straight

Very odd…

My laptop is also a MacBook Pro 17" (Mid 2010) on OS 10.11.4 and my desktop is a Mac Pro (Early 2009) on OS 10.10.5. You also indicated that the bug occurred on Aperture 3.4.5 (with an older OS).

So far, you’re the third person that has documented this bug and I’m the only person (so far) that can’t reproduce it. Many “straightening” adjustments are small and may not be noticed when exported. However, if the bug started with Aperture 3.4.5 and is now just being reported, I would guess that it impacts a minority of users.

There must be some other factor that triggers the bug besides just using straighten and levels adjustments (possibly file type?). I have tried it using scanned TIF files, JPG, plus Nikon D800 and Lumix G3 raw formats.

I am very interested in this issue, plus any other issues that may occur using OS 10.11.x. I have avoided upgrading my main Aperture computer (Mac Pro) to El Capitan until I’m certain it won’t cause problems. I use straighten and levels on most of my scanned images and it would be a major problem if this impacted my workflow. I still have many thousands of old family photos to scan and edit. I don’t want to move away from Aperture until this project is complete. However, from your comment regarding Aperture 3.4.5, this doesn’t appear to be specifically an El Capitan issue.

Perhaps the White Balance makes the difference.

I have just tested in the split view browser, where I can see the enlarged image and thumbnails as well. As soon as I enable the "Levels" adjustment, then horizon as seen in the thumbnail will tilt back to the original angle, and any other adjustment I add, will just make the horizon tilt up and down, but the image will export without the straightening.

Still can’t reproduce the issue. I tried with white balance on and off. I also tried adding exposure and enhancement adjustments (all cases with levels and straighten “on”). The main viewer, thumbnail and export version maintained the adjusted “straighten” in all cases.

Grasping at straws here, but could the issue somehow be related to the iCloud photo stream? I’ve had such bad luck with Apple’s “Cloud” and sync services that I’m getting paranoid about using them (I don’t use photo stream with Aperture).

The bug only happens with some of my projects,

Does it happen in a new Aperture Library for you as well?

I tested with a brand-new Aperture 3.6 library, created for testing. I imported three JPEGs.

I edited them with the Straighten Tool, then added an "Auto" Curves adjustment.

When straightening them I tilted the horizon to the left. As soon as I added the Curves adjustment, the horizon in the thumbnail tilted to the right.

So the bug is probably not, that the Curves disable the straightening, the Curves modify the straightening angle. I suspect a programming error with uninitialized values or array indices out of bounds, as the results are so random.

And the effect changes over time.

After adjusting more photos in the same way, the results changed.

Now the tilt is still slightly off, but at least in the same directions for all photos - it is random and not easy to reproducible.

If the bug is caused by a program error that is dependent own uninitialized variables or code accessing data out of bounds, the amount of the error may vary. So you will see it or large values of straightening and for smaller angles not at all.And it may change over time, as shown in my last screenshot above.

Sometimes adding the Curves will even corrupt the thumbnails and the exported image:

Same issue here. Activating the levels adjustment undoes the straightening in all thumbnails and exports.

Entering an angle opposite to the correct one is the only workaround that worked to export the photos as intended... Actually sometimes (randomly) it even fixes that particular photo, so that the main view and the thumbnails are in sync again.

I'm so glad I found this thread! I've been suffering from precisely the same problem/bug for about two months now.

I had already figured out through trial and error, as I see the rest of you have, that the bug only occurs when both Straighten and Levels are active simultaneously. Unclick one or the other, and everything is fine.

And, as some of you have reported, it is also not universal for me. Some of you have said that the glitch does not affect all projects.... My experience is a bit different: it varies within a given project, only affecting some photos but not others. That said, it does affect the majority (but not all) of the photos within every project.

My workaround: use the Straighten tool alone to straighten the image. Then export it. Then import the exported straightened image. Then apply levels to it. This is a big pain in the butt, but it does work.

Very grateful for this thread: I too am having this problem.

I discovered that the addition of any one of a number of other adjustments causes the Straighten to start working again. For instance, adding the *slightest* Shadows adjustment (0.25) results in the Straighten adjustment working for me again. Others which also fix the problem: Highlights; Mid Contrast; Contrast; Definition; Vibrancy (but not Saturation); Recovery; Black Point; White Balance; Noise Reduction; and possibly others.

Good to know, Andrew. Any of these is better than "Auto Enhance".

@Andrew, THANK YOU for the patient research/testing, and the detailed list of which adjustments solve the problem. I'm hugely indebted; I'm sure many others are as well.

I don't seem to be able to click on "This helped me" so I'm saying it here: This helped me Andrew.