p.1 #1 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
First of all, thanks to DPreview which pointed us in the right direction on their review!. But it is not mandatory to use an HLG gamma: the camera zebras are very similar in all gamma curves.
And fortunately they can be setup to faithfully represent the RAW image clipping. Only in the extreme borders and corners they tend to not show the full extent of the clipping (why?) but the rest of the frame is 99% accurate, both in size and shape. And no tricks are required! (like further exposure compensation). This gives the users of Sony cameras an edge in exposure control compared to Canon/Nikon (well, some Canon models support Magic Lantern, which at least shows the clipping... after shooting).
The key is that in order to show the clipping when the RAW data actually clips, a custom zebra level needs to be configured (and none of the built-in default presets is valid). If no picture profile is enabled, the proper setting is 107+ or 108+. For picture profiles using HLG/HLG3 gamma it is 100+ (not the camera default 100+ but a custom 100+, which curiously is not exactly the same). However that mode has the minor downside of skewing the reported ISO levels by 1/3 EV (ISO 100 becomes 125, ISO 640 becomes 800, and so on). Alternatively HLG2 doesn't changes the ISO levels and requires 95+. A mode you must avoid like the plague however is HLG1, because doesn't uses the sensor full well at any ISO setting.
To prove that this is accurate I'll post soon some examples, comparing shots of the back of the camera in Live View with the actual RAW zebras after shooting.
It is important to be aware that camera zebras are based only on the green channel, which still is useful enough in most cases.
This is currently my setup:
Enable the picture profile PP10 (which is already configured with HLG2 gamma by default and other proper settings). Of course, this doesn't affects at all the captured RAW image. ISO continues starting at the normal value of 100.
Set the zebras level to Custom1 or Custom2 configuring it for "lower limit 95+" (experimentally discovered, but not an arbitrary value: it is just the video output documented by Sony when the gamma input maxes out in that mode).
Setup the Gamma Disp. Assist to Auto (I think it is Off by default). Otherwise the viewfinder is awful in many gamma modes, including those based on HLG. This has absolutely no impact on the zebras.
By the moment I HAVE NOT changed the black level on the picture profile (lowering it enhances the contrast, but does affects the zebras threshold). The saturation however has no impact on the zebras (rising it a notch could be useful).
If you are in Av mode and have enabled the Highlight metering, you should select the Entire screen Avg instead. I assume the same is recommended for M mode with auto ISO. This is to make it more unlikely the exposure compensation to go beyond +3EV (too easy on overcast days while using the zebras for ETTR in Highlight metering).
Do not setup a freaky WB like UniWB (the camera presets seem fine, including AutoWB, as well as a real life custom WB).
Another advantage is that the histogram in the picture review is nearly RAW in the green channel (the blinkies don't work, though).
VERY IMPORTANT:
In Av mode, just at +3EV of exposure compensation, the zebras ALWAYS stop updating! (they don't grow more, or may not appear at all, even if you continue pushing up to +5EV). That is a compeling reason to not to use Highlight metering.
In manual exposure mode (M) the zebras also stop updating under 0EV (e.g. for exposures longer than 8sec at F2.8 and ISO 100) but likely you'll not be looking at them by then.
p.1 #2 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
This all sounds very complicated for something that ends up determining a simple combination of aperture, shutter speed and ISO.
What does this do for a photographer compared to the more straightforward ETTR approach, or the newer ones that have been established as working quite well?
p.1 #4 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Thanks for sharing. I've been using zebra for showing potentially blown highlights as well and it is indeed very handy.
Zebras not only could show when a highlight is blown out but more importantly, where it is which is useful to ignore specular highlights vs. some details you care about.
I appreciate the details but feel that the real message gets lost for those who are not familiar. This is what I use:
- In stills mode, choose Zebra Level Custom2 Lower Limit 107+
- In video mode, choose HLG2, Zebra Level Custom2 Lower Limit 95+
I use Zebra in conjunction with ETTR as implied above: the histogram doesn't tell you where the blown highlights are.
p.1 #6 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Zebras are very common in video shooting, especially in the days of limited DR in the highlights. I've tried using it a few times on the Sony but find it very distracting and misleading in stills. Since video is not being saved in raw yet on this camera, it's more important to use it. Maybe this new info will help me set it up to be useful. Thanks for the research and advice!
p.1 #7 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
mjm6 wrote:
This all sounds very complicated for something that ends up determining a simple combination of aperture, shutter speed and ISO.
What does this do for a photographer compared to the more straightforward ETTR approach, or the newer ones that have been established as working quite well?
The camera has no ETTR metering, and the zebras are just another way to get there. Most of my post is research about their limitations, but normal users will benefit just by a single setting: a custom level "lower limit +107". Otherwise, they are totally unuseful and intrusive.
p.1 #8 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
I’m really liking the highlight metering as it’s been working quite well without any fuss or even thinking about it. To me this just sounds like to much fussing around and not getting images. It was my biggest pet peeve when teaching workshops was people would be screwing around with settings and not concentrating on taking images. Not saying this is bad but photography should be or I believe it should be the shortest tech path to great images and ART. Today we have so much latitude with DR and great raw software that I believe this is a little overkill. That’s my opinion and I’m sure someone will say something different. To be honest if it takes 4 paragraphs to explain it than you lose me. I’m about simple paths to great images. I do not want to play engineer in the field. That’s me though
p.1 #9 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
photomadnz wrote:
Agreed! Great work but surely way overly complicated? Ill stick to using the highlight with exp comp I think :-)
I have found that highlights metering +2EV usually gets short in overcast days (or uniformly illuminated subjects) by about 1.5EV or more compared to the maximum possible exposure. That is a lot of "ETTR room" lost. While in sunny days or high contrast scenes it usually overexposes by about 2/3EV, leaving you in the hands of the channels recovery ability of the RAW converters (and they don't necessarily tell you that the picture is actually overexposed).
The sample photo I posted yesterday in this thread was shoot using Highlights metering +2EV, and has lots of burned areas in the actual RAW data. The processed jpeg doesn't looks that bad, but indeed a lower exposure gests a better picture, specially with these great Sony sensors.
p.1 #10 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
fnf_ wrote:
Thanks for sharing. I've been using zebra for showing potentially blown highlights as well and it is indeed very handy.
Zebras not only could show when a highlight is blown out but more importantly, where it is which is useful to ignore specular highlights vs. some details you care about.
I appreciate the details but feel that the real message gets lost for those who are not familiar. This is what I use:
- In stills mode, choose Zebra Level Custom2 Lower Limit 107+
- In video mode, choose HLG2, Zebra Level Custom2 Lower Limit 95+
I use Zebra in conjunction with ETTR as implied above: the histogram doesn't tell you where the blown highlights are....Show more →
I find the 107+ for the stills mode with no Picture Profile (or with Picture Profile 2, which is the same) not so comfortable. To the point that I also use HLG2 for stills, but enabling the Gamma Assist to get a "beautiful" rendering in the viewfinder.
The reason is that sometimes, the camera shows "traces" of zebras in the full image. Using HLG2 they may dissapear or be definitely confirmed if you zoom in in that area. Using the Stills gamma, however, the zoomed image may still have traces of zebras, leaving you in doubt. That has nothing to do with the zebras level (even set to 109+ the traces are still there, while in HLG2 setting 94+ or 96+ would have a clear and noticeable impact). Perhaps in levels beyond 100% we depend on maths rounding or projections not so accurate, who knows.
p.1 #11 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Now the promised photos, comparing in-camera zebras with actual RAW data clipping (using the tool introduced in this post). What I'll demonstrate is that in-camera zebras are valid as a DIRECT and accurate exposure guide. That is, no need for tricks like dialing additional exposure compensation. And you MUST NOT see the zebras to be sure that the image is properly exposed (except for a few specular highlights or image areas not of interest). The fact that DPreview recommended just seeing them was likely related to the zebra level selected.
For this test I used the proposed setup (HLG2 and custom zebra lower limit 95+), but the results will be the same to those obtained by HLG and custom 100+ level (the in-camera 100+ default setting is actually more close to 99+) and also very similar to the standard Stills gamma with a 107+ or 108+ zebra level (for those who don't want to set a Picture Profile, or use the PP2).
In all the images: at the left the photo of the back of the camera near the moment I shot. At the right, the shot actual RAW data to compare (anything in color or bright white represents true clipping). I started from 1/80 sec. By then it there was mostly one clipped area in the whole image. The camera zebras show it well, despite this area is very close to the image borders and corners:
In the next crop, the "KPMG" characters are not totally clipped, despite the zebras suggest that. I assume that zebras are a "projection" of the actual exposure selected, which will be actually performed when shooting (so maybe there is certain margin of error):
Now zooming even more. We have less resolution here in the RAW crop due to the binning applied during demosaicing (the camera LCD at full size and 200% is much better!):
Another +1/3EV and the sky continues clipping. The camera zebras struggle in the left and right sides, but in "center weighted" terms are very good (one could always recompose for metering ;-D). At least at this hour, the sky clips first in the green channel, which is good, because otherwise the zebras wouldn't have reported it:
Nevertheless, if we zoom at 1/5 the height of the frame in this photo, the zebras are accurate. Note that the blown red area has no zebra, as we expected (remember that zebras follow only the green). The yellow (which is the addition of green and red) does has zebra thanks to the burned green:
The previous example is truly amazing. We are much under 1/3 EV of accuracy. I'd give it without hesitation (what I don't want to give is a stop and a half!). Note that the zebras are in motion, and shooting the back of my camera freezes them reducing their full "meaning". They move:
I'm really happy knowing that I have in the field a tool capable of setting the best exposure. And zebras are much more useful than a histogram, because many times a photo requires some clipping. Of course when they work as expected (e.g. do not appear when they must not).
If you decide to use this method in Aperture Priority, please do not forget to ensure that the exposure compensation NEVER GOES beyond +3EV (+3.0EV is safe); otherwise the zebras become totally fake.
p.1 #12 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
cgarcia wrote:
First of all, thanks to DPreview which pointed us in the right direction on their review!. But it is not mandatory to use an HLG gamma: the camera zebras are very similar in all gamma curves.
And fortunately they can be setup to faithfully represent the RAW image clipping. Only in the extreme borders and corners they tend to not show the full extent of the clipping (why?) but the rest of the frame is 99% accurate, both in size and shape. And no tricks are required! (like further exposure compensation). This gives the users of Sony cameras an edge in exposure control compared to Canon/Nikon (well, some Canon models support Magic Lantern, which at least shows the clipping... after shooting).
The key is that in order to show the clipping when the RAW data actually clips, a custom zebra level needs to be configured
It is important to be aware that camera zebras are based only on the green channel, which still is useful enough in most cases. ...Show more →
Thanks for sussing this out and posting. I haven't used Magic Lantern in some time but it will
enable RAW based Zebras in all channels if desired pre-shot, assuming using Live View of course. https://www.magiclantern.fm/forum/index.php?topic=12096.0
I would rather have a mirrorless FF cam with a wide DR sensor than a new Canon right now though.
That be said, I had a rented an A7RII pre A7RIII being released for a trip to Bhutan with MF lenses with Zebras and focus peaking enabled and sometimes mis-focused shots as became confused as to what was what. Too fancy for my own good on a camera that was new to me. I had fun configuring the cam, but would rather have the shots. I don't see why the OEM's just don't enable RAW zebras in the menu as it is clearly able to be done.
p.1 #13 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
'Today we have so much latitude with DR and great raw software that I believe this is a little overkill.'
It appears to be a 2018 solution in search of a 2005 problem - Canon's 2005 5D was three stops of DR below modern Sony sensors, and had seriously ugly noise. Also exposure is always a choice, there is no 'best exposure' (added for newcomers).
p.1 #14 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
I am back to good old matrix metering and also fast continuous bracketing if the scene asks for it. Like strong backlight.
I tried H+2 as well as Zebras.
Thing is none of this works in all conditions. You still need to figure out EC you have to dial in depending on the light. It can be +1 or +2 or whatever.
This may work in tripod locked in situation but fir a fast developing scenario, no.
Of course in a slow scenario above works but trial and error is still there and then if i have time i can just repeat the shots with EC or bracket.
But my gripe is that i have difficulty later on when everything is ETTR. I need to judge the vibe of the scene and how it looked when i shot it, and Matrix does that.
p.1 #15 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
this is overkill. i don't wanna be so technical during the shoot and forget the most important part - taking photos.
I'm more of a portrait guy so i wanna control the DOF so i will just go using AV Mode AUTO ISO -2/3EC and pop some strobe light.
Highlight priority is an excellent guarantee your sky isn't blown out but your foreground will be too dark. You can do +2EC but it beats the purpose as the bright areas will be affected by the EC as well so might as well just use the good old matrix metering and just do -2/3EC.
p.1 #17 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
mjm6 wrote:
This all sounds very complicated for something that ends up determining a simple combination of aperture, shutter speed and ISO.
What does this do for a photographer compared to the more straightforward ETTR approach, or the newer ones that have been established as working quite well?
What never ones?
p.1 #18 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Anyone have success replicating this on the A7R IV? I've tried no PP 107+, 108+, and 109+, the last one being 1.5 stops too early. I also tried Neutral Creative Style with Natural Image Style, 109+ and it was stll too early. I am using Lightroom but can definitely still see detail in the areas with zebras when reducing the exposure.
I also tried PP 10 and 95+ and it is around the same amount off.
cgarcia wrote:
In Av mode, just at +3EV of exposure compensation, the zebras ALWAYS stop updating! (they don't grow more, or may not appear at all, even if you continue pushing up to +5EV). That is a compeling reason to not to use Highlight metering.
Sad to report that this is still the case on the A7R IV. In fact, the viewfinder itself does not update after +3.0 EV.
Would love to know of a solution. It seems like it might be possible with HLG, but I'd rather have a solution using no PP, as I don't want to do any grading on my videos.
p.1 #19 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Eruditass wrote:
Anyone have success replicating this on the A7R IV? I've tried no PP 107+, 108+, and 109+, the last one being 1.5 stops too early. I also tried Neutral Creative Style with Natural Image Style, 109+ and it was stll too early. I am using Lightroom but can definitely still see detail in the areas with zebras when reducing the exposure.
I also tried PP 10 and 95+ and it is around the same amount off.
I am curious about this on the IV and V as well.
How did you determine 109+ is 1.5 stops too early? Especially since you can only adjust in 1/3 stops
p.1 #20 · Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)
Easy way to use Zebras
Begin watching from the 18.53 mark, you will see how to set up your Zebras.
To control your zebras you use your control wheel to adjust your ISO. You need to go into the setup section and assign control wheel for ISO Watch from the 39.1 mark. He will demonstrate using the control wheel to control ISO for the Zebras..... Essay Peasy to control your Zebras, if you wish to use Zebras
