :)

Alex
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The problem was that I got used to Cine IE, when I switched to Custom the settings for auto Gain was wrong. AGL: Auto Gain Limit was set to 16.000.

Somehow the camera was on auto exposure too.

That is the combination for disaster, filming with a cameralight, exposing right (and not looking for the iris setting or ND filter setting.) The camera does it's job by pushing the Gain. And voila noise.
 
Martin.G said:
Whats the difference between gain and iso?
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For us old farts, video cams had a similar silver toggle switch, which boosted the sensor in dB of gain. ISO/ASA is a film stock measurement. FS7 caters for both.

Rough guide nicked from Abelcine, based on FS100, here:

ISO-dB gain.jpg
 
Yeah - looking at this table again I keep wondering why log gammas on all cams I have (FS7, A7Rii and GH5) are using such low ISO that - expressed in dB Gain - it's negative? I've always believed negative gain will shrink DR, which seems counter-productive to the very purpose of log gammas...

Piotr
 
As with audio, "0" gain is not zero. It is a reference gain level for a specified light level hitting the sensor. That establishes the base DR , ISO, SNR specification at the standard middle gray reference.. Increasing gain always decreases DR because it raises the noise floor. Log curves compress shadow levels, essentially progressively raising gain on a curve from a maximum at the bottom to no gain at around 20-30% waveform levels or so. Negative gain in this context is reducing the middle gray scope reference for correct exposure to preserve highlight range.
 
moldcad said:
Yeah - looking at this table again I keep wondering why log gammas on all cams I have (FS7, A7Rii and GH5) are using such low ISO that - expressed in dB Gain - it's negative? I've always believed negative gain will shrink DR, which seems counter-productive to the very purpose of log gammas...

Piotr
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Well, that chart is rated or the fs100.....

I believe the numbers would shift slightly based on the cameras native ISO? For example the FS7 has a native rated ISO of 1000, so that would be it's zero dB, right?
 
Publimix said:
Somehow the camera was on auto exposure too.
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Seriously? How you could possibly do a whole shoot with the camera on auto-exposure and not realize it? I think most people would notice a problem like that in the first 10 seconds. Sounds like you need a pre-flight checklist that covers all the major camera settings. I've created these for clients before who have multiple people who use the gear and it has been a big help to them in avoiding mistakes such as this with exposure, white balance, shutter speed, picture profiles, etc.
 
broughtonfilm said:
On the subject of ISO vs gain: http://www.xdcam-user.com/2016/01/iso-fiasco/
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Once again, he takes information I've been saying for many years in my camcorder training videos and workshops and paraphrases it as if was his own idea. Look back further in the records and you'll see that he only recently started advising against using ISO on video cameras. I've been consistently warning against it since at least the F3.
 
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