Dynamic Range Comparison - Canon C200 vs Canon R5c

[DustinSchmidt]

I was curious how my Canon C200 would look in some direct comparisons to my R5c. I've shot both cameras a whole bunch, but I haven't pointed them at the exact same thing, under controlled circumstances.

There are certainly more scientific tests out there, and plenty of comparisons between these cameras and other cameras, but I was curious to do some of my own testing. There's nothing like actually doing the work for yourself to find out how the image responds.

If you're also interested in these cameras, you may want to check out some of the results.

 

[morgan_moore]

Sorry to say this vid tells me nothing.

You have those black holes at the side where you could up a big zoom of a bit of the image.

The scen has how many stops of DR - how did you light it measure it.

Then you talk about correct exposure?

What is correct exposure - how do you make a correct exposure, how do you demonstrate you are making a correct exposure?

How are you correcting an image? what is your method of correction? How do we know your methodology is consistent?

proscess as clog 2 - how do you 'process' an image?

 

[DustinSchmidt]

Hi Morgan, thanks for commenting. You're right, some more information would be helpful, so I'll try to answer what I can for you. Appreciate the dialogue.

I shoot a lot of interviews, so I wanted the framing to reflect a normal setup I might have. I also wanted the gray backdrop in frame to see when and how the noise would start to show itself as I stopped down, and the darker areas tend to show that first. I usually like to light in a practical space and use the surroundings, but in this case a backdrop had to suffice for this test.

Great question regarding dynamic range. In retrospect, the title of this is mislabeled.

It's an exposure latitude test and not a measure of dynamic range. I don't own a xyla chart or anything like that to do a true dynamic range measurement on my own.

To test the latitude I used the CineD method of an arbitrary value of around 60% luma value (in the waveform) for the subjects’ forehead in a standard studio scene.

The base exposure was achieved by lighting to an F/11 at iso 800. Overexposure was then calculated by opening up the iris by one stop at a time until 4 stops over. f/11 (base), f/8 (1 stop over), f/5.6 (2 stops over), f/4 (3 stops over), f2.8 (4 stops over).

The two images were then lined up in the same frame and the overexposed images were normalized by aligning the waveforms. The exposure offset was accomplished by adjusting the exposure in the raw tab of Resolve. For example, to normalize the shot that was 2 stops over back to the base exposure, the exposure dialogue box in the camera raw tab was set to -2. For 1 stop it was set to -1, for 3 stops over it was set to -3, etc.


When I say "processed as clog 2" the camera raw settings were set as shown in the photo above. Canon Cinema gamut, clog2, iso 800 (for the stuff shot at 800). For the base 3200 iso it was all the same as shown above, but the iso was of course 3200.

The only color correction/processing was to take the raw footage and apply the Canon provided lut from their website for CinemaGamut_CanonLog2-to-BT709_WideDR_65_FF_Ver.2.0 to normalize the footage.



Hope this helps at least shine a bit more light on the process.

 

[morgan_moore]

Good to see there is some logic and consistency

But at around 7.40 you are 'over exposing' the C200 by three and four stops

Yes you descirbe the image quality as 'holding up fantastically'.

I would suggest it is better than 'normal' and indeed fantastic. Dig into a dark area vs the 'correctly/normally exposed' (3-4 stops darker) and you will I guess see that the quality is not just 'good' but super clean in the shadows

In fact the 'three/four stops 'over' image is therefore vastly superior to a 'correct' exposrue

Now if the image is superior surely make that the new correct, because you will go with that supierior for ever now whenever you can beause it is superior, and surely you will normally choose superior

So not checking in 6xzoom the shadow noise maybe you are missing a trick. To see if 'over' is better than 'normal'

Once you decide that 'four stops over' is 'superior' then it becomes your new 'normal'.. which is 3 stops brighter than you old 'normal'. So you have two normals, which is not possible ergo you have no normal.. hence I get cross with those talking about a 'normal' exposure.

Then you start actually having to understand exposure.

-is that white sheet important? If I clip it the rest of my image will be cleaner - is that a worthwhile trade off - m I protecting nothing?
-how would I expose the image if the white sheet were not there at all?
-oh! the white image has some pale but important writing on it that I lose with a more open exposure - how will that impact the general quality?
-what about making a cuttable sequence where interviewer A has no white sheet but person B does have that I need to close to protect? will changing exposure on the two shots cause an inconsistency with noise and feel.. maybe I should go with the darker feel?
-is it worth getting a blade and cutting some light off the white sheet? what if the white is on a lap then held up mid interview?

---

My 'normal' with the C200 is to open up until I see a flattening of the wfm (clipping) then close down a tiny bit.

And that is very different from your 'normal'

Or to let I some stuff clip, with a good concept of what is clipping.. maybe some halogen spots can clip, maybe a whole sky in high key fasion, maybe NOT the wedding dress

How will I sail this ship today?

So lets have a look at those shadows a 800% because without that you are blind after YT compression,

 

[DustinSchmidt]

Great comments, thanks for taking the time to respond in such detail.

I agree with you wholeheartedly. The "normal" exposure is more of a baseline to test against, rather than a hard and fast rule that all scenes should be exposed that way. Knowing what I now know about how the image responds, I can make intelligent exposure decisions based on what's in the frame.

To your point, if I'm not worried about clipping any whites and I'm in a scene that doesn't have anything on the high end of the waveform to protect, then based on my tests I'll now push that exposure up anywhere from 1-4 stops to get cleaner blacks and less noise.

"How will I sail the ship today" is a good analogy since things are always changing from setup to setup. I find that a lot of people never do the work to see what their camera can actually handle and I simply wanted to run some tests that allow me to do that better.

Learned a lot about both the C200 and the R5C during that process that I think will lead to better images moving forward.

 

[DLD]

That light staring right into the camera screws up the exposure for most of the clip's duration ... except when an arm is blocking it.

 

[morgan_moore]

Dustin great you are reading it as i am.

Ive done vids like this and the linguistics usually get in the way of others really getiing where it is going.

“normal” exposure “correct” exposure both irk me.

reference exposure maybe or something else

 

[DustinSchmidt]

That light staring right into the camera screws up the exposure for most of the clip's duration ... except when an arm is blocking it.

Thanks for the comment. Are you referring to the talking head stuff to camera? If so, that's more of a stylistic choice for the piece to camera stuff than frames that are supposed to be representative of testing the camera's latitude. The latitude sections start later on in the video.

 

[morgan_moore]

As it happens often when im dong a test I will indeed plonk a dedo in the corner

(usually blasting a hot circle onto the back wall)

this then opens up discussion of exposing the scene.

-how noisy is it if I stop/nd down and hold the dedo?
-how much cleaner is it if the dedo blows?
-with the dedo blowing do we get horrid off colour doughnuts?

rather like the white paper in the OPs scene but worse.

 

[DLD]

Thanks for the comment. Are you referring to the talking head stuff to camera? If so, that's more of a stylistic choice for the piece to camera stuff than frames that are supposed to be representative of testing the camera's latitude. The latitude sections start later on in the video.

Yes, as you're talking into the camera, the light on the left blows up the exposure. As SMM said above, whatever light might be placed there ought to be pointed at the back wall to give the sense of depth. Whether it's a Dedo, without or without reflectors, is a stylistic choice. To me as a viewer, this setup was distracting.

But only as a viewer.

 

[Tom Roper]

On my BM U12K, the highest ISO setting is 3200 but it is not actual ISO. It is EI. The sensor is recording everything in actual base ISO (800), and all the settings above and below are EI adjustments. It means that changing ISO is no different than pushing exposure in post, the noise is the same. The sensor is 50% clear cells for sensitivity, and the other 50% equally split R,G,B for gamut. The ISO invariance means you control your own exposure latitude, the number of stops above and below middle gray. There is no added gain when changing ISO. It's the same in theory as Sony EI log shooting for my F55 except it overall performs cleaner in the shadows and retains more highlight latitude at the same time. The other feature is False Color tool. With that, more easily than you can with a WFM or histogram I can see exactly when the filament clips independent of the globe on an incandescent lamp. I'm certainly not saying that should be anyone's priority, but it was mine when I was shooting some Christmas Decorations at Hudson Gardens. I wanted to retain all the color saturation of the lights, and reproduce the scene as I remembered it on a dark night, not falsely try and turn night into day. Accordingly, I shot this at ISO 3200 which gives 8 stops of highlight latitude above middle gray, great for the Christmas lights. I adjusted the exposure (12K 60 FPS 180 degree shutter) with the lens aperture, which varied on the shots between f/2.0-f/4.8. I closed down the iris to protect highlights by intention. So this was ETTR with finer control from false color. The shadows are left to fend for themselves. The remaining middle and shadow tones of average scene brightness are as I remembered.

 

[norway]

Just throwing this video into this discussion as well...

 

[morgan_moore]

But its looong.

”look at the wfm open till you see clipping stop down a little. Shoot”

a 10s vid covers it

 

[DustinSchmidt]

Just throwing this video into this discussion as well...

Good timing on this video release, per this discussion. The topic of how to accurately (or even creatively) expose has certainly been going on forever. There's some good info in there though.

Having these discussions on this forum are invaluable. Obviously the clients I shoot for aren't interested in how rating the camera at 1600 instead of 800 will affect the image and its allocation of stops. They just want it to look good on the monitor while the shoot is going on.

As creative and technical people we have these conversations amongst ourselves, in order to produce the best work possible. And then, hopefully, get hired back.

Thanks for all the back and forth on this.

 

[Andy9]

But its looong.

”look at the wfm open till you see clipping stop down a little. Shoot”

a 10s vid covers it

I'd be concerned about consistency doing this. Consistency in terms of noise, colour and contrast depending on where everything is landing on the gamma curve (which is changing shot-by-shot). It's certainly the way to get the cleanest results overall but potentially a lot of work for a skilled colourist.

And are they adding grain back into the cleanest shots? Perhaps it's a simpler process with raw? I've never shot raw.

 

[morgan_moore]

I'd be concerned about consistency doing this. Consistency in terms of noise, colour and contrast depending on where everything is landing on the gamma curve (which is changing shot-by-shot). It's certainly the way to get the cleanest results overall but potentially a lot of work for a skilled colourist.

And are they adding grain back into the cleanest shots? Perhaps it's a simpler process with raw? I've never shot raw.

Your concerns do hold value.

Scrolling back through the thread you will see some I asked questions the OP could ask when considering the scene of a girl and a white bit of paper..
-do I care about saving the information in/on the paper
-how would I expose two shots, one interview subject with paper, and another without

SO if this were a advertorial for paper with some light colours, egg shell paper, pink paper, whatever, the answer is .. well you get me.

--

ETTR has these problems fur sure..
-will the noise be consistent through a sequence?
-will the colour fidelity be good at the top end of the WFM?

IN general I think the first is not a problam.

Either you are doing a formal shoot and will light to a basic Tstop and the noise is consistent
Or you are shooting doc/actuality and the noise will bounce about wherever you put your exposure as your 'real' scenes are all different.
(I spose you could use 'excessive' ND to keep noise consistently high)

In terms of colour fidelity it for sure gets interesting.

'Linear' raw cameras should for handle an exposure put at any point - by exposing right oneis keeping signal away from the noise floor

'Log' or any cameras with the dreaded 'kmee' may lose fidelity above a certainnumber as the curve flattens to 'protect' (fk up) the highlights

That second situation is one I certainly need to test more.

Generally people who jump down the throats of ETTR folk are seeing it as some form of hard clip mantra, in reality clever ettr people are just folk who dont like to see the top 40% of the wfm left blank where other choices could be made.

Overall the main difference is not taking exposure guidance from the appearance of a 'normally lutted, or unlutted' on set monitor but understanding that a swing down in post can happen and willusually produce better results.

 

[Andy9]

Or you are shooting doc/actuality and the noise will bounce about wherever you put your exposure as your 'real' scenes are all different.
(I spose you could use 'excessive' ND to keep noise consistently high)

Sony's variable eND and the FX6's amazingly clean high base of 12800 have really spoilt me in a situation like the one above. If I expose high base a stop over low base, they will be pretty close in terms of noise after grading, so it's fairly easy to stay consistent.

"in reality clever ettr people are just folk who dont like to see the top 40% of the wfm left blank where other choices could be made."

I can imagine an extreme situation where I am shooting a low-key scene and I have no idea what the idea / purpose of the shot is - should her face really be in shadow? In this case yes, maybe I will try and get the 'thickest negative' or whatever but this is the equivalent of me announcing defeat and throwing myself on the mercy of the editor. It's not something I'd choose to make a habit of and I think it would be symptomatic of bigger problems with the project.

If I'm being paid to shoot, I'm generally being paid to make decisions about exposure and I'm sure there are plenty of editors (in doc / news / drama wherever) who would prefer to receive footage which has strong opinions about where mid grey should be rather than the absolute maximum amount of signal to noise available for each shot. It might give them more time to do a better job overall as well.

Now that said, it's likely that even if I was sure about the purpose of that low-key scene described above, I'd err a bit on the side of overexposure - let's say a stop over target unless Roger Deakins is standing behind me and giving me the thumbs up. So maybe we're not so far apart after all but I'd never start from clipping and work backwards.

 

[morgan_moore]

It is a shame that editors can be so ignorant.

 

[Tom Roper]

Here we are again, going in circles about exposure..

Alister in his latest blog says this:

Even though I and many others no longer advocate the use of extra bright exposures at the lower base ISO’s with these newer cameras it really does surprise me how many people believe it is still necessary to shoot up to 2 stops over. It’s really important to understand that shooting S-Log3 up to 2 stops over isn’t normal. It was just a way to get around the noise in the previous cameras and in most cases it is not necessary with the newer cameras.

 

[morgan_moore]

Some thoughts.

-alistair presents no evidence. He could equally say bananas are purple. Or the earth is flat.

-the OP was exploring the C200 which is 'very old'


He may of course have a valid point and other exposure methodologies might add up for equalising noise and protecting more highlights.

I have wondered this (and asked arri) about the 35. Maybe it is so clean that ettr has little value - I can see this might be possible with the Arri 35 but am less convinced that a £2000 sony is clean and uncompressed (not blocky) in the shadows (or smudged to fk by the codec)