Greg Benz Photography

Cats vs dogs (HDR gain map test)

October 18, 2024

I created this dog / cat test image to experiment a bit on my Instagram account. It’s a gain map which is designed to make it very easy to tell if you are viewing with HDR support. When you view this image and have HDR support, you will see a dog. But if you have an SDR display (or almost no HDR headroom at all), you will see a cat.

This test image is taking advantage of the fact that a “gain map” offers two different views of an image, based on the level of HDR headroom you have. The intent is that you would encode two variations of the same image: a basic SDR which is safe for viewing on any display, and an enhanced HDR which looks much better on displays which supports both HDR and gain maps.

But I’ve hacked the gain map format so that it is rendering two completely different images. If you lack HDR support, you see the base image (the SDR image of a cat). If you have at least 0.5 stops of HDR headroom, then the gain map is applied to generate the alternative version of the image. The intention would normally be to encode HDR content, but I’m not really using HDR pixel values in the dog image. So the effect is that you see one of two regular images, depending on your display’s capabilities.

What are you seeing here?

This image is a JPG gain map.
The base image is an SDR image of a cat.
The alternative image shows a dog. This is encoded for HDR, but I’m not really using HDR values.
So the effect is that you should see one of two different images based on whether your display supports HDR / gain maps (and whether you have more or less than 0.5 stops of HDR headroom, which you can confirm via test #1).
(At the bottom below, I’ve added discussion on some ghosting you may see of the cat. It’s not a real concern, but the extreme nature of my test exposes an edge case.)

I have posted a higher-resolution version of this image on Instagram (IG), where the experience is also a bit different due to how IG uses it.

This simple test can teach us a lot about Instagram (IG), gain maps, and HDR support in general.

First, a few key things to know about gain maps:

If you encode your HDR image properly, everyone gets a great experience every time on any device.
- The intended use is not to share two unrelated images like I am here, but this demonstrates how incredibly flexible gain maps are.
- For a real photo, the worst case is the same result you would have achieved if you did not share HDR – and those with support see a much better image.
- This makes gain maps the key to sharing HDR. Without them, you have no idea what your audience will see, and no ability to ensure a great result everywhere.
The majority of people on IG will be able to see HDR photos properly
- IG is used primarily on phones and most phones less than 4 years old have great HDR support.
Other people will see different versions of your image.
- This has always been the case even with SDR, primarily due to differences in color accuracy, color gamut, display brightness, and ambient light. HDR just introduces some additional variation.
- This is not at all a concern if you are doing #1 correctly (a proper gain map provides a very predictable and consistently excellent result).
- However, if you do not understand gain maps and do not check that the SDR fallback looks as you expect, others may have a poor experience. This is especially true if you simply share an HDR image with no gain map (in which case bad tone mapping is a risk and you have no artistic control over the fallback SDR image).
- This is easy to test by simply viewing your JPG gain map in Safari or Firefox, as neither support HDR gain maps at this time and will simply show the base SDR image.
- I will share more information on this topic in the future through this website and my newsletter in the future to help you get consistently great results. I recommend my tutorial on gain maps as a good starting point.
Your image may be altered anytime you upload to a website.
- Whenever you upload your image, it will almost always be “transcoded” to a new image. For this reason, you ideally should confirm that your HDR image looks like your original when you upload it.
- This transcoding may be done to make the image smaller, lower resolution, cropped, check for hidden malware, etc.
- When the image is transcoded, the result may intentionally or accidentally strip the gain map from your image and result in an SDR-only experience. (It might even be converted to a static HDR as noted below, though this is very unlikely).
- In time, this should happen much less frequently as most of this is simply a lack of support in back end tools for transcoding gain maps. But there are some cases where a service provider may intentionally limit HDR (such as to minimize variability in a mix of SDR and HDR images in a grid).
It is possible for pixels in an HDR image to be darker than in the SDR.
- Some of the dark pixels for the cat become much brighter in order to render the “HDR” dog.
- This isn’t terribly important for most people to know, but I think it nicely demonstrates the incredible power and flexibility of gain maps – even when working with just a pair of 8-bit JPG images.

On Instagram (IG), you may see only a cat, only a dog, or it may change!

Here are some examples of what I see:

On a computer, the image will show as a dog in both the grid and large view, if you are viewing on a browser / display which supports HDR and gain maps.
- No real surprises here, this is how gain maps should work.
- If you are on MacOS, I recommend you consider using Chrome, Brave, Edge, or Opera. Apple has been producing outstanding HDR displays for six years, but unfortunately Safari does not yet support it for HDR photos.
On a phone more than 4 years old (or using an operating system more than 1 year old), you are very likely only going to see the cat (SDR). Again, this is the expected behavior because these old phones simply do not have supporting hardware.
On a Pixel 8 Pro running Android 15:
- The large view shows a dog, indicating HDR is supported (as expected).
- The grid also shows a dog, so the thumbnail is completely consistent with the large view of the image (as expected).
- If I change the phone’s brightness while viewing the large image, it remains a dog (as expected).
On a Samsung S24 running Android 14:
- The experience is surprisingly quite a bit different. I don’t know if this is due to updates in the Android 15 (not yet available for Samsung), Samsung’s unique take on Android (One UI), or possibly something about the hardware (seems unlikely).
- The grid always shows a cat (SDR). This indicates that the small thumbnail generated by IG is SDR only. In other words, it is no longer a gain map.
  - While it would be my preference that all derived versions of my image remain as I created them, I understand how IG may prefer to show a grid where the images appear more uniform by not mixing SDR and HDR content.
  - Future web standards reference a middle ground where HDR may be rendered with partial support. This would offer a compromise so that HDR content shows some of its benefit, without looking so different from SDR content. I imagine that a grid view like this might adopt such an approach in the future (especially as HDR content becomes increasingly common).
- If I change the phone’s brightness while viewing the large image, the live view of the large image shows a cat. This indicates that I am seeing an SDR view of the image while I am actively changing the display brightness. It’s not a big deal, but I would prefer that I get an accurate preview of the display while I’m changing the brightness. Otherwise, the image I see on screen may be significantly brighter after I set brightness.
On an iPhone:
- The experience is different from both Android scenarios above.
- The large view always shows a dog, even when the phone has zero HDR headroom (which would occur when I put the phone in direct sunlight or enable the “reduce white point” setting in iOS).
  - This indicates that my image is not shared as a gain map on iOS. It is not adapting in an optimal way. Instead, the gain map has been converted to a simple HDR image (with no gain map), and some kind of tone mapping is being applied as needed (most likely the tone mapping provided by iOS).
  - I never achieve the full headroom that the iPhone is capable of showing (which is 3 stops when brightness is no more than 80%). I’m getting something close though (between 2 and 2.5 stops of support).
  - In my experience, the results are still extremely good and I have no concerns here.
  - What is likely occurring is that IG uses the Google standard for sharing gain maps and iOS only supports the new ISO standard and Apple’s proprietary encoding). Computer browsers and Android do support that gain map format, but rendering on iOS is probably achieved by deriving a simple HDR.
  - IG has been a leader in HDR and made numerous improvements to HDR support since launch. So assuming my theory that ISO gain map support is key, it is likely that the IG iOS experience will get even better in the future.

Your experience may differ from mine for several reasons including: phone hardware or operating system, the version of the IG app you’re using, the phone’s brightness setting, ambient brightness, split testing on IG (ie, an HDR display may be forced to SDR for testing), etc.

I’d love to hear your experience via the comments below. It would be helpful to know which hardware / operating system you are using, as well as your current level of “HDR headroom” (which you can find on a computer with test #1, or in a mobile phone via the histogram of an HDR photo in Lightroom mobile).

In addition, the image on this page (or IG) can help illustrate a quirk I have seen in numerous implementations of gain map decoders (including several browsers).

Even when you have full HDR support, you may see a bit of a ghosted white outline of the cat eyes and ears or test over the dog.
This helps illustrate that a gain map is not truly 2 photos in the same file. It is a base image (SDR here) and a psuedo image which provides instructions on how to multiply each base pixel to derive the alternate image (HDR here).
The reason for the ghosting here is because you are not viewing the image at 100%. When the image needs to be resized, the base image and gain map should be combined and then rescaled as needed. However, you will likely see ghosting in some viewers because these two “images” are rescaled first and then combined. This causes potential misalignment at edges and/or errors in the gain map math.
If you zoom in or out at the browser level (such as ctrl +/-), you may see the problem get worse or better. If you use the Adobe Gain Map Demo app and set the view to 100%, you’ll notice that the problem goes away.
I consider this a bug, but you are unlikely to see this in a real image. It might occur near high contrast, hard edges – such as a sunset behind a building.
Ideally, the decoders would be fixed to avoid this issue. However, there is a relatively simple fix for any image you share on your website. Just add CSS styling to use “image-rendering: pixelated;“.
To demonstrate this, I have added this CSS to the image here. Just hover over the dog and the ghosting should disappear (as I am applying the fix only while you are hovering for demonstration – you should implement it without the “hover” restriction).
Note that Adobe Camera RAW and Lightroom work well they do NOT exhibit this concern (as the image is rendered to HDR before you might rescale).

Note that if you are looking for an easy way to dive into sharing HDR images / gain maps, I recommend taking a look at the “enhance SDR to HDR” feature in my Web Sharp Pro plugin for Photoshop.

How to show an HDR slideshow on your TV with Keynote

October 16, 2024

If you have MacOS, Keynote, and an HDMI connection to a TV, you can create a slideshow using HDR photos which will play by itself.

Requirements: MacOS Sequoia (ie v15.0 or later) and latest Keynote.

To create the slideshow:

Export images in an HDR format supported by Keynote (HDR JPG / AVIF / JXL from latest Adobe Lightroom Classic / ACR works well).
Make a series of slides with those images.
- Note: the headroom will be limited (not full HDR support) while building the slide. You will only see proper HDR when you play the slideshow (below).
Each image should have an animation.
- Click the image to select it, then near the top right under “animate”, set the preferred “build in” effect.
- Try using “dissolve” to fade in, “fade and scale” to zoom in, or perhaps “blur”.
- Set the duration for about 1.0 seconds.
At the top-right of Keynote, click “document” and set the following:
- presentation type = “self-playing“
- delay = about 3-5 seconds (this is how long each slide/image will be visible)
- builds = 0 seconds (this just adds delay before starting the animation on each slide).
- enable “loop slideshow” if preferred.
Go to the “Play” menu and make sure “in fullscreen” is checked.
Click the “Play” button at the top to start (or shortcut key <option><shift><P>)

Please let me know what you think (any other settings you like, etc).

New in Adobe Camera RAW 17: “Adobe Adaptive” profiles, non-destructive Denoise, and generative expand

October 14, 2024

Adobe Camera RAW (ACR) v17 just added some very interesting new AI features:

NEW: “Adobe Adaptive” profiles.
NEW: “Generative Expand“
Updated: AI Denoise, Raw Details, and Super Resolution can all be applied non-destructively on even more RAW files (details below).

These features have the ability to get great results more easily and significantly simplify your workflow. Let’s dive into each of them.

What is the new “Adobe Adaptive” profile and how do I use it?

The various profiles we’ve had in the past (Adobe Standard, Adobe Color, etc) are fixed starting points. The new AI-based “Adobe Adaptive” is meant to provide a better starting point by analyzing the image to generate a custom profile. It’s effect is somewhat like adjusting the sliders for increased shadows and decreased highlights. It compresses the tonal range. The greatest benefit seems to in large areas of shadows (common in landscape) or small areas of nearly blown highlights (such as city lights).

In ACR, just click the profile dropdown and select “Adobe Adaptive (beta)“. That’s really it. You’ll immediately see changes and likely some very impressive results. Any existing sliders or local edits will remain as they were. That’s often fine, but you’ll probably want to make some further tweaks to get the most out of it.

Aside from the profile itself, there is an “amount” slider available when in the adaptive profile. If you drag the amount slider down to 0%, you’ll get the same result as the “Adobe Standard” profile. This lets you easily back off from the AI if it is too much. Often times that is the case (the default can look a bit like the results from older tone mapping software where shadows are too light). Conversely, you can increase the amount up to 200% to really lean into the effect it has on the image.

For more info, see Adobe’s post on adaptive profiles. Note that this profile limits HDR to 2 stops (per Adobe). This can help rein in HDR highlights, and you can always edit brighter from there.

When should you choose Adobe Adaptive?

Without more experience, it’s hard to predict the best uses for such a complex new may be. This will likely appeal to a lot of novice users who are unclear how to get the kind of incredible results which are typically the norm when shooting with a smart phone. If you’ve struggled to get the best results out of your fancy camera, you’ll probably love this new feature.

My experience so far suggests that a wide range of images may benefit even skilled editors. I have seen some great improvements in things like nearly blown highlights which benefit greatly from the new Adaptive profile. It appears to be safe to use on a wide range of images (including those which have already been edited or use HDR). The quality of results will probably surprise many advanced users.

When should you avoid Adobe Adaptive?

As incredible as this new feature is, there are some scenarios where you may wish to skip the adaptive profile or exercise caution:

First, keep in mind this is a beta. There may well be bugs and performance may change over time (ie, re-editing later might produce a different result).
You will not be able to use this feature when working with the Camera RAW filter. At this time, you can only use the adaptive profile when opening RAW images or editing RAW Smart Objects.
There is likely a long learning curve to optimize results. Some types of images or workflows may be optimal with the adaptive profile, while others may be better with the regular profiles.
Do not use the adaptive profile in addition to the “auto” button. ACR will explicitly warn you against this, as the auto feature is not currently optimized to work with adaptive. There will likely be many requests for that, as it would be a very handy combination in the future for those seeking very quick and simple edits.
Those who prefer to work in Lightroom should probably wait, as support is just in ACR for now. You can of course use RAW Smart Objects and view your edited TIF in LR, but you should do the entire edit in PS / ACR if you’re doing to use the adaptive profile.
Be careful if you enable adaptive preset for images you have already edited, as your sliders may need some tweaking with the new profile. That said, I’ve seen some images which benefit nicely.

What is “generative expand” and how do I use it?

Photoshop’s cropping tool has had “generative expand” for a while. It allows you “outcrop” or expand the image area and use AI to create new pixels at the edge. This is great for things like adding more sky when exporting your image for social media. However, this is a destructive workflow. The new pixels will probably be useless if you change the original edit.

With ACR 17, generative expand can now be done directly in the RAW file. This has a couple of important advantages:

Non-destructive. You can make any changes you wish to RAW settings and will not have to recreate the new pixels.
Avoid cropping when making geometry corrections. For example, if you need to tilt or rotate the image to straighten some lines, you may now simply fill in the gaps in the corner rather than cropping out parts of your original image.

To use generative expand:

enable the technology preview. In Photoshop, go to preferences / File Handling / Camera Raw Preferences / Technology Previews, and check the option there.
Go to the crop tab (near the top right). This now includes geometry adjustments (aka “transform” in Lightroom).
Expand the crop and / or make geometry adjustments as desired. If you are cropping, be sure to check “enable expand“.
Click “generative expand“.
Note that the results outside your filled area won’t be optimal, so if you need to further expand later, you will likely need to re-run generative expand.

This is a very exciting feature which targets an important need. However, it is definitely a technology preview and the results are sometimes not great. It seems to work best in areas with simple detail or texture, such as expanding the sky. So be sure to check your results for quality. While it isn’t perfect, it’s an exciting new feature and should continue to improve from a great starting point.

What are the benefits of the new “non-destructive” AI enhancements?

Adobe has generated a lot of buzz around several AI features for RAW images, including:

AI Denoise, which offers incredible improvements on images at any ISO.
“raw details“, which enhances detail within the native resolution of the image.
“super resolution“, which doubles the linear resolution of the image (ie 4x the total pixel count).

What’s new is that you no longer need to generate a new image, and a much wider range of RAW files is supported. You simply enable the feature in ACR and your existing RAW image will be enhanced. This has some important benefits:

Less file clutter, as you aren’t generating a new DNG and no longer need to consider whether you should retain the original RAW (just in case).
You can upgrade existing edits. For example, if you used RAW Smart Objects for your work, you can simply turn on AI Denoise the improve the final result without having to redo the edit.
You can work with many more RAW source files, including: HDR and panorama DNG files, Apple ProRAW DNG, Samsung Galaxy Expert Raw DNG, etc.
- Nearly any RAW file should now work (other than exotic sensors such as Fovean).
- Not currently supported: raster images (such as TIF or any use of ACR as a filter) and Lightroom.

To use this feature, you must enable the technology preview (as as above, go to PS preferences / File Handling / Camera Raw Preferences / Technology Previews).

Conclusions:

The vision for these tools is amazing, and I hope to see ongoing improvement to address a few opportunities (which is to be expected for any “tech preview”).

The overall picture in ACR v17.0 is:

Non-destructive denoise / raw details: Amazing and great to use now. It works like before, but is just much easier and supports more RAW files.
Adaptive profile: Very helpful for some images. Great for enhancing shadow detail, as well as taming some bright highlights. (Be sure to adjust the “amount” slider to optimize results).
The generative expand is on the right track. It can be useful for some social media edits, but needs work to be useful for high quality work such as large prints.

Collectively, these show great vision to bring useful AI capabilities into RAW editing, where they can provide the most benefit by allowing you to work in a fully non-destructive manner. This is a great update, and it will be just as exciting to see these capabilities expand and mature over time.

Is this 1000 nit HDR monitor for $330 too good to be true?

October 7, 2024

HDR monitors tend to cost $1,000 or more, so Xiaomi‘s launch of a 1000-nit HDR monitor for only $330 immediately raises questions. Is this the best value ever offered for an HDR monitor? Is it a piece of junk? Good enough for photographers?

I bought the Xiaomi Mini LED Gaming Monitor G Pro 27i (model P27QBA-RGPGL) and it’s well, pretty interesting. If you’re looking for a low cost way to get into HDR photography, it’s definitely worth a look. It offers a great opportunity to get into HDR on a budget, but with some caveats covered below.

This monitor features:

A very attractive $330 price point
1000 nits mini-LED with 1152 dimming zones (DisplayHDR 1000 certified)
99% DCI-P3
180Hz refresh rate
27″ size with 2K QHD resolution (2560×1440)
included stand supports a wide range of adjustments

Learn more about these terms and how to shop for an HDR monitor here.

HDR specs like these are simply unheard of at this price point. If you only got 1-2 years of service out of it, it would probably pay for itself as price and availability of HDR monitors continues to improve.

How’s the image quality?

The key headline here is the DisplayHDR 1000 certification. The high peak brightness and numerous dimming zones offers a very compelling HDR experience. Actual peak brightness somewhat exceeds the 1000 nits spec. You should be able to achieve 3 – 3.5 stops of HDR headroom in ambient lighting conditions typical for photography work. This is highly capable for a wide range of HDR work.

Equally important is the ability to control black levels to ensure high dynamic range. Haloing is inherent to any mini-LED and this monitor performs quite well. It’s also a bit complicated. It is simultaneously better and worse than the Pro Display XDR (that it can keep up at all with a monitor costing nearly 20x more is incredible). The mixed performance is due to sensitivity around viewing angle. When you look directly at the monitor, haloing is very minimal. However, it is much more pronounced when you view from an angle. So when you are sitting normally in front of the monitor, the Xiaomi offers better blacks than the XDR in the center of the display but clearly inferior blacks near the edges (unless you move your head). It’s not going to win any awards in a star field test. As you get into midtones against HDR highlights, a test pattern such as a +3 stop red over a mid grey will clearly look better on the XDR than the Xiaomi. But when I test real photos (such a sunset behind a building or with detail around a window), I see no isse. There is also some increased variability around the zones, which can manifest as a cursor which appears to flicker a bit if you move it across a black screen. In the rare case where you might want a more accurate look at very dark shadows, you could always move your head to look straight on. Overall, the local dimming is sufficient or very good for almost all practical photography. It exceeds my expectations for this price point and should be very suitable for anyone who doesn’t make a living from photography.

The monitor’s control for local dimming (advanced / local dimming) is unusual. It’s more like a brightness control than something which impacts halos. When set to low, peak brightness measured ~1150 nits. When set to medium (default) or high, it measured ~1310 nits. I would leave it at the default medium value and adjust brightness from display settings in Windows or MacOS (Sequoia has a new slider for 3rd-party monitors). The low setting seems to help somewhat with the highlight rolloff mentioned below, so you could try playing with a combination of the monitor’s dimming controls and the operating system brightness slider if you’re comfortable with these controls.

The monitor spec says it should support 180Hz refresh rates, but I am seeing a maximum of 144Hz on both my Mac and PC. I have never tried using either with a higher refresh rate and I suspect the computers themselves may be the limit here. In either case. photographers need only 60Hz for a decent experience zooming and panning images, and 120Hz is ideal (primarily for smoother text while scrolling). So 144Hz is more than enough, and I’m not convinced that a higher refresh rate would be all that meaningful at 2K resolution anyhow.

What about downsides? This is a budget oriented monitor which offers 2K resolution at 27″. That’s a great option which will meet the needs of many photographers, but it isn’t 4K at 32″. I find it’s more impactful for reading text (compared to my 6k Pro Display XDR, letters clearly are a bit jagged). I used a 2K monitor happily for many years, but I certainly appreciate what I have now.

Highlight details appear slightly clipped / compressed. It would be easy to work around this in editing if it bothers you by thinking of it as slightly less headroom. It’s pretty hard to find examples where this affects the viewing experience in a browser. If you look at the bright right side of the arch in this image, there is some loss of detail. You’d have to be pretty picky to notice / care for the majority of images.

This is also a gaming-oriented monitor. Many products aimed at gamers have rather terrible color accuracy and I was fairly pleased with the results. Neutrals such as the Photoshop UI are visibly shifted red, and warm highlight colors in photographs tend to be somewhat over-saturated. My tests in CalMAN corroberate this (though I’m not sharing detail as I don’t have a spectrometer to properly profile the C6 for this monitor). Gray EOTF tracking is generally a bit dark and shifts notably when the monitor’s local dimming is set to low (as a result, you might lose ~0.5 stops of headroom after boosting brightness in the operating system to compensate and achieve a comfortable level for productivity work). The uncalibrated color is not going do well in numeric tests, but is close enough that a large number of photographers won’t care. If you don’t tend to get deep into calibration, you’ll probably be very happy with the HDR color. That’s important, as there is no standard for ICC profiling HDR at this time and this monitor does not have hardware controls for calibration. At the same time, you can always switch to SDR mode and calibrate that for your print work if needed. Just be aware that HDR will not work while that profile is active, and switching profiles on MacOS is a little cumbersome (you might want to look into using BetterDisplay, which has an option to change color profiles when HDR mode is toggled).

Overall, this isn’t a monitor on par with Apple XDR displays or ASUS (which offers calibration in the hardware), but the fact that I would even use displays which cost 8-18x more than this Xiaomi is a testament to the value it offers. The image quality is surprisingly good and has exceeded my (low) expectations.

How’s the overall product quality?

The monitor and stand both physically feel like a quality product. The on screen menus are easy to navigate. There’s nothing to configure, though I recommend going to System / Backstrip Lighting and turning it off if you don’t like the glow from the back of the monitor.

Inputs are limited to two HDMI 2.0, two DisplayPort 1.4, and a 3.5 mm audio jack. There is no USB / Thunderbolt support, so you won’t have power for a laptop nor the ability to use the monitor as a docking station. And this would imply there’s no way for a user to upgrade firmware (so don’t expect improvements for things like the highlight rolloff I noted above).

I was unable to get audio to work over HDMI nor the 3.5mm jack, but I spent minimal time trying. I assume it is not impressive, as most monitors sound awful.

But I did experience challenges with HDMI. Neither my MacBook Pro nor PC recognized the display as supporting HDR when using an HDMI cable I have successfully used with several other monitors. When I switched to my FIBBR fiber-optic HDMI cable, things went smoothly (I’m a big fan of that cable, but just be aware that it is directional and the side marked “1” must be plugged into the computer to work properly). Refresh rate did not matter (144Hz was fine when HDR was working and dropping to lower settings did not help). Perhaps the HDMI ports on this unit are right at the quality threshold where a better cable is needed. It’s entirely possible my unit performs better or worse than others. As they say, your mileage may vary. DisplayPort (using the included cable) worked flawlessly for me.

I contacted support and found options are a bit mixed. There is no phone support in the US and the Facebook support page uses a bot which was completely unhelpful. However, their email support ([email protected]) was a somewhat more positive experience. I received a very thoughtful reply in less than 24 hours on a weekend. However, things went downhill from there. The support team provided information which seemed inaccurate. They did not seem to understand the difference between technical specs like HDR10 (i.e. information you can use to troubleshoot) and Display HDR 1000 certification (i.e. tests which just prove marketing claims). After repeating the same information three times (I thought I was routed to a bot), they ultimately said the only information the support team has is on their website. I wouldn’t expect any vendor other than Apple probably offers great service for understanding and setting up HDR at this point, you should look for that kind of technical support elsewhere (I’ve tried to share a lot of that setup and troubleshooting information on my HDR page / e-book).

I cannot comment on the long-term quality of this product or how other units might vary. My sense is that you should assume a risk of slightly higher risk of quality issue given this price point, my HDMI experience, and some reports online of quality issues (that said, all monitors run into dead or stuck pixels and people with a bad experience are vastly more likely to report issues than those who have a good experience). I have not seen any such issues and Walmart shows an average 4.7 out of 5 with nearly 1000 ratings submitted. My sense is that this will likely be a popular product that offers a great experience at a unique price point, but I’ve only had one unit for a short period of time.

Should you buy it?

This a product I can recommend for those seeking to get into HDR at a low price point, with the caveat that you may need to try other cables or be ready to return the unit if you have problems. HDR support is excellent, image quality and HDR color should meet most photographer’s expectations, and SDR color accuracy can be improved with profiling if needed (but needs to be toggled off to see HDR, as with any profiling today). It’s also exciting to see budget entries arriving in the HDR space, as this should help make it more accessible to a larger audience.

The only real alternative for quality HDR at minimal cost would be your M1+ Apple MacBook Pro (which has an amazing HDR display but is a 14-16″ display) or to use your TV as a monitor or pick up a used OLED TV. There are many TVs which offer great HDR (especially in darker rooms) and can be calibrated. If you’re willing to spend a bit more and manage the minor downsides of using a 42″ TV as a monitor, the LG C4 OLED is an excellent option.

If you’re willing to spend a good bit more, the ASUS PA32UCX offers 4K resolution and hardware-based calibration. And if you have a ~$2600 budget, I highly recommend the ASUS PS32UCXR.

For more reviews and details on how to evaluate options, see my recommended HDR monitors.

Disclosure: This article contains affiliate links. See my ethics statement for more information. When you purchase through such links, you pay the same price and help support the content on this site.

What do Apple’s latest updates mean for HDR photography?

September 27, 2024

Apple recently release MacOS v15 (“Seqouia“) and iOS / iPadOS v18. There are several key changes which are significantly helpful for HDR photography, including:

support for a critical HDR file standard which should make it much easier to share images
greater support for HDR photos in native Apple apps (including iMessage)
better support for 3rd-party HDR monitors
improved tone mapping to support SDR or less capable HDR displays
support in Keynote (which you can use to create an HDR slideshow)

ISO 21496-1 gain maps:

At WWDC, Apple announced support for developer APIs to read and write gain maps using the upcoming ISO 21496-1 standard. Apple refers to this as “Adaptive HDR“, which is a great term for gain maps as they allow your photo to optimally adapt to any display. This is the key technology for HDR, as it allows us to support both HDR and SDR displays. Everyone gets the best possible image on their screen. And this concept may be used with all important file types (JPG, AVIF, HEIC, JXL, DNG, etc).

There are currently three different implementations of gain maps. The approach used by Google (Android) and Adobe is quite similar to each other, but not identical in practice. Apple’s own encoding is significantly more different, but conceptually similar. Ultimately, the files are not interchangeable and this creates confusing scenarios where HDR support is lost. For example, you can capture and upload gain maps on iPhone or Android to Instagram, so long as you use the same device for both. But you cannot currently upload the iPhone image from an Android and vice versa (thankfully, once you upload it works anywhere HDR is supported). So this mix of gain map formats has slowed adoption as it creates significant cost, complexity, and work for developers. And that’s why the ISO standard is so important.

The ISO 21496-1 standard recently reached the “draft international standard” phase, which should mean that it is close to official approval. It will take a little time before it makes an impact, but should help significant accelerate support for HDR on the web in 2025. Having a single standard will avoid failed uploads and should make it much easier for small developers to add support as standard software libraries add support.

This is a natural starting point, as it’s important to get viewing support before the images are worth creating and sharing (I am unaware of any software which currently supports creating images in the ISO format). So while Apple’s ISO support has no immediate impact today, it is a huge step forward that prepares Apple for the future of HDR but should help generate increased interest in the format.

HDR gain map support in native Apple apps:

Apple is implementing support for the ISO standard in several key areas:

iMessage app.
Photos app
Preview
Quick Look

This includes support for all four apps in MacOS, iOS, and iPadOS. These apps all support the older Apple format, which is still used when capturing HEIC / JPG photos with an iPhone / iPad.

The support in iMessage is particularly important, as you can now simply text your HDR photos to friends and family.

Support for the Adobe / Google gain map spec has not been added. That’s probably not too important, as ISO should quickly become the standard used by everyone. But it does mean that you won’t be able to share your existing HDR iPhone images with a friend using Android, at least not without re-saving the file through software like Lightroom.

Brightness slider for 3rd-party HDR monitors / TVs:

Prior to MacOS 15, you could not control the brightness (SDR white point) of a 3rd-party HDR monitor or TV. Only Apple’s monitors and laptops had this ability. For many people, this meant that their display was often too bright for productivity work like reading email and HDR headroom was limited. This ability to change brightness was the one area where Windows had a clear advantage with its SDR / HDR Content Brightness slider, but that is no longer the case.

MacOS 15 now shows a brightness slider under System Settings / Display for any monitor in HDR mode. It’s incredibly simple, you just slide it to adjust the brightness of the monitor to make it comfortable to view under your ambient lighting conditions. This very simple change has several important benefits:

You can adapt the display to be more comfortable to use and more appropriate for editing prints, without turning off HDR mode. The old default was 203 nits, which is about twice as bright or more than ideal in most rooms without strong window light.
You’ll have more HDR headroom if you are able to dim the display for your room, which will often be the case.
You more effectively use a wide range of HDR monitors and TVs.
- Prior to this update, the only optimal way to view HDR under MacOS was with a 14-16″ laptop screen or Apple’s $5,000+ Pro Display XDR. Those are still best in class displays with many unique benefits, but it meant a loss of HDR headroom when using 27-32″ HDR displays at price points which are affordable to most photographers. That’s no longer a concern.
- This is particularly helpful for working with OLED monitors, which excel in dark ambient light. You can now get incredible HDR results from a 42″ TV that costs only ~$800 or less.
- See recommended HDR monitors list for more info.

With this change, MacOS now clearly offers the best overall HDR experience in terms of both quality and ease of use. Kudos to Apple for opening up their system for better 3rd-party support here, this adds tremendous potential value for a large number of Apple computer users.

Improved global tone mapper:

Gain maps are absolutely offer the best image quality for sharing HDR images. They adapt in an ideal way to any display and leave you as the creator in complete control of the result. By contrast, if you view a simple HDR image without a gain map on an SDR display, it will be automatically adapted using a process known as “tone mapping”. In nearly all cases, a properly encoded gain map will offer more consistently high quality than tone mapping can achieve with an HDR (as it includes input from the artist to create an optimal SDR, allows for local adaptation pixel by pixel, and does not vary from one browser to the next). That said, some images may be shared as a simple HDR due to sub-optimal workflows, automation, or a desire to reduce file size. So you will encounter simple HDR images without a gain map on the web and the quality of tone mapping is still important.

The quality of Apple tone mapping prior to the recent release was, quite frankly, very poor. Highlights often lacked detail and color often looked cartoonish. Thankfully, the latest updates to MacOS, iOS, iPadOS, tvOS, watchOS, and visionOS (including Safari) all include a new global tone mapper which is extremely good. Highlight clipping is reduced and color has been significantly improved. I would still say that the quality of tone mapping in Google Chrome is clearly better, but only by a small margin at this point. Most people would likely say the new Apple tone mapping is clearly much better, but probably would not notice any difference from the results in Chrome without a side by side comparison.

Support in Keynote

If you are updated to Apple Keynote v14.2 and have updated MacOS to Sequoia, you will be able to use HDR photos in your presentations. This may be a very handy way to show HDR photos in a slideshow on your TV.

What’s still missing?

Apple has established an outstanding ecosystem for capturing, editing, and sharing high-quality HDR photos. They have clearly been leading the way for HDR photography along with Adobe and Google. However, HDR photography is still fairly new and there are of course some opportunities for improvement across the ecosystem.

The key gap for Apple is Safari / WebKit, which does not support HDR photos in any format. While you can (and should) use Chrome, Brave, Edge or Opera for a great HDR experience on MacOS – that simply is not an option for mobile devices. On iOS / iPadOS, all browsers (including Chrome, etc) rely on WebKit. As a result, you cannot view HDR photos in a browser on your iPhone or iPad. You can see HDR photos in apps like Instagram or Lightroom, but lack of support for browsing HDR photos at this point is rather shocking. No one has put more energy or cost into creating great HDR displays than Apple, so hopefully we’ll soon get the browser software to properly use the incredible HDR displays they’ve been shipping in phones since late 2020 (iPhone 12).

There are a handful of important but less critical opportunities which remain to be addressed:

No support in tvOS or Airplay2 for sharing HDR photos on an AppleTV.
- This would be incredibly helpful for sharing our HDR photos on the large HDR TV’s most photographers already own.
- There’s no technical limitation here (as far as I can see), as we can already stream DolbyVision movies at 60 frames per second over Airplay, we just don’t have the software to send a still image.
Increased headroom on iPhone.
- The new M4 iPad Pro’s XDR display is 1600 nits and supports up to 4 stops of headroom. Similarly the MacBook Pro’s XDR display is 1600 nits and offers up to 4 stops (5 if you manually set the SDR limit down to 50 nits, though that is not recommended).
- However, there is only support for 3 stops of headroom on iPhone, even though it also has a 1600 nits OLED.
- Below ~80% brightness, the headroom is limited to 3 stops because the peak 1600 nits are not allowed. Ideally, we’d have access to the full brightness until the phone gets to much dimmer values (it probably should be limited near the bottom of the brightness range).
- Aside from any software concerns, competing phone displays have gotten much brighter. The Samsung S24 offers 2,600 nits. This isn’t a huge gain (as 3200 nits would only be one stop brighter than the iPhone), but it is definitely offers a visible improvement in the impact of HDR photos.
No support for HDR gain map thumbnails in Finder (Quick Look / Preview does support). This is just nice to have, as many photographers will likely rely on software such as Lightroom to navigate their images.
No support for profiling HDR displays in order to improve color accuracy
- This is not an Apple-specific issue. There is no ICC standard for HDR profiling, so it isn’t an option on Windows either. If you create a custom profile under MacOS or Windows, you will lose HDR support. Your only option currently is to use a display which is very accurate out of the box, supports calibration in the display (such as an ASUS ProArt or most TVs), or accept limited accuracy / extra steps (you can toggle to SDR mode for an accurate display for printing)
- Apple displays are so good that it’s quite optional, but that’s not the case for many 3rd-party displays – and many photographers have very high standards for accuracy.