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Gio Scope Tool vs The Zone System

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Mike Quill

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I'm having a little trouble understanding how the Gio Scope Tool compares to The Zone System: http://www.normankoren.com/zonesystem.html

Specifically, why is middle grey mapped to stop 11 as opposed to dead center on the scale (8.5)? This implies that there are only 5 stops available above middle grey, but 10 stops below. Why not stick with the Zone System scale and keep middle grey in the middle (Zone 5)?

Thanks,
Mike
 
The stops shown on the gio scope are the sensor response, mapped in stops. Its an entirely different scale and number of graduations to a traditional zone system, however you can adapt the concept.

I advise people to shoot tests to establish their own preference, particularly in establishing their tolerance for shadow noise. Its important to follow these tests through to a final image in a final viewing environment. A quick look on the camera LCD, or even in Redcine does not tell the story.

Once you've got a handle on which stop or stops you consider to be your preferred cut-off, you can then bias your mid-grey to the centre of that range, if you wish.

Stop 11 being the default mid-gray value plays very nicely with Dragon's image characteristics. If you're used to using a light meter, I'd strongly recommend shooting according to Red's gio-scope recommendation of mid-gray - you'll probably feel the image is a little hot, but that gives tremendous advantage in IQ across the board, from noise to compression.
 
Ok so it's safe to assume that the specific details of the Zone System don't apply to Gio Scope? For example, caucasian skin doesn't necessarily fall one stop above middle grey, i.e. Zone 6 when using the zone system and 'stop 12' when using the Gio Scope system?

I understand that this Gio Scope tool is specifically designed for Red and therefore very effective, but wouldn't it have been more straight forward and in line with the history of how one exposes an image to implement a traditional Zone System tool for using in conjunction with a spot meter? Sort of feels like reinventing the wheel.
 
It's still fair to set skintone a stop over mid grey. Bear in mind of course that the zone system in a classical interpretation of one zone=one stop, does indeed tally with the Gio scope, it's just that the camera has a bunch more than the 10 stops available that the zone system describes. If you choose to shift your ten zones down from the top of the exposure range on your own preference, or stretch your interpretation of either end of the zone system, then that's totally your choice. Expect more grain as a result of lowering your chosen mid grey through the exposure though.
 
I don't run beta firmware for jobs, but I'm gonna install today to see how this GioScope works with my light meter. Seems like it's the most informative way to see what's going on exposure wise. Is there a reason I should revert back to a release build before my next paying job or is this beta stable?
 
Jake Wilganowski said:
I don't run beta firmware for jobs, but I'm gonna install today to see how this GioScope works with my light meter. Seems like it's the most informative way to see what's going on exposure wise. Is there a reason I should revert back to a release build before my next paying job or is this beta stable?
Click to expand...

If you have any insecurity you should always run the release build.

However, truthfully, I pretty much have been running beta builds on my camera as long as I've been a Red owner. I test the builds hard before shooting with them, but I seem to always be itching to start using new features on set. GioScope for instance has been real nice for the shoot I'm currently on.
 
Phil Holland said:
If you have any insecurity you should always run the release build.

However, truthfully, I pretty much have been running beta builds on my camera as long as I've been a Red owner. I test the builds hard before shooting with them, but I seem to always be itching to start using new features on set. GioScope for instance has been real nice for the shoot I'm currently on.
Click to expand...

Ha - glad you posted that, Phil, since I, too, have pretty much always run beta builds. I have never had a single issue.
 
the gioscope is literally my favorite tool now to use on set. always using it to judge exposure. helped alot last night when shooting some very contrast and low-key scenes.
 
Wait... Wrong thread... (not enough coffee today).

Actual question -- is there a tutorial on how exactly to apply/use GioScope effectively?
 
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Red officially says use stop 11 as mid-grey
 
Phil Holland said:
What John said. And always remember Middle Gray (18% Gray) "isn't" 50% Gray.
Click to expand...

What Phil said. And always remember that the Zone System is about achieving a final output that expresses the full dynamic range of the print. And also always remember that the Zone System was developed as a system based on well-known characteristics of both black-and-white negative film and black-and-white paper prints. Things get funky when the sensor can capture more DR than can easily be displayed, either via display or physical print rendering. And Adadm's book The Print explains how and when one may wish to stretch or shrink a negative's contrast curves in order to achieve a balanced, beautiful final result. The best use of the GIO Scope is to get as rich and thick a "negative" as you can; this then gives the colorist the maximum freedom and flexibility to achieve a balanced and beautiful output, which is the ultimate goal of the Zone System.
 
On MX, Dragon or both?

If so, does that mean if you enable "stop 12" (one stop above mid-gray as caucasian skin-tone) as your anchor point, you'd be in a really good position exposure wise?

Michael Tiemann said:
The best use of the GIO Scope is to get as rich and thick a "negative" as you can; this then gives the colorist the maximum freedom and flexibility to achieve a balanced and beautiful output, which is the ultimate goal of the Zone System.
Click to expand...

But how? Around what Anchor point given the greater DR and Colour (and displays) of the video footage? Like if I make my 18% gray at stop 11 (~45%), does that not mean I'm needlessly clipping the highs? I mean, Gio is ISO independent, right?
 
Mike P. said:
But how? Around what Anchor point given the greater DR and Colour (and displays) of the video footage? Like if I make my 18% gray at stop 11 (~45%), does that not mean I'm needlessly clipping the highs? I mean, Gio is ISO independent, right?
Click to expand...

The reference of middle grey at the 11th stop is to overexpose the RAW. It is actually exposing for a lower iso maybe 250 or 320 which have less highlight retention, but because you are giving the sensor more light when exposing for those isos, you are increasing the fidelity of the negative, that means more distinct and vibrant colors, and more room to push in post. If your scene is controlled, the 5 stops above middle grey is plenty of headroom and will yield a better looking image. The 11th stop reference is useful if you are looking for the cleanest image and beefiest negative.

There isn't a sweet spot for the very best color and the most even distribution of stops of dynamic range, you have to preference one or the other. The good thing about dragon is that at 250 and 320 there is still enough room that highlight retention is not really that much of a problem so rating low in most conditions is a win win. But if you really want the most even dynamic range choose a lower reference point in gio scopes. That will increase highlight retention and create more noise, and lower color fidelity. Then again Dragon with the low light OLPF at higher iso can be pretty clean and can produce great color as long as there is minimal contamination and a preferable WB. So Dragon to me at least is so good that theses pros and cons of exposure, DR, and color, have been reduced to pretty subtle caveats.
 
I agree, they are basically mapping mid grey higher to give the sensor more light
 
A spot meter, an 18% grey chart and GIO SCOPE turned seems the way to figure out what ISO/FSTOP/shutter that value is mapped at.

I don't think it is a conspiracy theory or rocket science to figure out. There might be many reasons for the logic of the layout of the tool. IT's been in several beta build for a long time.

Battistella
 
I actually just did this out of curiosity.

Here is what I found.

On an 18% grey card lit to ISO 800 F8.0

Spot Meter reading, centre of the card

800 ISO, 172.8 shutter, 24FPS F8.0

Camera
800 ISO, 172.8 shutter, 24FPS F8.0

With the above settings the GIOSCOPE lights up at #10


with only GIOSCOPE #11 turned on GIOSCOPE engages GREEN at F5.6 ONE stop over Metered Light on 18% grey.

So, in my fast crude test GIOSCOPE number 10 equals 18% grey at lit to F8.0 ISO 800
 
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