But what are the advantages of recording at the highest sample rate and bit depth possible? One obvious advantage is that your digital recording captures almost the entire analog sound perfectly.
A higher bit depth and sample rate during recording will provide a more accurate representation of the analog signal in digital domain. Going at the low end, selecting 8- bit depth and 44.1 kHz (or even lower) does not do any good.
Professional music production has its best practices in sample rate and bit depth. The most common bit depth and sample rate used in commercial audio and broadcasting is 16- bit /44.1Khz (this is the sample rate of CD audio, commercial MP3, etc that you found in recording stores, streamed in Internet radio, everywhere).
If our scale is brightness from pure black to pure white, then the 4 values we get from a 2- bit number would include: black, dark midtones, light midtones, and white. But if we have enough bits, we have enough gray values to make what appears to be a perfectly smooth gradient from black to white.
Here’s an example comparing a black to white gradient at different bit depths. It would be convenient if all bit -depths” could be compared directly, but there are some variations in terminology that are helpful to understand.
Photography software (such as Photoshop and Lightroom) refer to the number of bits per channel. Which means that an 8- bit RGB image in Photoshop will have a total of 24-bits per pixel (8 for red, 8 for green, and 8 for blue).
For one, it would be a lot of work to develop both Photoshop and file formats to support other bit depths. But most importantly, there are huge benefits to using a file format with a few extra bits (as we’ll discuss later).
Monitor vendors want to make their equipment sound sexy, so they typically refer to displays with 8-bits/channel as “24- bit (because you have 3 channels with 8-bits each, which can be used to create roughly 16MM colors). In other words, “24-bits” (aka “True Color”) for a monitor isn’t super impressive, it actually means the same thing as 8-bits for Photoshop.
A better option would be “30-48 bits” (aka “Deep Color”), which is 10-16 bits/channel -with anything over 10 bits/channel being overkill for display in my opinion. With a clean gradient (i.e., worst case conditions), I can personally detect banding in a 9- bit gradient (which is 2,048 shades of gray) on both my 2018 MacBook Pro Retina display and my 10- bit Enzo monitor.
And even when I am looking for it, I cannot easily tell exactly where the edges are in comparison to a 10- bit gradient. An 8- bit gradient is relatively easy to see when looking for it, though I might still potentially miss it if I weren’t paying attention.
I created a software algorithm to generate my gradients in every bit depth from 1 to 14 on the image. Instead, I’ve posted a full-resolution JPEG2000 image (i.e. 16- bit ; I do not see any differences between it and the original detail, even when processing it with extreme curves).
It is also important to note that you are likely to run into false “banding” when viewing images at less than 67% zoom. See this article I wrote on false banding to learn how to avoid any confusion.
If we never edited photos, there would be no need to add any more bits than the human eye can see. If we significantly brighten the shadows or darken the highlights, then we are expanding some portion of the range.
A typical real-world example would be various “bands” showing up in the clear blue sky or excess noise. As you apply Curves or other adjustments, you are expanding the tonal range of various parts of the image.
So I’d suggest an extra 4-5 bits over the limits of visible banding to be safe. If you process for fine art black and white, then these numbers apply directly to you.
You can remove banding in post-processing using a combination of Gaussian blur and/or adding noise. Taking all of this into consideration, 12-bits sounds like a very reasonable level of detail that should allow for significant post-processing.
The result is that the bits used for shadows are lower quality (see this Preview article for an in- depth discussion of the topic). So there may be value in capturing extra bits of detail depending on your needs and camera.
To test the limits for my Nikon D850, I shot a series of exposures bracketed at 1 stop intervals using both 12 and 14- bit RAW capture with my D850 at base ISO under controlled lighting. My test scene included a gray card to help precisely evaluate white balance.
I then processed the images in Lightroom (LR) using exposure and white balance adjustments. The color cast starts at about 3 stops of underexposure (-3ev), is much more apparent at -4ev, and is a serious issue at -5 and -6.
So I set both to +4 exposure and then adjusted the RAW curve to bring in the white point to 50%. What I found surprised me, the Capture One (CO) results fell off much more quickly with deep shadows.
This gives me more latitude to deal with extreme scenes or work with files that I may accidentally underexpose. Clearly, this is massively underexposed throughout the image and about as extreme an example as you could ever imagine.
Because Lightroom only allows +5 stops of exposure, I also adjusted the curve to bring in the top-right point to 80% for the both of the versions below. Lightroom was unable to get a proper white balance from the gray card, there is simply too much color noise at the pixel level in this file.
The final image shows a residual color cast and greater contrast (with the shadow behind the towel being most notable). Much more concerning though is the splotchy color noise (which you can see in the lighter part of the towel shadow below).
Also, tweaking the white balance just slightly more than I have here started to show some large gray splotches in the wood of the door. So there is an advantage to shooting with a 14- bit file on the Nikon D850, but it is relatively slight under extreme conditions.
If you want the absolute best quality in the shadows, shoot 14+ bit RAW files (ideally with lossless compression to save space). This is the best choice if you don’t care about larger files and shoot scenes with wide dynamic range (deep shadows).
Worth testing your camera to see if you can use a lesser setting to save on file size. That holds true even if you are using an 8- bit source file (such as a stock image downloaded in JPG).
Even if the source has been degraded, processing in 16-bits will still yield better results as it will minimize the compounding of rounding errors in the math with multiple adjustments. The benefits of 16-bits are largely in the ability to manipulate the image without causing issues.
Conversion of the final edited image to 8-bits is perfectly fine and has the advantage of creating much smaller files on the Internet for faster uploads/downloads. Go to Edit / Color Settings and make sure “Use dither (8- bit /channel images)” is checked.
If you are using Lightroom to export to JPG, dithering is used automatically (you don’t have a choice). This helps add a bit of noise that should minimize the risk of any banding being exposed with the final conversion to 8-bits.
If you print at home, you can just create a copy of your 16- bit working file and finalize it (flatten, sharpen, change color space if needed, etc). However, if the vendor requires a JPG or you want to send a smaller file, you might be faced with questions about converting to 8-bits.
I have printed hundreds of very high-quality images that were uploaded to my vendor as 8- bit JPGs and the final images look amazing (exported from Lightroom with 90% quality and Adobe RGB color space). However, you can help guard against potential issues by ensuring that Photoshop is using dithering for the conversion to 8-bits (see previous section).
Color Space determines the maximum values or range (commonly known as “gamut”). So you can get larger jumps (risks of banding) by either reducing bit depth or increasing the range over which the bits are applied.
In reality, the longest dimensions of Prophet compared to Adobe RGB aren’t quite double the linear distance in XYZ coordinates. A Ferrari is theoretically faster than a Ford truck, but maybe not on a dirt road.
I have tried various test edits designed to induce banding with Prophet and still not run into it (with 16- bit files). Even using extreme curves and other adjustments that go well beyond how I imagine anyone would edit these photos, I am not able to see any issues.
If you really want to maximize your bits, check out the beta RGB or CIRB v2 profiles (which contain all print/display colors with much less waste than Prophet). A 14+ bit RAW file is a good choice if you want the best possible quality, particularly if you expect you may need to do extreme tonal adjustments (such as increasing shadow exposure by 3-4 stops).
And the larger files may impact your ability to shoot long continuous sequences as the camera’s buffer fills. If you shoot live events, you might be the exception to the rule (to quickly upload and send images).
I’d probably stick with RGB as your camera color space if you do shoot JPG, as your work is probably just going on the web and a smaller gamut reduces risks of banding with 8-bits. Only use 8-bits for your final output to JPG for sharing smaller files on the web (and printing if that’s what your vendor requires/prefers).
Be sure to zoom in to 67% or closer to make sure that any banding you see is not due to the way Photoshop previews layered file. This is a very common issue that causes the photographer to falsely believe there is banding in the image.
Be careful when using HSL in Lightroom and Adobe Camera RAW, as this tool is prone to color banding. If your source file is only available in 8-bits (such as a stock JPG), you should immediately convert the layered working document to 16-bits.
There are massive feature limitations in the 32- bit space, workflow challenges, and the files are twice as big. I would generally recommend merging to HDR in Lightroom instead of using 32- bit Photoshop files.
Keeping in mind that we only need to expand dynamic range a few stops with HDR and that we really only need 12-14 bits in a single RAW file, this is an acceptable format that increases quality without creating enormous files.) If you are one of the few people who need to use an 8- bit workflow for some reason, it is probably best to stick with the RGB color space.
I believe the concerns with Prophet are probably driven by theoretical concerns that not found in the real work, banding caused by use of HSL in RAW (i.e., not related to the color space), false perception of banding when viewing layered files without zooming in, or using Prophet with 8- bit test files (because any loss of quality at 8-bits is a big deal). Others may disagree with me on this, but I have yet to push a file and find banding issues related to Prophet in 16-bits.
When using Photoshop’s gradient tool, checking the “dithering” option creates the perception of 1 extra bit of detail. While some monitors are capable of displaying greater bit depth, the increased file size is probably not worth it.
And while more and more monitors are capable of wider gamuts, not all browsers properly support color management and could display your images incorrectly. The recommended 16-bits for working files should remain sufficient for a few reasons: (1) that’s greater than most monitors and printers are or will be in the foreseeable future and (2) beyond the limits of our ability to see differences.
Aside from P3 monitors, there are printers commercially available which exceed the Adobe RGB gamut as well (particularly in the clans). So both RGB and Adobe RGB already fail to capture the full range of colors that can be recreated on a monitor or printer today.
For that reason, it is worth using a wider gamut now so that your working file can take advantage of better printers and monitors later, such as Prophet RGB. Be sure that you aren’t seeing false banding due to the way Photoshop manages layered files.
But if you do run into banding (most likely if you get an 8- bit stock image), you can take the following steps to minimize it: Use the Smart Filter mask to apply the blurring just where it is needed in the banding.
It is easiest to select the mask, invert it to black, and then paint white where you need the blur. Lastly, add some noise to restore the appearance of grain lost due to blurring.
If you are using Photoshop CC, use the Camera RAW filter to add some noise. About the author : Greg Benz is a photographer based in Minneapolis, Minnesota.