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Canon EOS 5D Mk III & 1D X “Highlight Tone Priority” Aperture Problem and Solution

PhotoJoseph's picture
August 1, 2012 - 3:24am

Thomas Boyd, who of course posts regularly on here, recently brought this to my attention for the Canon EOS 5D Mk III, and then Bob Davis, friend and exceptional photographer, raised the same issue with the new Canon EOS 1D X. We’ve been doing some testing, and have solutions and work-arounds for both existing and future photos made with these cameras.


Photos shot on the Canon 5D Mk III and Canon EOS 1D X that are properly exposed, and look great in the JPEG preview, Photoshop, Lightroom and Photo Mechanic, render at least one full stop darker when decoded by Aperture.


The “Highlight Tone Priority” feature in these cameras appears to be confusing Aperture’s RAW decoder.

Solution for future photos

Disable “Highlight Tone Priority” in the cameras and the RAW files render just fine.

Solution for existing photos

Import into Lightroom (download free 30-day trial version here) and export as 16-bit TIF files, then import those into Aperture.

Long Term Solution

This is an issue that needs to be addressed by Apple.


I can’t pretend to know why this is happening in the first place, except to say that by having “Highlight Tone Priority” enabled in-camera, even though the JPEG preview (or JPEG created in a RAW+JPEG shoot) looks great, as soon as you click on the RAW image in Aperture, you will see it initially looking as expected, then once the RAW file is actually decoded by Aperture, the image will darken noticeably.

The easiest solution moving forward is to simply disable the “Highlight Tone Priority” feature in the camera. Obviously this isn’t 100% ideal, as there are times when you may want this feature to be enabled, but at least there is a workable solution while we wait for Apple to fix this. And the only reason I say this is specifically an Apple issue is because neither Lightroom nor Photoshop nor Photo Mechanic exhibit this behavior.

On the other hand, you may have photos already made that are exhibiting this problem. And if you weren’t aware of the issue, or if you hadn’t compared the Aperture render to the output from another application, you may have found yourself believing that either your camera has a problem, or you do!

Here’s a clear example of the difference. The image on the left was imported into Lightroom, exported as a 16-bit TIF, and reimported into Aperture. The image on the right is the original RAW file, as decoded by Aperture. When that RAW image on the right was first imported, it initially looked just like the one on the left, but then once Aperture rendered the RAW, it darkened as you see here.

Photo © Bob Davis, 2012 (used with permission) — click to open larger
16-bit TIF conversion from Adobe Lightroom on the left; darker original RAW decoded in Aperture on the right

Simply increasing the exposure, or adjusting levels or curves, doesn’t fix it, either. While the overall exposure will probably become acceptable, the shadows tend to lift too much and overall, noise becomes more prevalent. Needless to say, that’s not a Good Thing™.

Apple needs to address this issue, but in the meantime, at least those of you with either of these cameras have a workable solution.

Update on July 31, 2012 - 10:59pm by Joseph @ApertureExpert

According to reader Thomas Emmerich, the Canon EOS T4i / (650D in the US) is exhibiting the same “Highlight Tone Priority” problem.

Anyone else seeing this on other cameras?

Apple Aperture

Same thing is happening with Canon T4i.


Exact same problem with Pentx K5, never happened with K10 or K100. I’ll be looking into the problem within a few days to try and isolate the setting that triggers this behavior. Quite annoying, I must say. I thought of sending my new body back to Pentax but it looks like Aperture might be at fault here.

Exact same problem with Pentax K5, never happened with K10 or K100. I’ll be looking into the problem within a few days to try and isolate the setting that triggers this behavior. Quite annoying, I must say. I thought of sending my new body back to Pentax but it looks like Aperture might be at fault here.

I’m seeing the same symptoms as described in the Problem paragraph above with a T4i. But Highlight Tone Priority is NOT enabled. My sister has same camera with a previous version of Aperture (prior to 3.3x. I don’t know the exact version but she can’t upgrade because she’s still on 10.6.8) without the problem.


Seems like this is occurring with my new 1D-X. Thanks for the short term solution.

I am having the same issue. I am using a Pentax K7, K200 and Kx. All three have the same problem with the RAW files changing to some kind of darkened, white-balanced changed JPG preview after it is selected. Its not acceptable. Editing the shot from there moves it from the JPG preview and NOT the RAW image I need it to. I tried selecting the option in preferences to have Aperture generate the previous AFTER it imports them rather than using the camera’s preview…made no difference.

We need a fix to this asap, Apple.

I have placed a short video of my Aperture doing this as it is “Generating Previews”

See if this is what everyone else is experiencing….

Same problem here, with Nikon D90. Matt’s video clip demonstrates my experience.
Awaiting fix…….

Keith Merrick

I see the same with my canon 7D.

I first noticed a similar problem with my D300 after my upgrade to Aperture 3. Of course this is in conjunction with Apple’s camera RAW upgrade so one can’t be certain where the problem comes from.

My mages end up underexposed by 1/3 to 2/3 of a stop. I can see it happen as I view the thumbnails while Aperture is processing newly imported files. For starters I’m going to double check the D300 settings.


Noticed a similar problem with my D90 a while ago. Most images darker and can’t resolve midtones in some photos compared to Nikon’s ViewNX2. Found that exporting 16 bit tiff’s from NX2 and importing into Aperture helps with most photos but not all.

I have the same issue on a 7D with OS X Moutain Lion and AP 3.3.2

Frederic B

Sorry but this behavior is normal and the same for all Canon bodies (and maybe other brands) when using Highlight Tone Priority : these cameras shoot at one stop below what is indicated and the internal software do the rest preserving highlight tones. There is nothing magical in this function (at least on Canon bodies).
As the jpeg file is a “final” picture produced by the camera with a lot of settings, it looks normal. For Canon bodies, a RAW is a true RAW, not affected by settings like HTP. If processed in DPP, the manufacturer software, the camera settings are taken into account to render the image. It is of course not the case for Aperture which never reads camera settings (and will never read camera settings).
If you think Apple will change this, you’re wrong. This was already the same behavior in previous versions.
As an Aperture user, I just don’t want to hear about LR (nor jpeg). So I never use HTP, just trying to expose correctly and recover what needs to be recovered with Aperture tools !

How it is it that Lightroom has no problem with highlight tone priority? What are they doing differently than Aperture?

LR is not AP ! I presume AP uses the OS X based RAW engine while LR uses its own one (should be interesting to check with C1)
A long time ago, a well known french astrophotographer made an in depth analysis of HTP : a HTP RAW file is exactly the same as a non HTP one (for a strictly same image of course) minus one stop.

I think this is common to all non-proprietary raw converters - with one exception: Apple give you ONE profile for the cameras they support, which takes no account of Picture Controls, D-Lighting (I use Nikon, but the same applies to Canon etc equivs.). Adobe have chosen, in Camera Raw, to provide different profiles to “Adobe Standard” which seek to replicate the Standard, Vivid, Neutral and other Picture Controls. I can only assume that the Canon HTP may be read as “active” from the exif data, which allows Camera Raw to apply its interpretation of the raw decode needed to render this. Of course, the proprietary converters, NX2, DPP etc, can fully read the settings chosen to render an appropriate version of a raw image.

I also find that Aperture renders my D3S (and prior D3) raws as somewhat darker than NX2 will show them - these are just straight “Standard” Picture Control-shot images, no modification to the in-camera processing. I haven’t been able to really get a handle on just what I need to do to get the A3 raw image to look like an NX2 from a brightness point. It would seem to be more than just +0.3/0.5EV for example. I have found that adding 0.1 Brightness and then +0.15EV does help, but there’s more going on to the Nikon version of shadows and midtones that needs a better curve than I can create…

The reason, despite this, I persist with A3 is that it is far less clunky than NX2, and I find the way it renders colour to be more to my taste in any event. I recently downloaded the trial version of LR4 to explore this further and whilst the extra Adobe profiles do give you choice (including brighter rendition of straight - non D-Lighting- images, I just cannot get my head around the interface and controls any more. Considering I started shooting raw on LR2 this, to me, demonstrates that the A3 interface and way of working is better.

same annoying issue here with Nikon D700RAW files. While importing, In-camera previews look fine then these are replaced by Aperture’s ones, which are a lot darker. D-Lighting settings don’t seem to make any difference. I think this behaviour must be fixed asap!

All this would be improved no end if camera makers stopped dabbling in software and just made all the RAW information available to the software companies.

I shoot Nikon and the RAW files are unaffected by the settings for anything like Picture Control, D Lighting etc. However the expensive Nikon Capture NX software (not provided free even with D3 or D4!) does read the settings that were in force when the shot was taken and use them in rendering the RAW if you want it to.

Aperture does not do that. The reason the thumbnails in camera look different is because the camera DOES do that.

Unfortunately, Nikon have chosen only to make the relevant keys to those parts of the file available with Capure NX (which costs over $300 here!).

I’m now importing the 3 8GB flashcards (1000 images or so) just shot in Iceland with my Nikon D700 into Aperture via Nikon CaptureNX2 in order to avoid the darken issue and it’s working.
But the extra time this involves is enormous, and the space now taken up compared to NEFs is HUGE and my library is bloating!
I chose Aperture as my sole solution for importing, editing and managing my photos, but this disappointing issue is really compromising my choice. I hope someone wises up (whoever is responsible for it) and fix this problem asap, before they start loosing on their sales.

NIKON shooters — please read and reply.

For those of you here commenting on seeing the “same problem” with Nikon cameras, I want to be sure that you’re actually seeing the same thing, as I suspect this is not the same issue at all.

The Canon issue is very specific to enabling the “Highlight Tone Priority” mode in the advanced settings of the Canon dSLRs. When this is enabled (and the problem now appears to be far more widespread than just the new Canon cameras), images imported into Aperture are far darker and grainier than they should be.

Nikon users reporting a darkening of images with or without various modes enabled may simply be seeing the difference between the camera-rendered JPEG and the RAW decode. It’s very important to understand that any image settings set in the camera — contrast, saturation, etc. — are not going to be carried through to the RAW file. When shooting RAW, it’s usually best to set your camera to fully neutral color settings so that you’re not misled by the in-camera JPEG, which is what you see when you view the image on the back of the dSLR, as well as is what you see when the image first loads into Aperture, before it is decoded by Aperture and the camera JPEG is replaced.

If you really like the settings your camera produces, you can always shoot RAW+JPEG so that you have both in Aperture — the JPEG that the camera created, as well as the RAW decode that Aperture creates.

The most extreme example of this is if you shot in a B&W mode in camera. You would see B&W images on the back of the camera, in the import window, and even initially once imported into Aperture. Of course as soon as you clicked on one of those RAW files, you would see the B&W JPEG preview replaced by a RAW render.

So again, Nikon users, please respond to this to confirm what you’re seeing. Set your Nikon to have no color adjustments applied in-camera, shoot a few pictures, and import. The result should be very similar (it will never be identical) to what you saw in camera, and in the import window, and before you clicked on a RAW file and saw it rendered by Aperture.

If on the other hand you can confirm that there is a mode like Canon’s “Highlight Tone Priority” that’s resulting in dramatically different photos in Aperture, this we want to know as well.


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Hi Joseph,
I just tried shooting two photos with Nikon D700. The no.1 with Active D-Ligting OFF, the no. 2 with Active D-Lighting HIGH (all the other settings are set to off , or neutral apart from long exposure NR filters)
I do notice the darkening while importing in Aperture, and none when imported in Nikon NX2 (trial mode).
To my account this is the same kind of behaviour observed with the Canon “Highlight Tone Priority”.
Here below the links to the images, so you all can be the judge (filenames should be self -explanatory):

Hope this helps


Thanks for doing that. To my eye, both images run through Aperture (DLightHIGH and DLightOFF) look far better than the two run through NX2. I can see marginal difference between the OFF and HIGH images (from either software), but to be fair the feature shows itself best in extreme highlight situations, like direct sun on a shiny textured surface or something like a wedding dress.

Since both HIGH and OFF images are virtually the same in both software, I would say that this is proper/correct/intended behavior. The images should look essentially the same, and they do. The HIGH image isn’t a stop darker than the OFF image, from either application.

The fact that the Aperture one has stronger shadows and is more saturated is more a “look” than anything else, and frankly I think it looks great. The NX2 image looks very flat, and in need of processing.

Do you not agree?

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Hi Joseph,

I stand by my original comments.

On a D3/3S raw image, shot at neutral “hands-off” settings (no D-Lighting, only unaltered standard or neutral picture controls, no colour adjustments), when imported into Aperture, the raw rendered is noticeably darker than the Jpeg preview, or the raw rendered by Nikon NX2 using the same “hands-off” settings.

I feel Apple’s raw fine-tuning needs to allow some increased brightness, at the very least, to better match the raw to Nikon’s intended output. As it is, when you look into the brick, the settings for such are at their maximum.

This is somewhat frustrating as it means you are committed to doing some work immediately, just to replicate in Aperture what might be a quite acceptable Jpeg.
There also seems to be some difference in rendering the lower mid-tones and upper shadows between Aperture and NX2, with, again, NX2 being the brighter - possibly more realistic but anyway more to my taste as a newspaper shooter. Beyond my meagre skills to explain properly, sadly… :)

But as I said, I will persist.


Thanks Andy. All good information.


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Hi Joseph,
I see your point, but I have to disagree. I too initially thought that the Aperture images were more attractive, because more saturated and darker (in some cases, the skies seem shot through a polarizer filter, compared to the NX2 or in-camera preview, which is definitely more pleasing to the eye than a washed-out one).
But these are few instances (and yes, the ones I shot and posted earlier aren’t good examples).
Overall, looking at hundreds of images while being imported, I see the way Aperture develops files is not correct: too many are way too dark and details in the shadows just disappear when the preview changes from in-camera to Aperture’s (then the reds are way too saturated and other minor differences, like loss of details in highlights).
And I’m positive, this behaviour started some time ago (can’t say when and on what version, though). Before it never happened.
In short, I prefer doing the processing in those images that need some, choosing them from the whole run of neutral looking, rather doing the opposite to the vast majority of photos in order to bring out the details and tone down the colors.
Not to mention that, while shooting, it makes very difficult to predict what the photo will look like once processed!
Having said that I hope to be wrong and that the solution is ‘round the corner and someone would point that out to me!


Thanks again. And hey, “the customer is always right”… if these images are too dark/saturated, and the RAW decode is at max brightness as Andy said, and you’re sure this is a recent development, then I’d say there are issues afoot.


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Here’s the situation. Aperture in its latest version is improperly processing raw images. Period.

I am sure that there are different nuances with different camera manufacturers and file structures, but the fact of the matter is this recent version is processing my raw images that look fine for raw images in camera and initially when they are imported by aperture. However generating the previews darkens them significantly, shifts the color, and adds grain as though it was taken in low light with a low ISO. They look awful. THIS DIDN’ T HAPPEN BEFORE.

Additionally, I am pulling up older libraries that were processed long ago by previous versions of aperture and this one is reprocessing them with pictures that I had perfectly tuned and it is now reprocessing the master images (yes, they are master images– what Apple now calls originals) and also reprocessing the versions which are now much darker and the color has shifted. This is completely unacceptable. I am not interested in going back and re-editing tens of thousands of pictures because the latest version of Aperture’s RAW processing was broken from a working, stable form. I don’t even want to open older libraries in fear that it’s going to redo my previous assets and screw up everything I’ve been working for over the past 5 years.

The fact is also that this problem did not happen before this previous version of Aperture. There is no such camera setting in the Pentax domain for setting a dynamic range for the highlights that I can find. Anything that remotely looked similar is having no significant observable affect with new pictures.

Plain and simple, Apple has screwed up the raw processing and change something they shouldn’t have any need to. Change it back or fix it immediately. There is no excuse for this. Fix it. Now.

If Apple doesn’t get their stuff together regarding their professional software, I’m moving to Premier and LR. I’m getting tired of Apple turning their professional products more more into glorified versions of their toy software apps.

Tried turning off “Highlight Tone Priority” after Joseph linked me to this article.

Sadly on my T4i it does not solve the issue.

I sent another bug report to Apple but those wheels turn slowly.

Am I going to have to switch to LR4?

I don’t know if this is relevant, but it may be a significant clue.

Towards reducing the bloat in my lib, I deleted all of the previews for most of the older parts of my library (all still on backup), and re-generated previews only for the ‘keepers’ (I could’ve selected only the non-keepers, but …).

Anyway, in glancing thru the new previews, one type was garishly off: all keeper photos that started in color that resulted in some of my best b&w’s were now nearly blown-out in the highlights (I won’t detail the preview restoration process).

Given that this seems to be manifesting in the realms of exposure and highlights/shadows, and given the noticeable differences between in-camera jpegs and Aperture’s previews, I thought about recent changes to the Aperture market, and it got me wondering:

…with the ever increasing ease by which iPhoto users can migrate into Aperture, and given (educated guess) that most of the photos migrated from iPhoto are not RAW (i.e., jpegs), might Apple have made adjustments to the preview renderer to improve the rendering of ‘simpler’ jpegs so that iPhoto migraters would be more pleased (or at least not turned-off by) how the same photos now look in Aperture?

Unless the preview rendering engine differentiates among simpler jpegs (from p&s’s, etc.), more accurate jpegs (from higher-end cameras), and RAW, changes to the preview rendering engine may be having adverse effects.

Shots-in-the-dark perhaps, but it may awaken uncovering more accurate causes.


Has anyone with Photo Mechanic tried toggling the RAW decode on and off, ( Q button I think), to see if the same problem is exhibited ?

Andrew Mumford

In my quest for a solution, I came across Nikon Picture Control presets for Aperture, by MacCreate. Is that the solution ? Their website bounces back to ApertureExpert, as announced on AE sometime ago, still I find strange they weren’t mentioned

PS: Aperture shows the same behaviour with my Fuji FinePixX100 RAF files…
do you notice the same, Joseph? (i think you have the same camera, right?:)


The Nikon Picture Control presets are no longer available. That was a MacCreate product that is not available here.

I think everyone is getting a little over-analytical of the photos and seeing problems where there aren’t any. I’ll say it again — It’s important to remember that the RAW file will not look the same as your JPEG. You’re talking about two different computer systems analyzing the same file and producing a JPEG out of it — the camera and it’s internal software vs. the Mac and Aperture.

I rarely shoot RAW on the X100 and if I do the images don’t look anything like the JPEGs, but that’s also because I have my JPEGs tweaked dramatically.

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Hello guys.

Checking off “Highlight Tone Priority” (or some equivalent setting) cleared the issue for pictures taken with my Pentax K5. Thanks for pointing me in the right direction.

I have found my way to this post as I am having the same issues with a D600 where images that look fine in camera and on upload ‘darken’ automatically when I click on the preview thumbnail to load.
If left alone on the thumbnails they appear fine.
Its when I highlight they auto adjust to ‘too’ dark and I have to then re edit to recover the image to normal…that is, what I shot it at in my camera and in my minds eye etc.
None of this used to happen…its a new development that is driving me crazy


What you’re experiencing can be explained in this FAQ post (which actually just links to this article).

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