HDR Bit Depth with Strobes
Alright, so let's look at some numbers. Which I don't, I'm terrible at math and I don't really care about numbers so much, but let's put things in perspective a little bit. So your eight bit jpeg only has 256 colors per channel represented in that file. So if you've ever gone to a jpeg and you go, and you say you process it as a psd in Photoshop and then later you want to go and ya, oh it's a little to dark or I don't have enough shadow detail and you wanna go pull it out of the jpeg, it ain't there folks. It ain't there. It gets you noise. It really beats it up fast. So you never, ever, ever wanna make adjustments on a jpeg. Never. So if the client says, that's a little too dark, and you sent over jpeg, you go back to your original, hopefully you still have it, and you make your adjustment. If they want a jpeg, then sent 'em back another jpeg. Because there's not much value there. There's not much tones. And we're looking on mon, see here's the problem. We live in a digital age and we...
're used to looking on our iPhones, iPads, and our computers. We look at images that way. And so, an eight bit with 256 colors looks okay, I say looks, we've accepted it. As it being okay. Oh yeah, yeah look at a jpeg. That's fine. 256 colors. You make a print though, you want more information. Right? And so, we've kinda gotten, let me give you a little analogy. So when I was starting out in photography Kodachrome was the ultimate color transparency film on the market. Ektachrome which was E-6 process, that meant you could have it, most labs had an E-6 processor. Kodachrome you had to ship it to Kodak. It was a much more complicated process. But Kodachrome was a beautiful film. It gave you gorgeous reds and greens. Terrible blues. Ektachrome gave you really nice blues but not very good reds and greens. And so, as a photographer, I wanted the best slide film when I was shooting for my clients. And I got used to shooting Kodachrome. My clients got used to using Kodachrome. And so, I would go out and I would shoot projects and I come back and I'd hand them this transparencies. And they'd look and go, oh man this is great. Thank you Joel. And then eventually, so Kodachrome gave you kind of a muddy, gray skies. It would be blue out, but it was kind of a muddy gray. A little bit of blue, but not much. We got used to that. Art directors got used to it. Everyone got used to it. Then Fuji came out with Velvia. This film that was like gorgeous. It had a good balance between all the reds, greens, and blues. The first job I did, I went out and photographed this project, came back with Velvia and I was like, Wow! And I laid it on the light box and the first thing the art director said was, Oh, my goodness. What did you do to the blues? They are too oversaturated. (audience laughs) Because we got used to gray, muddy, blue skies with Kodachrome. So my point is this, is that we have been, we got used to the monitor standard. Which is eight bit, 256 colors represented in our images. And now, we're just kinda used to that. Oh yeah, it's fine, eight bits' fine. Well it's not. We've got more information there that we're throwing away and we need to learn how to utilize that information. So the first camera that I used was a 12 bit camera, that's 4 thousand roughly colors per channel. A 14 bit, now we have 16 thousand colors per channel. So that's gonna be times three. But represented in 14 bit. So look at 16 bit. Now we've got 65 thousand colors. That's a pretty good jump. But look at 32 bit. That's four billion plus values, tones, information in a file. Look at the jump. So here's what I do. You take a piece of paper like a piece of copy paper, throw it on the ground. And let's say that represents the heighth of eight bits, so 256 colors. So, if I stack up a bunch of, let's say paper comes in 500 blocks of 500. You go to the Office Max or whatever. If I do 14 bit, you know I'll have a stack of paper like this. Pretty good chunk of paper. 16 bits gonna be up here somewhere. Do you know what 32 bit looks like? Stacked paper. Over a mile in the stratosphere. It might be actually a couple miles. It's like way up there. Stacks of paper. That's how much information you get in a 32 bit file. Now, do our monitors see it? Nope. Does my eye see it? Probably not. So why even go to the trouble of getting a 32 bit file. It's because I'm gonna now go beat it up. So, if you have a bucket, let's say a five gallon bucket of marbles that represent all your colors, your values. So I have an eight bit, five gallons bucket. I used to paint houses, so that's about that tall. And I've got all my marbles in there. So let's say I go and I want to, I have an eight bit file and I want to adjust the levels. So you go into Photoshop and you adjust the levels. You know what I'm doing? I'm just taking scoops of marbles and I'm throwing them out of the bucket. So then you end up with a six bit file. That make sense? So let's say I have two buckets of marbles that represent 32 bit. I mean, say 16 bit. And I know I'm gonna send it to my client, it's gonna be eight bit. So I start doing levels and doing all this stuff and I'm scooping marbles out. And I end up with about a 12 bit file and I send him an eight bit file. What do they get? A true eight bit file. So the more the marbles you start with, the more you can beat it up and then give the client a file that's still pretty clean. So if I want to end up with a 16 bit file, true 16 bit file, I wanna start above the 16 bit and beat it up. Does that make sense? That's why I wanna get 32 bit. Or at least what we would call 32 bit. And I say that only because we are at the mercy of Adobe or another company that builds a program that works in creating a 32 bit file. We're at the mercy of, truly are they giving us a 32 bit file? I've talked to the Adobe people and it's complicated. Meaning that when Adobe goes in and creates software that works in 32 bit, they have to do some shortcuts. Because a 32 bit file is like a lot of paper to move around. And so they're doing some shortcuts. But ultimately they're giving us a file that we can say 32 bit, but is also a lot more than 16 bit. Does that make sense? So, I'm pretty confident that when I work in a 32 bit environment, I'm getting a lot of information. A lot more than I would ever get in 16 bit and so therefore I can do some damage to it. Does that make sense? Alright so look at the numbers here when I do the math, so that's your four billion times this equation, which I don't even know what that is. It comes out to 79 octillion. I didn't even know that existed. Octillion. That's a lot. And so let's look at what it is in the shadows. Now this is the truth of where 32 bit comes in. So if you have an eight bit file, your jpeg only has four bits of information represented in that shadow. That shadow detail. That last little section of your image before it goes to pure black, where you have detail. So detail on a black shirt or whatever it is. You only have four bits of information represented in that jpeg. That's nothing. So look at a 14 bit capture. That's what we do in our cameras. We only have 256 colors represented in the shadows. 16 bits, over a thousand. But look what 32 bit gives me in the shadows. Right there you should be a believer. Right? You a believer? Amen? Come on. That's where it is. And that's where your gonna see the most drastic advance in your images, is in the shadow detail. Now we have a lot of detail in the highlights. I didn't put this in the slide, but if you, and I'm terrible at math, so. I'm gonna explain this as easy I can. When you have your bit depth, as it falls into an image. Bit depth falls primarily in the highlights and works it way down. So if you have a thousand bit depth, 500 bit depth falls in your top highlight, where the skin is just about to blow out. That's where most of your bit depth falls. Then half of that goes in the zone next to it. So if you have, like Ansel Adams used to say, there's 10 zones, as you go down to black as you fall down to with, each zone you go down you only get half of what's remaining of the bit depth above. So it's thousand, 500, 250, and it works it's way down. That's why your shadows don't have much bit depth. 'Cause your working your way down. And so, with 32 bit, I'm guaranteeing myself that I have all this gorgeous shadow detail that I can pull out. And that's where you see your most drastic change from going from a normal 14 bit one capture to a HDR 32 bit captured. Or even a 16 bit captured image. Dost that make sense? Shadow detail is important. So I say the proof's in the pudding. And so when I create images of like this Italian opera house with this actor and he's not shot 32 bit, but the background is. And I get all this incredible detail in things that I would not normally get. And so I always love to do images that just go and make your jaw hit the floor. And again, we're on a eight bit monitor here. And you know jpeg as I'm showing you here. But if you saw a print, you'd go, oh my goodness. Right? The details there. So this girl we shot last summer. 32 bit. HDR. Strobed. Out in the field. Pop, pop, pop. Three clicks. And the funny thing was, is this is cropped in. But the funny thing was is in a 14 bit, you had the water kinda reflections, but when in 32 bit, you could see right through, all of the water onto the bottom of the lake. It just was incredible how much detail I had.
Jane Ames had asked, "Okay, so just to be sure, "do you set your camera up differently "for different bit files? "Or is it just something that's there."
Alright, so in the camera right now, most cameras can capture HDR to give you three files. There's some cameras that will, and my camera will do it too, that'll capture an HDR and actually blend it in the camera but it ends up as a jpeg. So it's really not a true HDR. The only reason I would use that is if I'm shooting an architectural shoot of a client and I'm doing all these buildings. And so to give them like a proof sheet of everything that I'm doing, I can capture HDR in my camera, that blends three together to make one jpeg and then it also saves the three raws and then when I send them over the proofs, the jpeg proofs, it's a blended HDR of everything. It's not a very, it's good, but it's not like it's a final HDR. But it's a good representation of what I was doing. So instead of having me to process every single HDR to give them a look at what I was doing, I can do it in camera. So that's the only time I'd ever us that. But the question was CamRanger is going to take over my camera and create an HDR bracketing ISO. So the only way I'm gonna use strobes is with an ISO bracket. That's the only way. So the CamRanger, which I'll show in a minute, will actually take over your camera.
So one more from our friend Jessica Lark, who's tuning in, who says, "Does the lighting that you use "affect the way that you shot HDR, if you're using "artificial strobes, sun, does that change the way you shoot?"
Okay, so let's go back to this. If I'm using a continuous light, like a, we used to call them hot lights, but a big hot light like this or a diffused light. Then I can shoot the regular shutter speed bracket. But when it comes to strobes, I have the use ISO and no I don't change my lighting up. I'm just now gonna get a image that has a lighter exposure, a normal exposure, and a dark exposure to give me a range that gives me 32 bit. So I don't change my lighting up necessarily, any. I don't do anything different.
So if it's a different type of lighting, you don't do anything different or we talking just strobe --
Yeah, so in strobe it has to go with the bracketed ISO. If I'm gonna do a regular portrait that is without stobes, I can go shutter speed. But let me give you one little tip, that's really amazing. Is that when I go back, I can't go back here. I probably could, but let's see if I can go back. Alright here it is. This image is shot on loca, obviously on location, at Lake Tahoe. And I could have bracketed my shutter speed here, the standard way we do our cameras. But I chose to bracket ISO here. Because when you do a time exposure of water, if you have three different time exposures, the water gives you three different movement looks. And when Photoshop or any program starts to put those together, it doesn't like it. 'cause you got a really soft one, you got one that's kinda semisoft, and then one that's got, the water's kinda frozen. 'Cause you got maybe a two second, let's say it's two second, eight second, 30 sec, whatever it comes out to, bracketed. So what I discovered is, I set my camera to go 30 second exposures and my time stays the same, I only bracket my ISO. 50, 160, 500 whatever it is. And now I get a smooth, smooth, smooth a water transition, same looking water transition on all three images. And Photoshop loves it. (snapping fingers) Just like that it just puts it together. Where the old way, with clouds moving a little bit or something moving, I would get three different movements and it didn't like it. So, now whenever I'm shooting water or clouds moving I bracket my ISO to give me the same movement on each picture.