olegkin wrote:
I have noticed that the blue channel clips easily on both the q3 and the a7r6, even when the histogram looks fine during live view. It is recoverable most of the time, but it is annoying to adjust it in post. If the sky is in the frame, I have to "underexpose" by a stop or more relative to the histogram. I mention the q3 because it uses a Sony sensor, and that is where I first saw this behavior.
With the a7r6, I went outside, aimed the camera at the sky, and adjusted the zebra settings so that the zebras disappear right at a correct exposure. I landed on a setting of 85. Zebras are new to me; I had not used them before. YouTube suggested something around 107 to 109 (on the older a7R models).
I arrived at roughly -0.5 stops of exposure compensation, which keeps the blue channel easily recoverable, or prevents it from clipping altogether. This also depends to some degree on color temperature.
Is there a different way to handle this? Am I missing something?
Using the A7r-V to shoot lossless compressed RAW files only, with the zebra threshold set to 107+, I very infrequently noticed a couple of the brightest areas in waterfall photos had an odd cyan color cast. These are always long exposures (in the 0.5 second range) captured on cloudy days. The areas are small, but larger than tiny specular highlights, which really don't exist in these conditions. The very light cyan patch in the middle of a neutral highlight is very noticeable, and I found it to be unrecoverable except by using a brush in Photoshop to desaturate the spot, making it the equivalent shade of grey. If this was not a true overexposure, it would be recoverable in the RAW file, and it definitely is not.
I am certain there were no zebras on any of the offending highlights. I also know that setting the exposure 1/3 stop higher did create zebras on the same highlights.
I haven't changed any of the JPEG settings and all are still at their (auto) default. I have noticed that the AWB (based on the "as shot" white point in ACR) is always on the cool (blue) side of the ACR default for the conditions, and the ACR "auto" setting for the image, and what ACR measures based on me selecting a bright neutral area in the photo. Perhaps adjusting the JPEG white balance for the prevailing conditions in each photo would fix this, but fussing with that is a hassle considering that I don't even have the camera record a JPEG file, except the one it embeds in the RAW file.
Because this has happened only two times in 1.5 years and around more than 50 different waterfalls, I'm not very excited about it. In fact I'd forgotten about the issue until your post reminded me. My "plan" for now is to set the zebra threshold set to 106+, be more aware of the issue, and see what happens.
Thanks reminding me about this issue. Since our shooting situations are very different my "solution" probably won't help you, but I do think adjusting the WB setting may be on the right track, and a more proper way to go about solving the issue.
Jun 11, 2026 at 06:53 PM
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