[promacjoe]

There are several factors that Is involved when determining the dynamic range and general performance of a Camera. The sensor is just one determining factor. The amplifier that is used with the sensor plays a big part of the overall performance. in Both the noise and dynamic range. The Amplifier design is getting better with each new sensor. The amplifier should be profiled for that particular sensor but this is a difficult task electronically. The third factor in the dynamic range and noise is the software. the software interprets the signal and converts it, so that it can be Understood and displayed by the processor. in fact, the software can have more of an effect to the dynamic range than you might expect. it is easier to profile the software to get a better dynamic range and it is to profile the amplifier.

If the software is properly implemented, the dynamic range Should be close to if not equal, regardless of the sensor size.

Think of it like calibrating your monitor using software. Once calibrated, it has a better dynamic range Then a monitor that has not been calibrated.

in some cases, several camera manufacturers may use the same sensor. It is the software that determines the difference in dynamic range.
and in many cases, the difference in dynamic range can determine its niche in the marketplace. One camera may be better for landscape photography another maybe better for portrait and so on. what is the best dynamic range is determined by how it is used and the lens that you use with it for that particular shot.

[Kerrowdown]

Using your 30 year old lenses as they were intended to be used

That's good enough for me.

[jatrax]

That's good enough for me.

"Just because" was good enough for me but I didn't think that would be all that helpful...........

[Kerrowdown]

"Just because" was good enough for me but I didn't think that would be all that helpful...........

I'd have thought that was a fair stand alone comment.

[normhead]

If you look at all the Canon sensors, that never approached even K-5 DR, it's pretty hard to argue DR has much to do with pixels size. It's more about sensor design. Because Sony, Nikon and Pentax all use Sony sensors we tend to think as if all sensors were made with the same technology. There are other sensor makers out there. Most not as good as the Sony sensors for dynamic range.

[UncleVanya]

If you look at all the Canon sensors, that never approached even K-5 DR, it's pretty hard to argue DR has much to do with pixels size. It's more about sensor design. Because Sony, Nikon and Pentax all use Sony sensors we tend to think as if all sensors were made with the same technology. There are other sensor makers out there. Most not as good as the Sony sensors for dynamic range.

But then we would have to compare the large and small Canon's not the large Canon with the small Sony.

[Rondec]

Dynamic range is based on the size of your photon wells, from what I understand. The question is, I suppose, how efficiently your sensor captures the photons that are hitting it and how quickly it fills up. The D810 supposedly has the ability to shoot a lower iso due to having bigger photon wells. This allows it to have similar dynamic range at base iso (measure at iso 46, I think) as the 645z has at its base.

At the same iso, the 645z has better dynamic range than the D810, just like the K3 and the k5 actually have the same dynamic range from iso 100 on. It is just that the K5 can go down to iso 80 and the K3 can't.

My guess is that the K-1 will perform pretty much like the D800, maybe a little better, which is good enough for me.

[alamo5000]

I think I accidentally started a thread that will go to 20 pages LOL!

[JensE]

What Adam

If you took a 36-megapixel full-frame sensor like the one in the K-1 and compared it to a hypothetical latest-gen 16-megapixel APS-C sensor, the two should have roughly the same dynamic range. That would in turn be comparable to a 60-megapixel medium format sensor.

and jatrax

I would also expect that an APS-C sized sensor cut from the same wafer as the FF K-1 sensor would show identical performance regarding DR.

wrote seems to makes sense first, but there actually is an impact on sensor size with respect to (maximum) dynamic range if you look at a picture with a fixed output resolution.

Dynamic range on a sensor is, as both pointed out, largely a function of the individual pixel size. Assuming the same technology and, for simplicity, same processing, the maximum amount intensity of light is determined by how many electrons can be excited by light to be counted/measured after the exposure. This is roughly proportional to the individual pixel size. The minimum amount of light that can be captured is driven by how few electrons can be discriminated. If that (absolute) number is roughly constant for a given technology, i.e. if the A/D conversion is nearly perfect, then the minimum intensity of light that can be captured is is inversely proportional to the pixel area, i.e. twice as big would mean half the intensity is needed to excite that countable number of elecrons. The ratio between maximum and minimum determines dynamic range. Even though this is simplified to an ideal processing, as both formats are equally effected by imperfection, it shows that those theoretical limits are indeed only related to the size of the photo sites.

So where does sensor format come in? The deepest shadows that can be differentiated in an ideal sensor, and the recent Sony ones come fairly close, are determined by the noise that comes from the particle properties of light. I.e. low light intensity triggers a low countable number of electrons to be excited per photo site, resulting in variances between sites, seen as noise in deep shadows. Now if I have the same intensity of light on a small sensor as on a big, I have the same noise amplitude on both on a per pixel basis.

Say we compare a micro 4/3 sensor and a full frame sensor with same size of photo sites, for the same picture taken with them at same speed, angle of view and F-Stop, i.e. same intensity of light. Each pixel on 4/3 is then covered by 4 on the full-frame sensor. With respect to maximum intensity, they fare the same as discussed above. With respect to minimum on each photo cell they also do, BUT for the same output resolution, I can take the average of the 4 photo cells on the FF sensor. This means, random noise in the shadows roughly scales down by the square root of 4, i.e. a factor of two or one EV. Therefore, the larger sensor with the same size of photo sites, on the minimum intensity side, behaves similarly to a low-resolution sensor with the same number of pixels as our 4/3 sensor. Of the maximum side however obviously not, as the maximum is not a noise property but each photo site will have to be able to cope with the intensity without hitting the ceiling. So a high-resolution bigger sensor only scales on one end similar to a low-resolution big sensor, which improves on both ends.

I hope this gives a little bit of a feeling for the physical boundaries.

if I expose for the highlights but the rest of the frame is in deep shadow... how much is more... and how much more will be able to be recovered?

For APS-C K-5 vs. FF K-1 (roughly same pitch), scaling would be sqrt(sensor area ratio), which happens to be known as the crop factor and is 1.5. This is a bit ore than half an F-Stop of dynamic range improvement (0.58EV) due to sensor size. It is the same amount of sensor-size driven improvement as for low-light noise performance. Taken technology improvements into account, based on what we see from K-3, it may get close, but I would not expect a full EV of additional dynamic range.

[Tony Belding]

It's really a niche for those low MP FF cameras. Only the $6k+ cameras have them.

But as you say, they make crop mode mostly unusable. Perhaps Pentax will release such a beast, although I doubt it because their MF offering is already $6k. Hard to imagine them trying to sell an FF camera at nearly the same price point.

The Sony A7 II right now is selling around $1700 and I don't think it counts as a "niche" camera. That's a 24.3 MP sensor, substantially lower than the K-1. That's the type of sensor I was referring to, if APS-C crop mode wasn't a concern at all.

[normhead]

The Sony A7 II right now is selling around $1700 and I don't think it counts as a "niche" camera. That's a 24.3 MP sensor, substantially lower than the K-1.

Well, no, it's virtually the same price as a K-1 and with substantially less resolution.

[Tony Belding]

Well, no, it's virtually the same price as a K-1 and with substantially less resolution.

uhh.... Yes, that's exactly what I said. That was my point. Did I imply something different??

[normhead]

uhh.... Yes, that's exactly what I said. That was my point. Did I imply something different??

I have no idea what I read, but I'm pretty sure it isn't what you wrote.

---------- Post added 04-10-16 at 09:00 PM ----------

Dynamic range is based on the size of your photon wells, from what I understand. The question is, I suppose, how efficiently your sensor captures the photons that are hitting it and how quickly it fills up.

I've never been clear on how photon wells work. But I don't believe there's an actual well there that fills up with photons. That being true, (or false) I assume you're discussing capacitor like ability to hold a charge. If it's like capacitors you can have short little squat ones that use a lot of surface area, or you can have long skinny ones with the same capacity which take up very little surface area if stood on end. I'm not clear that occupying surface area translates to bigger "wells". Someone enlighten me.

If more dynamic range means bigger wells on DxO, how does a 16 MP K-5 show a DxO R mark of 14.1 MP while a Canon 6D scores 12.1? And a Canon 5D MarkIII scores 11.7.

It gets tiring seeing people repeat these things over and over again, when the exceptions are so obvious. people who use these kinds of simple analogies, don't know what's going on. I don't either, but at least I know I'm clueless.

[stevebrot]

Too early in the morning for popcorn, sadly. But his should be fun.

Yep...I did fire up the grill, though. I expect the total light crowd to be all over this.


Steve

[stevebrot]

recovery is latitude more than dr, but they are closely related... one difference is that you can't really measure latitude.

So, how does one measure dynamic range? Does someone have a universal debug harness to map the analog response for an exposure wedge?


Steve