The cameraville did it again

Started 11 months ago | Discussions thread
Ian Stuart Forsyth
Ian Stuart Forsyth Veteran Member • Posts: 3,376
Re: The cameraville did it again
1

Roland Karlsson wrote:

Ian Stuart Forsyth wrote:

Roland Karlsson wrote:

Ian Stuart Forsyth wrote:

The highlight that are clipped are in the jpg output image, in raw it is very unlikely that there was any clipping. As it should be the highlights are clipped because the brightness level output for Nikon was higher.

Hmmmm ... was it so?

He specifically told the listers not to bother him with JPEG.

Without having access to his raw files we will never know if any of the data is clipped.

But from understanding how Nikon and Pentax go about managing how their cameras meter we can guess as to if the images would contain any clipped data in the raw file

Here is what the D810 raw file look like when using the camera metering system, as you can see from the raw histogram we are far from clipping any data.

With the K1 we can see that for the same iso pentax is shifted closer to the right with less headroom than the D810 but still shows no clipping as it should as it is using a larger exposure

again we can see the same here

using the cameras meter we are far from clipping any data in the raw file.

with pentax you again see a shift to the right

How much headroom does the Nikon have and how much more EC is need to place the raw data to the clipping point closer to pentax

We can find out by applying ec+1 to the Nikon

So here ec +1 is added to the Nikon raw file and this now falls inline with how pentax and how close pentax clips in raw.

So even if he applied ec+1 I have my doubts that the Nikon would show anymore clipping to that of what pentax would.

If he want to use the same exposure for both pentax and Nikon he has to use a different output brightness for the Nikon as they use a different output.

Now if he insists on using the same exposure he must use and install a custom picture control into the D850 that would override what Nikon is doing.

OK - I am a bit tired. It is past midnight here in Sweden.

But - let me try to summarize what you say so we are sure I understand.

  1. Nikon's exposure meter chooses a lower exposure than Pentax. This creates a bigger headroom, and really protects against over exposure.
  2. Nikon compensates for the lower exposure by lifting up the processed (e.g. OOC JPEG)
  3. If then you use manual exposure and choose the same exposure for Pentax and Nikon, then the Nikon JPEG will be blown easier.

OK - if that is what you are saying, yes it is true.

But - I then still wonder what the guy is doing. Is he not supposed to understand such things? Having all those cameras, doing all those tests?

If we take a look at the information that he presents with the iso 6400 shots he is using the same exposure of 1/5sec f14, so are we surprised that the Nikon camera shows blown highlight in output image?

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/Roland
Kalpanika X3F tools:
https://github.com/kalpanika/x3f

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The Camera is only a tool, photography is deciding how to use it.
The hardest part about capturing wildlife is not the photographing portion; it’s getting them to sign a model release

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