HDRI Help needed!!!!!!!

[Paul Welch]

Hi I have downloaded one of Peter Guthrie HDRI's, opened the EXR file and it looks incorrect (see image attached) nothing like Guthries preview image. I then opened the file in photoshop and messed around with the HDR toning and got the image to come through but it still looks incorrect! (see attached image). I can use HDRI's to light my scenes but am unfamiliar with the intricacies of actual HDRI images!! Can anybody explain how I get the Downloaded HDRI to work to make it look like Guthries preview image?

 

Any help would be really appreciated as this is wrecking my head! Please look at attached image.

 

Thankyou

[Dave Buckley]

never had a problem with those hdr's.

 

but then again I never examined it, I just attached to a skylight combined with daylight system and it works like you'd expect.

 

Have you tried lighting a scene with it yet?

[Paul Welch]

Hi Dave

I have tried it using a vray dome light and it did not work at all in its original format. After playing around with it in photoshop and getting the actual image to come through I got some decent results but it is still not right as you can see from the images.

Im not happy about it because I paid for it and cannot figure out why it looks the way it does!

I know the hdris are spherical and blacked out at the bottom because that is the ground plane. I have a few other HDRI that I use and this one looks nothing like them!!!!

Frustrating as I do not know what to do at all to correct the image. I even messaged Peter Guthrie but havent heard anything back.

If you have any of his HDRI how do they look in their original format?

Cheers

Paul

[Dave Buckley]

Strange

 

As I say I've never had problems.

 

Peter will no doubt get back to you when he gets a minute.

 

I know he's pretty busy these days and he generally does get back to poepl especially when it's regarding issues with his goods.

 

Have you had a read through the comments about his HDRI setup on his blog, theres a good 60+ comments discussing them which may provide you with your answer

[Paul Welch]

Yes I did read through the comments but there was nothing useful.

I can still get decent results with the hdri I manipulate in photoshop but I want to sort it out so work can buy me some packs of Peters HDRI's.

I just do not know why the HDRI looks like it does I opened it straight away from download and havent touched it at all. Could be something really simple I am not doing or there could actually be a fault. Typical! I might just pay for another one and see how that comes through.

Thanks Dave

[Stephen Thomas]

From the look of it, there is nothing wrong with the exr file. It is a high dynamic range image i.e. the colour values are too widespread to be shown on a display screen. The image shown on Peter's link is a tonemapped version of the HDR image, and the problem it seems you are having is that you are not able to create a similar matching image to use as a backplate, rather than there being an issue with the exr file itself. Perhaps you are used to looking at HDRs/EXRs with a relatively low dynamic range, I know Peter's have a higher range than most.

 

Try converting to 8-bit mode using Exposure and Gamma rather than Local Adaption and you will probably get good results. Local Adaption requires editing of the curve to get decent results and is tricky to use.

 

The whole point of Peter's sets is that the exr file is for lighting and reflections, the accompanying backplates are supposed to be used for the background in the image.

[peterguthrie]

Hi Paul, I always reply to emails, in your case i was a bit slow though as i have been really busy, sorry.

 

In photoshop, just drag the 32bit exposure slider up and down to see the full range (its on the bottom left of the image window.)

 

in 3dsmax, it should work fine with a vrayphysicalcamera, but if using a normal camera you might need to adjust the multiplier to something pretty low (0.1, or 0.01 maybe?, its been years since i used a normal camera!)