C300: 1DC and C300: where should my grays and whites be on external 0-255 waveform?

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Nicholas Natteau

Veteran
I'm using a SmallHD DP7Pro Oled monitor to view the image coming out of my 1DC and on other occasions on my C300 and I'm shooting in Canon Log mode. As I understand it, in Canon Log my whites need to be at 63% IRE and my 18% mid-grey level needs to be at 32% IRE. The problem is that the DP7 Pro monitor uses 0-255 scale as opposed to 0-100% to measure luminance. SmallHD told me that they're coming out with a firmware update to enable 0-100% scale, but until then I need to know what the equivalent would be in 0-255 terms.

But if in View Assist mode does the 32% grays and 62% whites no longer apply? Is it then the usual 95% white level to beware of instead?

Thanks very much in advance.
 
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I have mentioned it elsewhere, but check to see if your C-log is actually underexposing. Doesn't effect IQ, but is something to be aware of if you exposure gets critical. And I am not refering to the darker appearance of c-log, but actual underexposure. I am comparing c-log video with raw stills, and getting more highlight info in c-log than the raw has, yet c-log has less shadow detail than other video styles.... I can only assume it is underexposing. The difference in about a stop under.

Nobody else seems to be mentioning it, except one guy, Andree, suspects it. I may just have a bad camera, but I think it is in the design. I know that doesn't directly answer your question, but consider it worth being aware of when considering exposure. C-Log has good range, but sometimes, if you really have to nail the exposure...

And regards to View Assist, Canon says: "When using the Canon Log Gamma, it is important that DPs still use traditional light metering techniques and/or scopes to judge exposure. Do not use the View Assist function to make any judgment regarding correct exposure of your final images."

But using light meters, it is good to know that C-Log is changing how the camera behaves by a stop, in case the DP changes picture styles. (of course, histograms and vectors are crucial, but some DP's are purists and wish they were shooting on film....etc)
 
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It is important to be aware that I am getting actual different exposure values in C-Log.

Some people shoot a raw, and go to preview check the histogram for exposure, then start shooting, but this would give me the wrong exposure on my 1dc in clog.

Also, the 1dc does not have a proper video out with VA, though VA definitely gets us close enough for most things. So, I am beginning to wonder the best way to judge critical exposure in clog, on the 1dc, as well.
 
Hi James. Thanks again for your feedback and helpful tips. Now as I understand it, if I were not shooting in C-Log, I would simply need to make sure that my whites are well below 95-100% IRE. But in C-Log, I read that brightest white is actually supposed to be around 62% IRE whereas mid-gray (18% grey) is actually supposed to be around 32% IRE. Yet with VA (visual assist) activated, the normal rule applies: brightest whites at 95-100%. Did I understand you correctly?

Thanks again in advance.
 
Nicholas Natteau said:
Hi James. Thanks again for your feedback and helpful tips. Now as I understand it, if I were not shooting in C-Log, I would simply need to make sure that my whites are well below 95-100% IRE. But in C-Log, I read that brightest white is actually supposed to be around 62% IRE whereas mid-gray (18% grey) is actually supposed to be around 32% IRE. Yet with VA (visual assist) activated, the normal rule applies: brightest whites at 95-100%. Did I understand you correctly?

Thanks again in advance.
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Correct. View assist turned on will give you approximated corrected exposure levels. Canon does not support this method. It is only going to help you get very close. Marvinhello seems to have more experience with this method. Seems fine for those that really know how their camera behaves.
 
do you have a light meter? set the exposure according to the reading (maybe overexpose 1/3-2/3 stops if under low-light.
 
Thank you marvinhello. Yes, I have the Sekonic L-478. Coming from a video background I'm just more familiar with waveform monitors. But I'm eager to learn more about working with lightmeters.
 
Nicholas Natteau said:
Thank you marvinhello. Yes, I have the Sekonic L-478. Coming from a video background I'm just more familiar with waveform monitors. But I'm eager to learn more about working with lightmeters.
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When using a light meter, make sure you test out how your lens and camera setup reacts to the light meter readings. Do under and over exposure tests and write everything down, so when you are looking at footage, you have your notes with you.

Light meters are great for understanding the scene, but the nice thing about VIDEO cameras, is they can tell you exactly what they are doing with exposure. No guess work. (DSLR's not in the same way). One colleague, whom I respect, and can interpret light better than I can, just didn't know where a Red One MX range was, and he too often overexposed, and in challenging scenes he would clip badly. Due to the Red Hate, he just blamed it on the Red, and said I was being techy, by looking at the scopes and wave forms. (I only mentioned it to him in private, never on set, plus he had a great attitude about everything)

Recently the cinematographer for the new Lone Ranger, Bojan Bazelli, ASC, said in an interview: "In the digital world, because you see exactly where the range is when you're shooting it, you can dial in the perfect third-stop or half-stop differences that are crucial to matching," (although, I am sure he was still using a light meter)
 
Thanks again James. In terms of correct exposure then, from what Bazelli is saying, it seems as though a waveform monitor might give you an even more exact reading than a light meter. Thanks for sharing this.
 
Nicholas Natteau said:
Thanks again James. In terms of correct exposure then, from what Bazelli is saying, it seems as though a waveform monitor might give you an even more exact reading than a light meter. Thanks for sharing this.
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They do different things. (sometimes to the same goal, but they are very different in nature, and I do not understand the rationale of people who do not use waveforms and scopes when shooting video)

Typically, a professional video camera's waveform/histogram is going to show you exactly when it is clipping and where your grey card is, etc. So, when getting exposure, I always check with them before final decisions. They allow you to get very brave with the extremes of exposing.

The light meter will help you in many many other useful ways, and is a vital tool in any light designers bag/belt. One does not negate the other, they are best working together.
 
The beauty of shooting in digital is the Waveform monitor. My waveform monitor is constantly on in the LCD. If there is something in the bottom right fame of the scene that I need to be careful about, then I switch off the WFM. You can know which object is at what levels due to the WFM. I am missing the WFM in the EVF of the C300.

As far as videoscopes are concerned, I find it very useful while changing the colour temperature/white balance. I use it more during editing.

The middle gray when using C Log is different. Someone had earlier posted a link to Canon digital learning centre tutorial on exposure. You may like to check that.
 
Yes I totally agree about the lack of waveform on the C300 EVF. I remember Philip Bloom mentioning that in his review of the C300. I was really hoping by now that we would see a Canon firmware update bringing us the waveform display to the C300 viewfinder. I never understood why on the C300 nearly everything you see displayed on the LCD can be displayed on the EVF and not the crucial waveform display. Would it really be that hard to do?
 
Including Waveform in EVF will not be hard. Its a few pieces of code. Developers will jump to voluntarily do it for Canon, if that can help speed up the process. However, it doesn't appear to be a priority for Canon. Even things like offcentre magnification which has been there in the canon DSLRs since donkeys years, is going to be implemented with a six month time from from its announcement during NAB. Apart from big name filmmakers/directors may be Canon has to include a few lesser mortals in its list of people who are given cameras under NDA.
 
indiawilds said:
Including Waveform in EVF will not be hard. Its a few pieces of code. Developers will jump to voluntarily do it for Canon, if that can help speed up the process. However, it doesn't appear to be a priority for Canon. Even things like offcentre magnification which has been there in the canon DSLRs since donkeys years, is going to be implemented with a six month time from from its announcement during NAB. Apart from big name filmmakers/directors may be Canon has to include a few lesser mortals in its list of people who are given cameras under NDA.
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In a sense, I am surprised it is not on the 1DC either, but sometimes these "big" corporations are just smoke and mirrors, in a way. They have surprisingly few staff, and keep everyone busy with other projects. It happens, anyway. (I know nothing about Canon in this regard, just that is my experience with most companies).
 
Also, just a thought, when you punch in for zoom focus on the 1D-C, the external monitor reads only that particular crop. So, if you are on a prime lens, you can use the focus zoom to get up close on a grey/white/chart/face/surface or whatever, and your external monitor with will read that.


Same setup, but different exposures. On a 35mm.


(If it wasn't 4:3, it might even be useful for some HD content when recording to external. Which I really wish the 1D-C had a crop record function. Love having that s16 or 8mm option for some more creative lensing compositions and unique perspectives. )
 
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My comment about the lack of waveform monitor in the EVF stems from the need for stealth shooting. In a number of situations attaching the LCD gives away that I am filming. Else, people think that I am one of those photographers. Also during wildlife filming in dawn and dusk when the light levels are low, I don't want my face to be lit by the light from the LCD and bring attention on myself.

I agree that resource allocation is something every corporation has to grapple with. Someone internally have to feel that a new feature will indeed improve the customer satisfaction or attractiveness of the camera etc. Only then it will be taken up. Also it is a fact that Canon is a pretty conservative organisation and it will never give half-baked firmware unlike some other companies. Infact, I really appreciate that as we can rely on the camera to behave the way we want and not have a mind of its own like an irate spouse. :) So even though some bright young guys in their team may come out with a solution, it has to pass through their own system of checks and balances. I just want the process to be faster. These are fine cameras and slight tinkering will really help in improving the use in several situations.
 
indiawilds said:
My comment about the lack of waveform monitor in the EVF stems from the need for stealth shooting. In a number of situations attaching the LCD gives away that I am filming. Else, people think that I am one of those photographers. Also during wildlife filming in dawn and dusk when the light levels are low, I don't want my face to be lit by the light from the LCD and bring attention on myself.

I agree that resource allocation is something every corporation has to grapple with. Someone internally have to feel that a new feature will indeed improve the customer satisfaction or attractiveness of the camera etc. Only then it will be taken up. Also it is a fact that Canon is a pretty conservative organisation and it will never give half-baked firmware unlike some other companies. Infact, I really appreciate that as we can rely on the camera to behave the way we want and not have a mind of its own like an irate spouse. :) So even though some bright young guys in their team may come out with a solution, it has to pass through their own system of checks and balances. I just want the process to be faster. These are fine cameras and slight tinkering will really help in improving the use in several situations.
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Good words.
 
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