Category: General
Do you shoot video with a Canon EOS DSLR or Canon EOS mirrorless (RF or EF-M) camera? Do you primarily shoot footage using a picture style commonly known as Prolost Flat? Do you edit your video in Adobe Premiere Pro? Have you struggled to get your footage to look reasonably good or behave correctly in Premiere’s Lumetri color panel?
I have something for you. It’s free. You’re welcome. Download it here, then read about the what’s, how’s, and why’s below.
Video input LUTS that actually work and are accurate
I’m actually a little amazed nobody has seemed to do this before. Of course, everybody has their own way of color grading Canon EOS video footage, but there is much confusion on the internet about how to deal with the video footage in modern NLE video editing suites for one very simple reason: Canon EOS DSLR video footage does not conform to Rec.709.
Yes, it has the same color primaries as Rec.709, but that is it.
There is nothing else about Canon EOS DSLR video footage that looks even remotely close to Rec.709. If anything, it’s awfully close to Canon LOG believe it or not, assuming of course that you’re using the Prolost Flat picture style.
You see, what is going on is Canon EOS DSLR (including EF-M and newer RF mirrorless) cameras actually record video with an OETF of sRGB. Kind of. Sort of. Actually, not really.
It records video using Canon’s in-camera picture styles. These picture styles are designed to render a pleasing jpeg image if viewed with an sRGB monitor. The reality of the matter is the camera is capturing over 12 stops of dynamic range (on newer Canon cameras) and jamming that into something that looks good in sRGB.
This by itself isn’t so much of an issue, the issue is:
- There is more than one picture style
- You can edit the picture styles
- If you make the Prolost Flat picture style you have a lot more dynamic range than Rec.709 can display.
- It’s not Rec.709
So what to do?
This is actually pretty straightforward. Adobe Premiere Pro (and Lumetri by extension) internally are very strict Rec.709 video platforms. They are Rec.709 video through and through, at least as of early 2020. You can’t change it, configure it to something else, or do anything about it. If you want them to work correctly with your video footage, it needs to be Rec.709 video footage.
Plain and Simple.
So, do a little testing, characterize the dynamic range of Prolost Flat and work out what actual RGB video code values map to scene referred linear light, then takes those code values and map them to appropriate Rec.709 values in a tidy little LUT .cube file.
What do you get?
The zip file contains two .cube files. They are both technical input LUTS designed to be used as input LUTS in the Lumetri Color panel in Adobe Premiere Pro. They are named and labeled to make them easy to tell apart.
The first LUT is a full range LUT. I recommend this LUT to be used most of the time because it linearizes the full range of what the camera can capture in Prolost Flat so that the rest of the Lumetri Color controls after it actually work correctly, and you therefore have the most flexibility in dealing with your video footage. This LUT makes Rec.709 video code values all the way up to 120 IRE (because that is what the camera is actually capturing in dynamic range) on the top end and does not dip below 0 IRE on the bottom end. How to actually deal with this much dynamic range during the video color grading process is a subject for another blog post, however, this LUT gives you as much in-camera video capture and post processing flexibility as what is afforded by using Prolost Flat as a picture style. You can expose in-camera however you want, confidently knowing that the Lumetri Color controls will work the way you expect them to once you apply the input LUT.
The second LUT is almost exactly the same as the first LUT, but has one change. It keeps the video code values in the Rec.709 broadcast safe legal range. If you use this LUT, you should take great care to expose correctly in-camera. This LUT introduces a knee in the highlights to roll off the upper highlights and specular highlights so that no matter what you do in-camera, you will never exceed Rec.709 broadcast levels in Lumetri after this LUT is applied. If you’re shooting in a studio with very controlled lighting and you’re not really going to get nutty with the color grade in post processing, this LUT is a very simple and fast way to make Rec.709 compliant footage that looks really good.
Caveats
Using these LUTS may not look very good unless you’re actually looking at your video footage on a Rec.709 display. If you look at it on an sRGB display, it won’t look the same. Again, this is for making in-camera footage Rec.709 compliant so that Adobe Premiere Pro and Lumetri Color will work the way they’re supposed to. You still have to conform your video footage to whatever your output is, be it Youtube, Netflix, Vimeo, or actual network broadcast TV.
These LUTS are standard .cube files, and therefore will probably work just fine with other color grading suites like DaVinci Resolve to conform your Canon EOS video footage into something that those suites can then work with as well. I don’t use those other suites, so do this at your own risk if you do use something other than Adobe Premiere Pro.
These LUTS make the assumption that you’ve actually correctly set your Canon EOS DSLR or Mirrorless (RF or EF-M) camera up with a correct and proper Prolost Flat picture style. While other camera manufacturers (Nikon, Sony, Fuji, Panasonic, etc.) have in-camera neutral picture styles that you can modify in a similar way to Prolost Flat, they are not the same and should not be used with these LUTS. Those cameras should have their own LUTS made for those specific camera picture styles.
Conclusion
If there is enough interest, I can probably make a few posts or videos with how to deal with the post-LUT footage in Lumetri along with some best practices that I’ve come up with over the years.
Enjoy!
OK, we’re going to get nerdy here. There are many different kinds of artificial lights, and then there is the light from our sun, commonly referred to daylight. If you want to read up on light color temperature, Wikipedia has a great article.
For artificial lights, they generally fall into a couple of different classes: warm, neutral, and cool.
Warm lights are lights that are tungsten, incandescent, candles, etc. Neutral lights are what you generally see in most retail stores, and nowadays usually consists of fluorescent or LED lighting. Neutral light usually sits between 3800K and 5000K. Cool lights are generally any light that has a color temperature above 5000K.
For photography, if you’re shooting ambient light, it’s going to be all over the place. If you’re shooting with continuous “Hot Lights” then it’s generally on the warmer side (2800-3200K), and if you’re shooting with the newer LEDs, the good ones are tunable, but otherwise they’ll be on the cooler side, and if you’re shooting with a speed light or studio strobe, it most definitely will be on the cooler side, usually at least 5500K, but sometimes upwards of 6500K depending on the design of the light’s electronics, quality, and power setting.
This all leads to an interesting question: When shooting people, is there a best color temperature to use that renders more pleasing skin tones? Searching Google leads to lots of articles on how to light for skin tones, but very little in the way of whether to use warmer or cooler color temps for your lighting. With that being said, generally, pros tend to err towards warmer color temperatures (i.e. Tungsten) because it tends to look better. This is why much of our indoor lighting for houses is generally pretty warm.
I thought I would put this to the test and take some pictures using a studio strobe at it’s native color temperature, which is advertised to be ~5600K, and then that same strobe, but gelled with a CTO gel to get the color temperature down to roughly what a tungsten hot light would be, which is ~3200K, then compare the two and see what it looks like. Note: the color temperature is going to vary a little depending on the power level of the strobe, but it should be roughly correct.
So lets start with a standard bare strobe with no color correction:
Here’s the color checker chart:
So we can see we’re correctly white balanced for the light in our software, now lets see what yours truly looks like under the exact same light with the exact same white balance in software:
I look like a caucasian guy. If anything, my skin is rendering a bit on the flat or gray side partially because I’m one of those people that has a neutral skin undertone. I am however cursed with a pretty bad complexion, so there are parts of my face that are rendering as blotches of color.
Let’s look at the same light, but gelled to 3200K:
Again, we can see that we are correctly white balanced in our software. Let’s see what I look like under this same light:
Hmm… that’s interesting.
Let’s look at the two color checker cards side by side. The one on the left is 5600K the one on the right is 3200K:
We can see that even though the the white balance between the two matches, the colors don’t exactly render the same way.
Let’s look at me side by side, again left is 5600K, right is 3200K:
Again, very interesting. Keep in mind some of the color you’re seeing on my face is due to my less than ideal complexion, which some people may have, so that’s something to watch out for.
So does the color temperature of your light effect the skin tones in photography? I would say yes. Which one looks better? That’s really a subjective thing more than anything else.
The important thing to take away here is that you should be cognizant of the fact that some people might look better in warmer light and some might look better in cooler light and adjust accordingly.
Till next time.
Categories
Blue Hour Hacky Sack
For this post, let’s talk about taking advantage of white balance to enhance your scene.
I’ll start with a mantra: White Light is a Lie. I’m a long time reader of Strobist, and if there’s one thing I’ve learned over the years it’s that white light has its uses, but largely is a subjective creative choice that can be manipulated in the camera, or manipulated with colored gels if shooting with a speed light or studio strobe.
Let’s take the image above. I was recently photographing an event and saw a group of youngsters outside playing hacky sack. It was evening and the sun had already dipped down under the horizon and they were trying to get the last game or two in for the remaining minutes that the light was still there enough to see by. It had been mostly overcast throughout the day and at this point, the sky had light cloud cover.
I took a quick step outside and grabbed a number of frames, the one above being the best one.
Once I got the images pulled into the computer, I initially did a white balance that looked like this:
You can see that it’s evening time, you can see the warm light from inside the building spilling onto the concrete in the foreground, and spilling onto the skin of the people in the frame.
Looking at the Adobe ACR data, the white balance was 8300 Kelvin. Very blue, very cool ambient light. When I did the initial WB, I pulled the reading off the concrete that didn’t have the warm light spilling on it.
On its own, white balanced like this, this could be a totally serviceable image, however, we can enhance the mood and feeling a little bit by adjusting the WB in ACR to something that is a bit more evocative of outdoors during the late evening.
The first modification, I set the WB to Daylight in ACR:
That’s better, and what it’d probably look like if you were shooting daylight balanced film, but not what I was envisioning. The Daylight WB setting in ACR is 5500K.
I then went to Tungsten WB in ACR:
Whoa. That feels like a bit too much blue. The Tungsten WB setting in ACR is 2850K. We need something between daylight WB and Tungsten WB in ACR. Good thing I shot raw.
For those of you who spend any amount of time shooting with flash indoors, you’ll know that many times, you have to CTO your flash to get it match the lighting indoors if you are blending the two. I primarily use Rosco lighting gels, and their range of CTO gels (1/8 to full CTO) with flash results in the following white balances in Kelvin: 4900K, 4500K, 3800K, 3200K, and 2900K.
When I shoot interiors that are lit warmly, I often end up with my white balance set at ~3800K. This still allows me to render the interior lighting to be anywhere’s from roughly neutral to a bit on the warm side (always a good thing if people are in your shots), and since a 1/2 CTO on a speed light or studio strobe lands at 3800K, gives me 3/4 and full CTO if I want to warm my flash, 1/2 CTO if I want it neutral, and 1/4 and 1/8th CTO if I want to cool if off relative to the camera WB. Many interior lights nowadays are generally 4000K to 2800K depending on the type of light.
Being that I was just inside shooting right before this image was taken, and actually had my camera WB set to 3800K, I decided to make my WB center 3800K. It’s right between 5500K and 2850K and falls nicely where a 1/2 CTO gelled flash would be if I wanted to do that, and if I wanted to, I could push my flash into CTB gel territory and match the color of the ambient light outside. That resulted in the image at the top of this page.
So what’s the takeaway? If your camera or post processing software supports it, don’t be afraid to explore the color temperature or white balance of the light in your image to enhance its mood and feel. You’d be amazed at the effect that it can have.
Above is a recent project I worked on that I thought I’d share how it was lit since many people always ask me how I get my photos to look the way they do.
The What
Aside from the color, this photo was actually lit very simply with two lights. Yep, two lights.
Let’s start with the fill light. It was a Paul Buff X-1600 White Lightning studio strobe behind the camera, pointed at a very large, very white wall with an umbrella reflector, so it was blasting light pretty much everywhere.
I gelled it with my stand-by Rosco Calcolor gels: 135 units of Calcolor Cyan, 75 units of Calcolor Blue. I metered it to f/2.8, so that it painted the entire scene with a super deep blue with a slight push to green.
For my key light, it was also a Paul Buff X-1600 White Lightning studio strobe, however, it was placed camera left, and had a standard reflector and 40 degree grid. I gelled it with 90 units of Rosco Calcolor Yellow, and 45 units of Rosco Calcolor Red. I metered it to f/8.0 and placed the light so that it would split the egg in half, one half a nice warm glow, the other half a deep cold blue.
Other technical data: the background is a Savage Thunder Gray seamless paper, the egg is sitting on a studio stool with a black table cloth.
I kept the Lightroom and Photoshop work to a minimum, set the white balance to 5500K, spot healed a few spots of dust/fibers, etc. Very minor tune ups, what you’re seeing in this picture is pretty much straight out of camera.
The How
So how does this work? How do you figure out what strength gels you need where?
Again, this is pretty straightforward if you’re using a calibrated set of gels, which is why I love the Rosco’s Calcolor gel set so much.
So I wanted the overall lighting to push to yellow-orange on the highlight side, and push to blue-green on the shadow or fill side of the egg, both by equal amounts. Since I metered 3 stops between the two halves, all I had to do was figure out my overall proportions, then scale them. For the key side, I kept my scaling at 1.0, which meant my shadow side needed gels with 3 added stops of strength to match.
So, starting on the fill side, I knew I wanted 60 units of blue, multiplied by 3, makes 180 units of blue. In order to reduce how much magenta crossover happens, you need to put a fair amount of green in with the blue, typically half to three quarters. More than that, and it starts to look more cyan than blue. You can totally do that if you want, but for this image, I wanted more blue than cyan, so I went with 135 units of cyan, and 75 units of blue, which gives me a total of 180 units of blue (cyan = green + blue), and 135 units of green. Taking the multiplier into effect, this means 60 units of blue and 45 units of green.
OK, so on the highlight side: The fill touches everything, so just to get back to white, we need 15 units of yellow, and 45 units of red. But we don’t want white, we want yellow to orange, so on top of that, we need to add an additional 60 units of yellow, bringing our key side total to 75 units of yellow, and 45 units of red. This gives us a more green yellow than orange yellow, so we need to add just a touch more of red, say 15 units. This brings our total to 60 units of red, and 75 units of yellow.
And that is what you see in the image above.
Categories
Portrait Lighting Walkthrough
Let’s look at the image above for a minute. Look at the light. Study the complexity of color for a few minutes. What do you notice?
Clearly this image was shot in a studio with strobes, but, would you say it totally looks like it was lit with strobes? Why does it look this way?
Lets break it apart a bit and see how we got here.
We’ll start with a simple truth: White light is a lie. Since when does white light occur in nature? It doesn’t. What we call white isn’t actually all that white, it’s largely just a way for us provide a point of reference to describe other colors of light.
Would you believe me if I told you that the above photo was actually lit with 3 different strobes and they where all different colors of light?
It’s true. Let’s walk through it.
The key light is to camera left. It’s a pretty standard 45 degrees over and 45 degrees up. It’s a Paul Buff X1600 White Lightning strobe in a LumoPro 36 inch Octo-box. Nothing special there. Where it starts to get interesting though is that it is gelled so that the color it emits is red. Specifically, 15 units of Rosco CalColor Red.
Wait. What? Why isn’t everything red then? Well, if that was the only light being used, it would be, however, we’re mixing colors, so lets look at the other two lights.
The primary fill light is another Paul Buff X1600 White Lightning. I’ve put a 180 degree reflector on it and pointed it at the giant white wall behind the camera. I then gelled it with 90 units of CalColor Green, and 60 units of CalColor Blue. This results in a really greenish bluish color if used alone, and because of its position, it basically fills every crack and crevice with this light.
There is a secondary fill light in the form of a LumoPro LP180 speed light pointing at the white wall to the camera’s right and it is gelled with 90 units of CalColor Blue.
Where the magic comes in is how all the lights mix together, because what we’re doing is mixing colors to get a resultant color. Even though all the strobes were metered at different levels, combined with the various gel strengths (this is the reason I use Rosco CalColor gels, they’re calibrated and it’s fairly easy to figure out how much you need for a given light level) in RGB terms, the resulting color is basically 255 red, 170 green, 85 blue. If you plug that into pretty much any RGB color calculator online what you’ll end up with is what looks like about a 1/2 CTO gel.
So why not just do that? Put a 1/2 CTO gel on all the lights. You can, but it wouldn’t look all that interesting.
Why?
This is where the chromatic complexity comes in. Each color is coming from a different angle and hitting the subject at a different angle. Where all three colors are hitting the subject, you get the effect of having a CTO gel, however, in the areas where only two or one of the lights is hitting the subject, the color of the light is dramatically different.
Take a close look at the shadow side of the subject’s face. It is most definitely pushing to blue. It’s subtle, but it’s there. The shadow side is lit so that it’s 3 stops down from the key side, so even though the strength of the gels is pretty high, the effect is actually very subtle.
Now, this is how I think about light and how I light. There are many ways to Rome. You can accomplish something very similar by actually just putting a 1/2 or full CTO on the key light and a full CTB and 1/2 plus green on the fill, and in fact, a lot of very experienced photographers do just that and get more than acceptable results. I prefer the CalColor gels because it allows me to be quite a bit more precise, and that’s just how I roll.
Enjoy!
Kodak has re-released TMAX P3200TMZ film and seeing as I shot the images you’ll probably soon see at various online retailers, I though I’d give a brief walk through of a product shoot lighting setup. It’s not as sexy as shooting people, however, if you do it right, a lot of people see it and steal it.
I keep it extremely simple. It’s really easy to go wrong. The point of most product shoots is to accurately depict the product without anything distracting the viewer from looking at the image of the product.
For this particular shoot, it’s mostly for online catalogs, so the overriding concern is that product be on a white background and not have any weird shadows or reflections happening. Some retailers, like Amazon are pretty specific about what constitutes a valid product shot.
With that in mind, it was shot on Savage Universal super white seamless paper with one light. The light used is a Paul Buff X1600 White Lightning in a LumoPro 36 inch Octo-box placed overhead and slightly behind the subject. The super white paper acts as a light source so you don’t want to get the light too far in front of the subject otherwise the reflected light tends to wash it out a bit.
That’s it! It really is that simple. You can do a similar thing for less cash outlay by using a speedlight in an umbrella placed overhead and replace the seamless white paper for white poster board, but again, the poster board tends to have a more glossy reflective finish, so keep that in mind.
Categories
The Humble Egg
It’s been a while since I’ve shot anything in the studio outside of film profiles, so I thought I’d spend a couple of hours today and shoot a proper fine art/still life in black and white.
This was shot digitally, however, I also went ahead and shot a number of images on Ilford HP5+ 120 roll film.
This is obviously lit, so as a learning exercise, lets walk through the lighting set up.
I used two lights. The first and most important was the base fill light. I took full advantage of the super reflective white wall behind the camera and turned it into a giant fill light by pointing a Paul Buff White Lightning X1600 strobe at it with an umbrella reflector that throws light 180 degrees. This was metered to f/2.0.
With that done, I then took another Paul Buff White Lightning X1600 strobe, mounted a 36 inch Octo-box on it from LumoPro and placed it camera left. I positioned and rotated it until I had the light feathering right across the background and then metered it to f/8.0.
For the composition, I kept it simple. A basic white egg cup, an egg, and a seamless white paper backdrop from Savage Universal.
Once that was done, I shot it at f/16.0 on a tripod with an APS-C camera and a 50mm prime lens. The camera/lens system make is pretty irrelevant as you can do this with pretty much any camera that has a flash hot shoe and interchangeable lens.
If you want to do almost the same thing on the cheap, you can substitute the real studio strobes with smaller and significantly less expensive portable speed-lights. Put the main light behind a nice big photo umbrella, though you’ll still need a white wall. For the seamless backdrop, you can substitute a white poster board for a significant cost savings, however, it tends to have a shinier almost glossy finish than the matte finish of a real backdrop paper from Savage, so keep that in mind. You may need to use a flag (black foam board) to feather the light on the backdrop.
Enjoy!
Categories
The Myth of Film Push Processing
“I shot it at 1600 and pushed it 2 stops! It looks great!”
I’m sure we’ve all heard this. It’s largely a myth. All films are within a third of a stop of the manufacturer’s published ISO rating in most developers.
This is extremely true of C-41 color films because the processing is standardized and the films are manufactured to conform to that processing environment. Given that, we’re not going to talk about color films. If it’s rated for ISO 100, shoot it at 100. If it’s a 400 speed film, shoot it at 400. Any lab that is worth anything can give you a wonderful scan of that film.
For black and white films, this is also largely true based on how the ISO standard prescribes determining the speed of the film which is explained very simply:
Film speeds are based on the exposure required to give a log density of 0.10 above film base plus fog (fb+f).
Keeping it simple
Terminology aside, we can say the speed of the film is determined by the amount of exposure needed to get a certain fixed amount of density above film base plus fog. For the ISO standard, that fixed density is 0.10 log density above film base plus fog. You can use a different fixed density level and you can use a different density scale and that’s totally valid except that it’s not to the ISO standard.
Where the confusion comes in is film density in the shadows or minimum density areas of the emulsion develops at different rates depending on the film developer used. The developer used along with developer temperature and time spent developing affects how much density is developed.
Push that film!
Not so fast. You see, depending on the size of the silver grains in the emulsion, you do in fact need a minimum amount of light to hit each grain so that it will develop anything at all. Believe it or not, that minimum amount of light is amazingly close to the ISO rating of the film.
So what does push processing actually do?
Simply put, push processing develops more density for the silver crystals that did get enough light to develop anything. What this does is make the density difference large enough that you can see it and gives the impression that the film is more sensitive than it actually is. In Adobe Lightroom speak, it’s the equivalent of going into the Develop Module and pulling the shadows up without changing the black level.
It does not make the film more sensitive. Once you go below that minimum exposure level, no amount of processing is going to bring more density into the emulsion. All you’ll do is develop more film fog.
So how come some films still look great pushed?
That’s because normally exposed and developed film typically has its film base plus fog at 6 stops below middle grey. That makes for some awesome blacks. If you switched over to the Exposure Index method of exposing, and under exposed the film by a stop, the film base plus fog effectively moves up by one stop to 5 stops below middle grey. This still results in totally acceptable blacks for most exposures. If you under expose by 2 stops (exposing a 400 speed film at EI 1600) the film base plus fog moves up to 4 stops below middle grey. This results in your blacks starting to look dark grey and a little muddy. This is where the push processing come in. More development time adds more density to what shadows you do have which makes the shadow areas have more contrast which to a degree counteracts the raised film base plus fog. There is a point of diminishing returns because once again, there is a minimum amount of light you need in order to develop anything above film base plus fog.
So that’s it in a nutshell. Pushing film is a myth. If you switch to a different exposure standard (like Exposure Index), then you can get a little more performance out of your film, but at the end of the day, the worst thing you can do is under expose your film.
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