Many internet pundits and brand advocates tout Dynamic Range as a super important thing while seeming to barely understand it. Even major publications have no clue what Dynamic Range is, what creates it, or why it matters. If you’re confused about the truth behind Dynamic Range, you’re not alone, many people are confused about it because there’s more wrong information out there than correct information.
Dynamic range is the difference between white and black in an image. The tricky part comes in when defining what black is and what white is. Black is a little bit easier because black in an image simply means there’s no light coming from that part of the image. White is more difficult though because white has no limit technically speaking. White can be as bright as the sun on a clear summers day, or it could be as dim as a candle flame in a dark room. It could be as bright as ten thousand suns exploding simultaneously.
Basically DR (Dynamic Range) doesn’t relate to any absolute light value. Simply put, DR is any difference between dark and light areas in an image. If an image has a really strong light source it will probably have high dynamic range because of the hard highlights and deep shadows. A high dynamic range scene is almost always going to involve direct light such as sunlight or some other powerful light source. This is extremely important to fully understand because if you can control the light, you can control the DR of the scene.
DR relates to light, so if I take an image with my strobes set to high power, and my highlights are blown out, should I run out and buy a new camera? Or is turning down the power on the strobes a better idea? Remember, white is relative, the light source doesn’t define brighter highlights, the exposure controls that. If the balance between highlights and shadows looks bad, it’s really a lighting problem not a camera problem.
Some people are going to argue that fact but if you actually work with lighting you’ll soon realize that it doesn’t really matter if a camera has 12 stops of DR or 15 stops of DR because it’s just as easy to screw up the light with either. DR is nice to have because it does give a buffer for mistakes or editing changes, but it doesn’t usually change how the image is going to look in a properly lit scene.
Speaking of not changing the image, here is a little known fact: too much DR can lower the quality of the image. One major misconception is that .jpg can only handle about 8-9 stops of DR. This is essentially wrong. DR has nothing to do with file formats or bit depths. What happens with .jpg is this: the file converter (Photoshop) throws out the highlight information so that it can apply more grey levels to the mid-tones which are the most important part of the image visually. If Photoshop didn’t do this it would be putting details into areas of the image that don’t matter and it might cause banding or other artifacts to become more obvious in the mid-tones because of the limited amount of grey levels in an 8-bit .jpg.
If for instance you wanted to be stubborn and try to smash 16 stops of DR into a JPG, most likely this will end up messed up looking because the highlights and shadows will receive way more details (grey levels) than are really visible and will cause the mid-tones to look like they’re 5 or 6-bits rather than the full 8-bits of a .jpg file.
Many people now argue that we should shoot in RAW format to retain highlights and shadows. It’s true, RAW format has more grey levels so it can safely store more highlight and shadow information without negatively impacting the mid-tones. However, this isn’t exactly how this problem is typically solved. Usually changing the lighting to be more pleasing is better than relying on camera data to edit the image after the fact. No matter how good your camera is, correct exposures will beat edited exposures, its just the basic fact of how this stuff works. If a photographer has the time to make the changes they can probably devise a better lighting situation, but if they’re working on site with a live subject like at a wedding, changing the lighting might be impossible.
Having said that, most photographs (by amateurs) are not taken in studio settings, they’re taken outdoors in sunlight which is much more difficult to control. There are ways to minimize sunlight but not everyone wants to go through the trouble. Many people will simply want to point the camera and take the picture regardless of the lighting situation. It’s fine, maybe you’re one of those people who wants their camera to solve all their problems and I get that. It’s the 2023 way of doing things. But there aren’t many cameras that are going to let you take perfect pictures in every possible lighting situation, eventually you’ll have to make some kind of compromise to get the highest quality image. You’ll have to choose to blow out the sun, oh no! The sun looks white to our eyes, we can’t directly observe the sun so if the sun isn’t blown out it will look weird.
Now I’m really going to fire a shot across the bow of the DR enthusiasts. HDR content. HDR display does not equate to DR in a camera. HDR content works off the brightness in the image, but if the white’s aren’t true white, then the brightness effect of the HDR TV won’t be as bright as it could be. TV’s don’t know what the absolute brightness is, they have to work off the pixel color. So HDR display has nothing to do at all with high DR camera’s. Nothing except that too high dynamic range in camera will actually lower the HDR effect on the TV. People want high contrast lighting, bright white highlights, and inky black shadows. That can be done with most good quality digital cameras. These crazy 16-17 stop cameras are mostly unnecessary for accomplishing the high contrast HDR look that is currently popular.
I’ve been watching streaming content on a large 4k TV and I find that it is often almost a little disturbing how realistic and large the people are on screen. It almost looks less real than less resolution looks. Because it isn’t what we see. We’re not used to seeing the pores on someone’s face. These TV’s are so sharp, whenever a closeup comes on screen it’s like a shock to my eyeballs. There’s so. much. detail. It’s not an argument against more dynamic range per-se but it is in argument in favor of not worrying about the dynamic range of your camera too much. If streaming looks this good then I doubt that buying a hugely expensive camera for the dynamic range is going to make a major difference in the quality of most people’s work.
Aside from TV’s being mostly streaming based, another quality hit is coming from Google and Apple. They’re pushing new compression standards for images that are even more compressed than typical .jpg images. They basically want every image on the internet to be 10 k-bits or less. Again, tons of information in the images is being thrown out whether it be streaming compression or internet image compression, all that extra dynamic range barely exists for the end user.
Does all this mean that I don’t want a camera with 18 stops of dynamic range? Heck no! Of course I want that. But being completely honest… I wouldn’t want that all the time. I’d actually like a camera that could choose how many stops were necessary for a given image, or one that I could set that value myself. I wouldn’t want to dumbly take 18 stop images with 16 bit RAW files when it’s not necessary.
And be realistic about what generating that much visual data means. It means that 8-bit .jpg won’t cut the mustard anymore and consequences for that ripple throughout the space time continuum. It’s hard to even quantify the many hundreds of billions of dollars that it would take for the world to fully adapt to that much visual data being transmitted here and there and everywhere. 99.9999999% of people would have to upgrade their TV’s, their phones, their monitors, their internet connections, all just to see 18 stops of dynamic range on their TV’s, which would be blindingly bright by the way since the sun is blindingly bright in real life.
And forget about Blu-Ray, it would take technology at least an order of magnitude better than Blu-Ray to handle all that visual data. Remember that Blu-Ray discs only store data as 8-bits per channel. Even going to 10-bits would make Blu-Ray obsolete.
Of course we can always dream up “reasons” for certain things like having 18 stops of dynamic range. Of course! But as of right now it remains a corner case that only the best photographers in the world need to worry about.