Re-exposing an EXR image

[tricky]

Not sure if this should be in here or in Problems...

I have attached a WIP of an apartment we are working on. I have recently started rendering out EXR images which allow me to re-expose in 32bit space in Photoshop. However, this shot isn't working as expected.

Now obviously, I haven't got the balance of lighting right yet, but I thought: "Hey, I should be able to open this up in Pshop and re-expose so that the ceiling halogen lights look less blown out, cool!". However, when I do this, it doesn't expose as expected - if I under expose, it looks like I am using plain old levels on the image and all the blown out bits just fade to grey. I would have expected the blown out bits to remain as bright, but just shrink in size (if you know what I mean) so that I can bring more detail out of the paintings on the wall.

Am I thinking about this wrong?

Heres the exr image if you want to play:

http://www.blinkimage.com/downloads/PH_150000.zip

[re:FORM]

I have noticed the same problem with my exr's.... Maybe we're saving the clamped colour as EXR rather than the unclamped data.

[rivoli]

the image is clipped, did you have clamp output checked when you rendered it?

[tricky]

ah - perhaps. I'll try again. Thanks for suggestion

[vlado]

To get unclamped output to an .exr file in RC3, you need to use either of these methods:

1) render to a .vrimg file and then convert to .exr with vrimg2exr;
2) use the the "split render channels" option of the V-Ray VFB;
3) use the "save image" button in the V-Ray VFB;

If you just use an .exr file output in the Common tab of the Render Scene dialog, you will get a clamped .exr image. This is corrected for RC4.

Best regards,
Vlado

[rivoli]

1) render to a .vrimg file and then convert to .exr with vrimg2exr;
2) use the the "split render channels" option of the V-Ray VFB;

just tried to save both in .exr and .hdr format via the "save image" button in the frame buffer window, and that seems to work as well.

[vlado]

1) render to a .vrimg file and then convert to .exr with vrimg2exr;
2) use the the "split render channels" option of the V-Ray VFB;

just tried to save both in .exr and .hdr format via the "save image" button in the frame buffer window, and that seems to work as well.

Yes, this too... I'll add it to my post.

Best regards,
Vlado

[tricky]

render to a .vrimg file and then convert to .exr with vrimg2exr

Where is this utility?

[tricky]

...think I've found it

[tricky]

Does anyone have a working link to vrimg2exr?

[rivoli]

you'll find it in the vray directory: programs>chaos group>vray>tools>vrayimg to openexr converter

[tricky]

ah-ha. thanks