[biz-engineer]

DR (dynamic range) is often confused with noise level, and that is due to the definition that has been given by camera sensor test labs (DXO etc) for marketing purpose. In practice, I get more useful dynamic range if I under-expose as much as it is required until highlights aren't clipped. Also practically, 8 stops of exposure latitude is more than enough because human eyes are much less sensitive to details in zone I & II of the zone system (near black and deep shadows). What matter in a photograph is that the key subject elements of an image receive more light than other parts of the photograph so that to lead the eyes on what's important. Noise and details in shadows play a much smaller role in making photographs an impact, that's why I say that the lab definition of dynamic range is mostly relevant to sell cameras. Typically, if your subject matter is in shadows and what's non-subject is in the light, no camera in the world will be able to correct for that bad configuration. OTOH, if the subject is lit properly and the rest is in shadows, 6 stops DR is enough.

[Rondec]

For current Pentax cameras the maximum DR is at iso 100. The K-5 offered iso 80, but the dynamic range was actually a little better there than at iso 100. The Kx had a base iso of 200 but was expandable to iso 100.

I think many high end cameras from other brands offer expanded low iso options. So, I think the base iso of the D850 is 64, but you can expand it to iso 32. It won't provide more DR at iso 32, but it will allow a longer shutter speed in a bright light situation.

[UncleVanya]

That's a read for my second coffee, I am still only on my first. Thanks Vanya

Be sure to read the explanations and methods also. They use user testing rather than testing in a central location there’s some degree of skepticism over their use of user monitors as the source of the images they have the people photograph but the data does track well against DXOMARK data (and there’s an explanation of the differences). I personally find it a fun way to look at this data but I’m not convinced it matters that much to me as I rarely find I’m struggling with dynamic range using cameras that are older and have small sensors and reduced dynamic range.

---------- Post added 12-11-21 at 08:34 AM ----------

DR (dynamic range) is often confused with noise level, and that is due to the definition that has been given by camera sensor test labs (DXO etc) for marketing purpose. In practice, I get more useful dynamic range if I under-expose as much as it is required until highlights aren't clipped. Also practically, 8 stops of exposure latitude is more than enough because human eyes are much less sensitive to details in zone I & II of the zone system (near black and deep shadows). What matter in a photograph is that the key subject elements of an image receive more light than other parts of the photograph so that to lead the eyes on what's important. Noise and details in shadows play a much smaller role in making photographs an impact, that's why I say that the lab definition of dynamic range is mostly relevant to sell cameras. Typically, if your subject matter is in shadows and what's non-subject is in the light, no camera in the world will be able to correct for that bad configuration. OTOH, if the subject is lit properly and the rest is in shadows, 6 stops DR is enough.

This tracks with my experience also. The k100d struggled with iso 800, the k-3 I could push to 3200 but 1600 was better, The KP and the Sony A7Riii are fine at 6400. Looking at my GX8 it scores slightly higher than the K-3 (original model) and the RX100IV has better dynamic range than the k100d at all iso values. This tracks well with me as I have good images from all of these cameras at around the 6.25-6.5 dr range measured. Bear in mind this data is photographic dynamic range and reports lower than the range DXOMARK claims for technical reasons that are discussed on the site.

Important to note is that the iso values in the photographic dynamic range test are those reported by the cameras settings and are not measured so inaccuracy in reporting iso (I’m looking at you Nikon) skews the results a little.

[texandrews]

Go to this website.

https://www.photonstophotos.net/

You will see the actual measured dynamic range and in that data you will see at which iso the dual iso sensors are best at.

FYI, not all experts have agreed with his analyses.

[UncleVanya]

FYI, not all experts have agreed with his analyses.

Which I understand. But I also don’t buy DXOMARK at face value.

[texandrews]

Which I understand. But I also don’t buy DXOMARK at face value.

Me neither! I just don't understand why there can't be a decent, objective review site. The only people I trust are Jim Kasson and Roger Ciala. I did used to like this other site, I think out of Poland(?)---can't remember the name off the top of my head....

[Mikesul]

Money and time make such endeavors hard. Oh, and dedication.

[UncleVanya]

Me neither! I just don't understand why there can't be a decent, objective review site. The only people I trust are Jim Kasson and Roger Ciala. I did used to like this other site, I think out of Poland(?)---can't remember the name off the top of my head....

I trust the motives of photons to photos. But the method may have some holes. Honestly the biggest cause for concern is over using data to make buying decisions. For example the em1-mk II shows as better than the em1-mkiii on the PDR chart. But most evaluations I’ve read don’t find discernible differences in those cameras optically. However I can’t compare the two directly so I can’t really say if that’s rational or not.

Lensrentals I trust - they clearly have zero sales bias. They want you to trust them and they get benefits in goodwill and in equipment validation but they are neutral on what gear that you rent.

[stevebrot]

DR (dynamic range) is often confused with noise level, and that is due to the definition that has been given by camera sensor test labs (DXO etc) for marketing purpose. In practice, I get more useful dynamic range if I under-expose as much as it is required until highlights aren't clipped. Also practically, 8 stops of exposure latitude is more than enough because human eyes are much less sensitive to details in zone I & II of the zone system (near black and deep shadows). What matter in a photograph is that the key subject elements of an image receive more light than other parts of the photograph so that to lead the eyes on what's important. Noise and details in shadows play a much smaller role in making photographs an impact, that's why I say that the lab definition of dynamic range is mostly relevant to sell cameras. Typically, if your subject matter is in shadows and what's non-subject is in the light, no camera in the world will be able to correct for that bad configuration. OTOH, if the subject is lit properly and the rest is in shadows, 6 stops DR is enough.

Thanks for this post. You saved me the trouble of doing so!


Steve

[texandrews]

I trust the motives of photons to photos. But the method may have some holes. Honestly the biggest cause for concern is over using data to make buying decisions. For example the em1-mk II shows as better than the em1-mkiii on the PDR chart. But most evaluations I’ve read don’t find discernible differences in those cameras optically. However I can’t compare the two directly so I can’t really say if that’s rational or not.

Lensrentals I trust - they clearly have zero sales bias. They want you to trust them and they get benefits in goodwill and in equipment validation but they are neutral on what gear that you rent.

Generally, I don't ascribe problems to motives, but rather to unconscious bias, which in its way is more pernicious because typically the biased truly don't believe they are, and will vigorously fight the idea that bias is even possible in their case. I hate to bring it up, but a very clear example is CRT today, and another is how women have been discriminated against in science. And engineering, pertinent here.

[kiwi_jono]

Pentax cameras normally have the best DR and minimum ISO and so on K-1 / K-P it will be best at ISO 100.
Certainly even on my K-x, I could clearly demonstrate the difference between ISO 100 and 200 - even on a sunny day (deep blue skies). The only Pentax camera, I'm aware of, that I'm not sure about in a practical sense is the K-5 with its extended ISO 80 - from memory thats starting to compromise highlights a little bit, although its extending range into the shadows (in fact I seem to remember DXO showing that ISO 80 it did give a little bit more DR overall).

[GUB]

Also practically, 8 stops of exposure latitude is more than enough because human eyes are much less sensitive to details in zone I & II of the zone system (near black and deep shadows). What matter in a photograph is that the key subject elements of an image receive more light than other parts of the photograph so that to lead the eyes on what's important. Noise and details in shadows play a much smaller role in making photographs an impact, that's why I say that the lab definition of dynamic range is mostly relevant to sell cameras. Typically, if your subject matter is in shadows and what's non-subject is in the light, no camera in the world will be able to correct for that bad configuration. OTOH, if the subject is lit properly and the rest is in shadows, 6 stops DR is enough.

How you utilise this DR is a bit different from just slapping it on the screen and "6 stops is enough"
I did a bit of a test for myself to try and think it through.
I took a series of photos of a blank surface achieving sequentially 15 stops of exposure. All at base iso - utilising shutter and aperture alone.
I opened the raws in the Gimp/Darktable plugin and exported them into Gimp unchanged.
I cut/pasted sections to create the first swatch.
And sampled and captioned the RGB for each exposure.
As you can see Gimp failed to register any colour for the last three and my monitor can see about 9 steps.
So I then took the curves tool and selectively brighten the dark end with a simple curve. And all the steps were there - even the 0.0.0 ones.
It was difficult to know when taking the shots when I was exactly at 100% white and this has potentially given me an extra half stop or so in this swatch. But it is fair to say I have recorded over 14 stops of DR.
The important thing is though, I have successfully taken those 14 stops and displayed them visually on a 9 stop monitor.
Agreed the 14 stop camera is recording a DR beyond what our eyes are comfortable with but we are able to convert it into a human friendly 9 stops and would be creating detail that a 9 stop camera would never create.
[IMG][/IMG]

[Alex645]

I was reading an article in Amateur Photographer in which the author referred to native iso. He stated that the native iso wasn't necessarily the base iso, but it was the point at which there is the least detriment to dynamic range. It is possible the author is being overly picky and 100iso is the gold standard, but I won't know for sure unless I ask the people I trust

I agree that the author is splitting hairs when comparing DR of the base and the native ISO. Older sensors would use 200 ISO as the native ISO, but your KP and most modern sensors is 100 ISO.

What makes a much bigger difference in capturing details in the highlights and the shadows would include a gradient filter and/or bracketing exposures for HDR.

[UncleVanya]

Generally, I don't ascribe problems to motives, but rather to unconscious bias, which in its way is more pernicious because typically the biased truly don't believe they are, and will vigorously fight the idea that bias is even possible in their case. I hate to bring it up, but a very clear example is CRT today, and another is how women have been discriminated against in science. And engineering, pertinent here.

You make a great and important point. Unconscious bias is a very real issue.

[Ian Stuart Forsyth]

I think the base iso of the D850 is 64, but you can expand it to iso 32. It won't provide more DR at iso 32, but it will allow a longer shutter speed in a bright light situation.

This is kind of right and wrong at the same time
With Nikon cameras like the D810 and the D850 you can expand the iso down lower than iso 64, If you are ETTR at iso 64 you are basically shooting at a lower iso and with the headroom allotted the user you can do this and when you are able to ETTR your are given more DR

---------- Post added 12-11-2021 at 09:20 PM ----------

I was reading an article in Amateur Photographer in which the author referred to native iso. He stated that the native iso wasn't necessarily the base iso, but it was the point at which there is the least detriment to dynamic range.

One of the more important things to remember for DR it really boils down to the largest exposure you can get for your images, If you are using the same size exposure over the different iso settings you are really not going to see much of a difference in the captured DR in your images ( with some cameras you might see a difference)

If you are shooting your camera at iso 100 or iso 1600 and neither you are overexposing your image you will capture the same DR. Take for example setting your camera to iso 100 while using EC-1 you might as well being using iso 200.

With some cameras as you increase the iso the camera produces less noise so if you are limited to light and need to increase your iso doing so with these cameras will increase your DR for the size of that limited exposure.