The Retro

[MattWBradbury]

An EXR image is a high dynamic range image. We created several maps with different intensities using a flate white surface and a sun light aimmed directly at the surface. We created 100%, 200%, 300%, 400%, and 500% brightness decals. They were rendered using the EXR file format in the rendering window. The EXR was then loaded into A:M and used as a decal on a surface. So whenever objects would reflect this decal, the reflection would be brighter than if you were to use a patch that had 100% ambiance. The eaisest thing (if they ever implement it into A:M) would be the ability to increase the Ambiance Intensity beyond 100%.

[ypoissant]

So whenever objects would reflect this decal, the reflection would be brighter than if you were to use a patch that had 100% ambiance. The eaisest thing (if they ever implement it into A:M) would be the ability to increase the Ambiance Intensity beyond 100%.

I don't think increasing ambiance intensity beyond 100% would give the results you expect. You could get the same result with a normal low dynamic range decal onto which you shine a very bright light. But that would not give the expected results because increasing ambiance intensity is like increasing exposure or increasing uniform light: every shades in the decal gets increased proportionately. You still have the same set of shades but more spaced apart. That would be usefull only if the decal color is a flat uniform shade which is a very limited application.

 

High Dynamic Range works for reflections because it contains all the low dynamic range data plus high dynamic range data where it counts. So you get normal colored environment reflections in the paint but also bright white reflections where it counts, that is where there are bright lights in the environment. That is the reason why photography works. It is because most of the lights in our living environment is of low dynamic range nature. There are only spots of higher dynamic range lights, most notably, the sky, which in a photograph will get cliped to white.

[Mr. C]

Wow, this is awsome!

[HomeSlice]

Thanks for the great explanations Matt and Yves.

[DanCBradbury]

There are only spots of higher dynamic range lights, most notably, the sky, which in a photograph will get cliped to white.

 

exactly.

 

My brother was taking pictures of our physics lab one day, and he decided to take the same exposure and f-stop values that he was using for one shot and took them for an outside shot; it was amazing how very different the light intensities were from the two environments.

 

 

I believe there's the equivalent of 13 one hundred watt bulbs shinning down on every square meter of ground outside just from the sun alone

 

tone mapping with hdr compression is really going to revolutionize photography

[ypoissant]

tone mapping with hdr compression is really going to revolutionize photography

I agree. But boy are the camera manufacturers slow at embracing that technology. HDR digital photography can be done with existing CCDs but a different way to handle the CCD must be coded. But no need to develop new CCDs basically (although it would certainly help HDR photography evolution). Just need to change the way the CCDs are controled and the software that controls them. HDR photographers do HDR photos using the technique of auto-braketing but they have to combine the single exposures into one single HDR image in an outside application which could easily be done inside the camera.

 

I know that the EXR team is actively lobbying the camera indiustry in adopting OpenEXR and embedding the library inside cameras but even JPEG-2000 can handle HDR data.

 

Anyway, I've been waiting for about two years, now, for a good HDR camera. Still waiting. Instead of going that way, they just add more and more pixels. What's the use of a 12 megappixels LDR image?

[DanCBradbury]

that would be great if you could get an inexpensive camera that took hdr or exr images, but the market for them just wouldn't be that great i dont think. It seems like most people just want a simple point and click camera and good pictures. They wouldn't really want to hastle with exr or hdr formats, so then the camera would probably have to come up with some way to do compression at the time of the picture to convert it to the robust jpg format that everyone is familier with, but then you would loos all that exposure data.

 

but yeah, if they could give you the option of making hdr or exr photographs, that would be awesome

[BrainLock]

What's the use of a 12 megappixels LDR image?

 

Larger prints and cropping.

[MattWBradbury]

The thing I find most concerning about HDR is the time that it's been in development. The first examples of HDR were in the 80's and they still have not implemented it in cameras. I think it's because it's easier for Studios to take a real scene and light it like a CG scene. Most of the film taken is with green screen anyway.

[goodguy20k]

I just fell across this article while looking for something else. Sounds... Familiar. Maybe with Microsoft behind it, camera manufactures will start movin' over.

 

And then of course, we'll hack all our cameras to use EXR instead.