Sony Sony Underates their Sensors?

[Brownie]

I was watching a video comparing the A1 to a Z9 and the narrator made a comment that Sony underrates their sensors by 1/2 - 2/3 of a stop. They do this so you have less chance of blowing out the top end while still allowing enough latitude in the shadows. I've noticed that when processing I sometimes need to add a little to exposure. In talking to other Sony users, many overexpose. I've not, but it clicked when I heard him say it.

Do any of you notice this? Do you overexpose?

I've searched the internet using every term I can think of but cannot find another reference to this anywhere. Does anyone have something that could substantiate this? Not that it matters much in the long run, mostly just curiosity.

 

[Brian]

Nikon did this with the Nikon FE back in the 1970s, to prevent slide film from blowing highlights.

 

[RichardC]

Nikon did this with the Nikon FE back in the 1970s, to prevent slide film from blowing highlights.

You have a very good memory.

 

[WhidbeyLVR]

Wasn't this essentially what Olympus did at ISO 200 with their 16-20 Mpixel sensors, with "low ISO" (100) being shooting with the guard rails removed?

 

[Brownie]

Wasn't this essentially what Olympus did at ISO 200 with their 16-20 Mpixel sensors, with "low ISO" (100) being shooting with the guard rails removed?

Panny did the same, I just assumed that was a product of the smaller sensor?

 

[Brownie]

Nikon did this with the Nikon FE back in the 1970s, to prevent slide film from blowing highlights.

The Nikon FE had a sensor?

 

[bdbits]

I've not heard that before, but do find I often want to push exposure up a bit in post when I was relying on metering. I often rely on the viewfinder even for my usually fully manual exposure, unless I am in really bright light or other conditions that I know might throw me off. Then I pay more attention to the meter. But my subject(s) are not usually moving much or at all, so this works for me.

I could understand the thinking but would be surprised if Sony does this. I think they would get a lot of pushback from professionals in particular if they were consistently underexposing.

 

[Brownie]

I've asked this on another forum and almost without fail, people do in fact push exposure. In the same video, the narrator stated that in cases where the sensor struggles with noise in shadows, some manufacturers over rate ISO settings to give more detail in the low end at the risk of blowing out the high end.

I have yet to find anything to confirm any of this. But practically speaking if so many are overexposing or pushing in post, it sure seems credible.

 

[William Lewis]

The Nikon FE had a sensor?

Yep. And it was annoying that you had to replace it every 24 or 36 exposures...

 

[will focus]

I was watching a video comparing the A1 to a Z9 and the narrator made a comment that Sony underrates their sensors by 1/2 - 2/3 of a stop. They do this so you have less chance of blowing out the top end while still allowing enough latitude in the shadows. I've noticed that when processing I sometimes need to add a little to exposure. In talking to other Sony users, many overexpose. I've not, but it clicked when I heard him say it.

Do any of you notice this? Do you overexpose?

I've searched the internet using every term I can think of but cannot find another reference to this anywhere. Does anyone have something that could substantiate this? Not that it matters much in the long run, mostly just curiosity.

I find myself shooting at + 1/3 often.

 

[Brownie]

I could understand the thinking but would be surprised if Sony does this. I think they would get a lot of pushback from professionals in particular if they were consistently underexposing.

I don't think it would affect a pro, or anyone with common sense. I'm so effing anal about this stuff I've tried to stick to the meter, contrary to my better judgement. A pro is just going to use whatever setting is necessary without giving it a second thought. Don't be like me.

 

[Darmok N Jalad]

If you can set your highlight zebras to 100%, (if that is a thing on Sony), you could find out. I set mine that way, and expose until the zebras are gone. That often leaves the final result underexposed.

 

[Brownie]

If you can set your highlight zebras to 100%, (if that is a thing on Sony), you could find out. I set mine that way, and expose until the zebras are gone. That often leaves the final result underexposed.

Sony has Zebras, never use them on these or any other cameras. Might give it a try. Darktable has auto exposure in the exposure module. I was thinking I'd take the same shot using the meter for under exposed, properly exposed, and over exposed by 1/3 and 2/3 stops, and see how Darktable treats them.

 

[bdbits]

The usual recommendation for Sony zebras is to use a custom setting of 107+. I do not recall precisely why 107+ but it made sense when I looked into it. If you want to know more a search should turn up lots of info, but I am feeling too lazy to find a link at the moment. Lunch was pretty filling, lol.

 

[bdbits]

So I found a discussion from 2018 about it on FM. Configuring the Sony A7R3 for RAW zebras (yes, WE CAN!)

Basically, like histograms the zebras are actually based off JPEG data. But RAWs have more recoverability on the highlights than JPEGs, and it turns out that 107 is the magic number that matches up to where the RAWs would actually start to blow out the highlights. Now if you happen to be using JPEGs, I think that means you would want to leave zebras at 100. Also, this discussion was on the A7R3 (the 4 was new at the time) so with later bodies, I suppose it could be different. There may discussion about other bodies elsewhere in the thread; I linked straight to a post where it was tested in depth for the A7R3. Since I have an A7R3 I did not look further.

 

[UnderOpenWater]

Per Mark Galer (Sony guru extraordinaire), the zebras on my A7III are set to 109+. I don't know if they are the best, but they seem to work well for me. Here is the link: Zebra 109+ for Sony Raw Photographers

 

[bdbits]

Good video, he usually does a nice job on any Sony topic. By the way - an important thing he mentioned I neglected to say was you also need to change the setting from Std+Range to Lower Limit for this purpose. Anyway, the FM thread has quite a discussion around the topic if one wishes to dig into it. They discuss several parameters that can particularly affect zebras, most notably the picture profile selected or if none is selected. Galer also pointed out this might vary with body, and mentioned he'd seen 107+ sometimes recommended. I think in the end you'd probably be best off picking either 107+ or 109+ as a starting point, and see what seems to work best with your own camera settings.

 

[John King]

Tim, most manufacturers play silly buggers with their tone curves.

Most shift the midpoint one direction or the other. Rolloffs also need to be watched. Ideally, the roll-off should never intersect the top or bottom of the sensor response, but gradually approach very close to both points.

Some cameras do intersect the maximum and minimum that the sensor can handle, and their files can be very tricky.

The trick is to work out what the manufacturer has done, and then compensate for it, as best you can, either in-camera or in PP.

 

[Brownie]

Good video, he usually does a nice job on any Sony topic. By the way - an important thing he mentioned I neglected to say was you also need to change the setting from Std+Range to Lower Limit for this purpose. Anyway, the FM thread has quite a discussion around the topic if one wishes to dig into it. They discuss several parameters that can particularly affect zebras, most notably the picture profile selected or if none is selected. Galer also pointed out this might vary with body, and mentioned he'd seen 107+ sometimes recommended. I think in the end you'd probably be best off picking either 107+ or 109+ as a starting point, and see what seems to work best with your own camera settings.

I honest to God can't stand listening to that guy, but I did suffer through this video. The first time I ever watched one from him in its entirety. It was mercifully short.

The biggest difference in the numbers he notes is between jpeg and RAW. The higher number was more suited to RAW. Note too that the picture profiles do not affect RAW as concluded by someone I do enjoy watching, Gerald Undone, so the picture profile would only have an effect in jpeg.

Not all that interested in zebras but I may give them a shot, biggest concern is learning to use them quickly, I'm so used to looking at the meter it's second nature. For the most part I've noticed 1/2 stop or less in post, so if that's the only issue I can just use exposure comp. The DR on these cameras is so wide I've really never had a problem recovering one end or the other when needed.

 

[Brian]

The Nikon FE had a sensor?

Yes. One that could be perpetually upgraded.