What is your ISO at 18dB gain??

G

G.P.

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Ok... my F3 says my 18dB gain is ISO 3200.... I keep reading on the web that others say its 6400....


Is my F3 numbers wrong?

What does your F3 say at 0dB ? Confused.
 
different gammas have different sensitivities. Rec 709 is more "sensitive" than cine gamma.
 
well I quite literally mean what does your camera say when you go to +18dB does it say 3200 or 6400 iso? mine says 3200
 
My camera reads the same as yours. It will also read out the same ISO which ever gamma curve you are using even though some of the cine gammas are almost a stop less sensitive. Therefore I don't find the ISO read out any more usefull than db read out. Have you notice the camera changes the ISO when go into Varispeed so there is no exposure change. I'm not sure I like that, but it is so noise free it doesn't really matter.
 
ITs very odd in that way.

VERY Odd.

But it is what it is. not a huge fan, but from what i understand sony optimizes the sensor for best performance.
 
Sony customizes their gamma curves at different sensitivities for optimal performance. When they rated the sensor, they were probably rating it conservatively in a cinegamma setting, and might have "accidently" or maybe on purpose carried over to all 24p gammas in the menu. Hopefully the next firmware update will fix the iso discrepancies. but base sensitivity in 709 IS 800, as andy shipsides has proven it with one of his vids. and your 18 db is at 6400.

interestingly enough when you overcrank, the numbers on your sensitivity change too, somebody should check if those numbers are accurate...
 
hmm so then if im in 709 i should be seeing a number change to the ISO ratings? I had no idea the large difference between the two. I need to check this out now...
 
The major reason to use ISO is to correlate the camera sensitivity with a light meter. In camera gain or ISO ratings are not useful for this. You have to shoot tests with the particular camera settings to see what matches up best with the meter readings.
 
I understand what Sony is doing in why they state the ISO the way they do, but I disagree with it. They are "protecting you" from clipping out. But I like to go by my middle gray and trust my own skills. Here's how I rate the camera:

At 0db the camera is 800 ISO.
At +6db it is 1600 ISO.
At +12db it is 3200 ISO.
At +18db it is 6400 ISO.

BTW, Andy agrees with me on this. Sensitivity is sensitivity. Headroom is another matter entirely.
 
It shows 3200 in 25p and 6400 in 50i or the usual 30p and 60i ... Makes sense ... More frames ... Twice as much light ... Well if you put it simply ...
 
Mitch Gross said:
I understand what Sony is doing in why they state the ISO the way they do, but I disagree with it. They are "protecting you" from clipping out. But I like to go by my middle gray and trust my own skills. Here's how I rate the camera:

At 0db the camera is 800 ISO.
At +6db it is 1600 ISO.
At +12db it is 3200 ISO.
At +18db it is 6400 ISO.

BTW, Andy agrees with me on this. Sensitivity is sensitivity. Headroom is another matter entirely.
Click to expand...

Mitch, this is I'm assuming in REC709? Because if thats also in Cinegamma then my camera is definitely showing the wrong numbers on the screen. My Base ISO is 400 at 0dB
 
Giuseppe Pugliese said:
Mitch, this is I'm assuming in REC709? Because if thats also in Cinegamma then my camera is definitely showing the wrong numbers on the screen. My Base ISO is 400 at 0dB
Click to expand...

dont' trust the numbers that are showing on the screen. Andy clearly showed with a chart and light meter what the ratings are at every level of DB. they are exactly what mitch just stated. Hopefully sony fixes this on a upcoming firmware update. it's adding confusion where there really shouldn't be, and it's kind of ass backwards to try to protect the user from clipping, then they have a professional cinealta camera. They should be trusting that their users are professionals, and be accurate on their displays and readings. It makes it look like there are other motives even if they're isn't.
 
Sensitivity is sensitivity; it doesn't matter what gamma curve. Sony is trying to protect the user and in the end they are following the technical spec definition of ISO, which is based on a formula that includes an offset from the white clip point. But you , me and anyone else I know does not use a light meter in this way -- we care about middle gray. So go forth with the ratings as I listed and you'll be fine.
 
Ok to clarify my question a bit more... I am not looking for the ACTUAL rated iso of the camera. I'm asking what ISO does everyones camera go up to in cinegamma mode at 24p?

With Cinegamma 1 and 24p setup my max ISO that my camera goes up to says 3200 on the screen NOT measured. Can someone else take there F3 put it on cinegamma 1 and 24p and tell me what their max iso is ? I just want to make sure of something.
 
Off topic but, Hey Mitch, do you guys have a price and availability time yet, for the top handle and base plate from NAB.
Thx.

And P.S. for Tim.
Speaking of the plate how did you like it on your shoulder, did it seem to be in the right place for comfort and balance if rear weight is correct with a battery. (I know that cinedeck was on and prob a little odd for balance) But.. overall you think it was do-able?
 
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