[Murphy2004]

Hi

Can someone please explain to me the benefits of using the High Dynamic Range on the K20D. I see the ISO starts at 200 when used.

When do people use it ?

Do you use it all the time ?

Thanks

Jason

[lunelson]

I wondered the same thing, specifically whether it affects raw files also.

[navcom]

Hi

Can someone please explain to me the benefits of using the High Dynamic Range on the K20D. I see the ISO starts at 200 when used.

When do people use it ?

Do you use it all the time ?

Thanks

Jason

I own a K10D not a 20, so I'm not familiar with the ins and outs of the function on the K20D. I use my K10D to do the same thing though. On the K10D, I believe it only works with JPEG's but don't quote me on that. HDR refers to combining 2 or more images into one to compensate for exposure range limitations. On the K10D you use the multi-exposure mode which is a menu pick.

An example would be attempting to take a landscape photo during a bright day. If you meter for the bright and sunny part of your image, the shadows will disappear. If you meter for the shadows, the bright parts will be overexposed. With HDR images, you take one of each (or more) and then combine them to have a higher dynamic exposure range, thus the name.

It's a great tool and alot of fun!

Here's another thread with some helpful info along the same lines as your question....https://www.pentaxforums.com/forums/pentax-dslr-discussion/39810-k20d-hdr.htm...+dynamic+range

[kenyee]

It's not HDR because it only needs one frame. I think the Nikon D80 started it. I think what it does underneath is it tries to lift the shadows and prevent highlights from blowing out by scaling the data going into the RAW/JPEG files.

Take a few photos outside w/ parts of your photo in shadow and some in bright sunlight and turn it on and off...

[DAZ]

It has been discussed is some detail. The following links may be of some help.

https://www.pentaxforums.com/forums/pentax-dslr-discussion/26494-k20d-expanded-dynamic-range-opinions.html

https://www.pentaxforums.com/forums/pentax-dslr-discussion/22265-what-difference-does-d-range-200-really-make.html

https://www.pentaxforums.com/forums/pentax-news-rumors/19149-k20d-dynamic-range-enlargement.html

https://www.pentaxforums.com/forums/pentax-dslr-discussion/23787-k20d-dynamic-range.html

https://www.pentaxforums.com/forums/pentax-dslr-discussion/23917-k20d-expanded-dynamic-rage-test-request.html

https://www.pentaxforums.com/forums/pentax-dslr-discussion/23346-k20d-d-range-vs-100-iso.html

DAZ

[navcom]

Another point to remember about HDR....you can achieve much of the same effect if you increase the shadow brightness on an underexposed image using Photoshop.

[Marc Sabatella]

I own a K10D not a 20, so I'm not familiar with the ins and outs of the function on the K20D. I use my K10D to do the same thing though. On the K10D, I believe it only works with JPEG's but don't quote me on that. HDR refers to combining 2 or more images into one to compensate for exposure range limitations. On the K10D you use the multi-exposure mode which is a menu pick.

Totally different than the K20/K200D D-range function. All this does is shoot a single picture at an exposure that preserves highlights, then applies some sort of curves in internal processing to raise shadow levels (or something that achieves the same effect). In other words, nothing you couldn't do just as easily in PP.

[Murphy2004]

Totally different than the K20/K200D D-range function. All this does is shoot a single picture at an exposure that preserves highlights, then applies some sort of curves in internal processing to raise shadow levels (or something that achieves the same effect). In other words, nothing you couldn't do just as easily in PP.

Thanks for the answers and links.

So I take it most people don't use it and just adjust in PP ?

Is there any disadvantage while using it ?

Jason

[DAZ]

Two things get talked about on the K20D regarding high dynamic range. The first is the HD filter. This is just a digital filter like the other digital filters. It will give a look like HD but like the other filters is just for looks. Have fun with them or not. Up to you. The other is D-range. This is something different.

If you read the links you will see that basically know one knows really what D-range is doing. Pentax knows but they are not talking. If Pentax would just release a white paper so many questions would be answered. I have looked all over the Internet and the closest I have seen to a scientific test of D-range is the test on DPR. The test did show a 100% increase in DR. One stop increase in is twice as much light. This is only a single test point and I take it with a grain of salt.

The problem with looking at the DR in D-range is three parts:

1) If you take a photo of something and you don’t exceed the DR of the camera you are not going to see any differents. If the photo you take is not at one end all black and the other end all white (clipping) how are you going to see anything just by going to D-range?

2) When the photo is getting close to the edge of the DR most don’t know what to look for to see it. When they look they look to see if the shadows are brighter, this is not where to look. They are not looking to see if the are getting a color shift from clipping a color channel.


3) It is much harder to measure DR then most people think. For example DPR measures the DR of a camera and DXO measures the DR and they get 2 different numbers. DXO measures the DR of the K20D and the GX-20 that are almost the same camera with the same sensor and get 2 different numbers.

There are two thoughts as to what D-range is doing.

The first is that all D-range is doing is a curve to the file and that you could do the same thing PP.

In my opinion (and I can’t prove this it is just my opinion) this is not what the camera is doing. If all it was doing is a curve change it would not have to limit the D-range to ISO 200 and up. I think the camera is using 2 programmable amplifiers (i.e. 100 ISO and 200 ISO) and a 14 bit (instead of 12 bit) ADC.

I do use D-range when I think I may end up clipping a channel and need the DR. The down side to D-range is you get a little more noise. If you have a photo with a lot of DR then the small noise increase is in the dark parts. The dark parts will have very little detail so if you need to use some noise reduction on them not much is lost. This is relative easy to do compared to clipping a channel. If you clip a channel it is much harder (if you can at all) to recover PP and much more destructive to the photo then a little noise in the dark parts. If you are taking a photo and just about all of it is dark then this is probably not a high DR photo so you probably should not use D-range.

Having said the last I have use D-range on some night shots and firework shots to help keep the colors from turning white. I have had some good results this way.

By the way a one-stop increase in DR as about what you get going from APS-C to FF.

DAZ

[Marc Sabatella]

So I take it most people don't use it and just adjust in PP ?

I can't speak for most, but I don't use it, and it doesn't get discussed much, so I'm probably not alone.

Is there any disadvantage while using it ?

Same one that comes along with underexposing a shot and then pushing the shadow levels in PP: more noise.

Also, since it works only in JPEG, if you shoot RAW + JPEG, your RAW and JPEG files won't close close to matching.

[DAZ]

D-range works on both RAW and JPG.

DAZ

[Marc Sabatella]

D-range works on both RAW and JPG.

In what sense? Are you saying it actually affects the RAW data in a way that any RAW converter would be able to see? Do you have proof of this? Or is it merely that the Pentax RAW converter happens to be able to mimic the behavior of the in-camera JPEG processing to yield the same effect?

[DAZ]

Whatever the camera is doing it is doing to the RAW file. The RAW file is used to make the JPG. Even if the camera is only saving a JPG it still starts with a RAW file it just is not saving the RAW file. There is still the question of what the camera is doing to the RAW file. The effect can be seen with both the in camera JPG conversion and PP JPG conversion. We are only talking 1 more stop of DR so the effect can be hard to see but if you look you can see it. In the links are some photos that show it.

DAZ

[kenyee]

Are you saying it actually affects the RAW data in a way that any RAW converter would be able to see?

AFAIK, it's stated in the manual that it affects RAW files.
And FWIW, on the D80/D90, it also affects RAW files...

[Marc Sabatella]

And FWIW, on the D80/D90, it also affects RAW files...

Now, that much I am almost positive is not true - in fact, it's what made me suspect it wouldn't be true of Pentax as well. If you take a "D-lighting" shot in RAW and send it to a RAW processing program that doesn't understand how to re-create the in-camera JPEG processing, all you get is an underexposed picture. Well, I guess if that's what you mean by "affecting" the RAW file, then it is true that D-lighting "affects" the picture. The function does two thing with RAW - underexposes the shot, and then applies curves. Only the former is done with RAW.