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HDR tests

Posted: Thu Aug 24, 2017 4:32 am
by Mihai
I recently started creating my own HDR maps and here are tests with the first 3 of them. They have a very high dynamic range as you can see from the depth and sharpness of the shadows for the two sunlight ones. There is no post processing on these, I just used the "Agfacolor Futura 100" tone curve.

First one early in the day, so the sun is still pretty low and the sky is very blue - hence the blue in the shadows.

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Second one is later in the day so the sky is less blue and everything is warmer.
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Third one is the sun hidden behind a cliff so more diffused light.
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If you have some ideas of HDR maps you'd like to see or think there aren't enough of, please let me know. I also take real photos at the same time which can be used as backplates. I plan to recreate the camera positions in 3D, and create a ground plane with the texture from the location, so it will be easy to just put in your model, load the HDR and render. The full rez maps are 14000 x 7000 but I was thinking of giving smaller rez versions for free for anyone who purchased anything from the maxwellzone store. So well, not really free...lets say "complementary". Those would be without backplates but probably include the textured ground plane.

I take care to white balance them (leaning toward the strong sunlight when available, not the overall sky) and match the intensity of the sunlight/ambient using a grey sphere when taking the photos. The sun is also centered horizontally so it's easy to switch maps and have the shadows fall at the same angle.

Re: HDR tests

Posted: Thu Aug 24, 2017 9:18 am
by Hervé
Nice hdri Mihai... and nice car shading

Re: HDR tests

Posted: Thu Aug 24, 2017 5:02 pm
by Mihai
Merci Hervé!

Re: HDR tests

Posted: Thu Aug 24, 2017 5:53 pm
by rusteberg
I stare at the sun all the time so the third one is very appealing to me. Very nice :D

Re: HDR tests

Posted: Thu Aug 24, 2017 6:14 pm
by Rafal SLEK
Yes, for me the third one is also the best.

Re: HDR tests

Posted: Fri Aug 25, 2017 9:28 pm
by Mihai
Thanks for the feedback gents, interesting...

Here is a test with one of the photos, convincing or not? (you need to increase the width of the browser window to see it bigger)

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Re: HDR tests

Posted: Sun Aug 27, 2017 5:52 pm
by Eric Nixon 20170610100005
Scale looks very small, due to the enclosed nature of the space, if you map this hdr onto a low-poly scene geo it will look better. But light thru trees is kind of impossible without a really heavy scene.

Being picky, the Carbon fibre shader (its a tricky material) lacks a little bit of sparkle in the bright sun renders. I think I've had to build my own CF mxm about three times from scratch, with different maps until it looked real enough.

Re: HDR tests

Posted: Mon Aug 28, 2017 12:59 am
by Mihai
I'm not sure I understand the comment "scale looks very small"?

About the carbonfiber, yes it's just a material I found on the old MXM site which I thought had decent normal maps so I picked it. It does lack of bit of oompf I agree.

Re: HDR tests

Posted: Mon Aug 28, 2017 2:02 am
by Eric Nixon 20170610100005
The car looks very small if you ignore the background, like the trees its reflecting are very far away but very tall.

Re: HDR tests

Posted: Tue Aug 29, 2017 1:51 am
by Mihai
I did do a test with a 20m sphere around the car with the HDR applied to it but it didn't make that much of a difference...?

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Re: HDR tests

Posted: Tue Aug 29, 2017 4:56 pm
by Forum Moderator
Very nice Mihai!

FT.

Re: HDR tests

Posted: Wed Aug 30, 2017 12:15 pm
by choo-chee
Mihai wrote:
Thu Aug 24, 2017 4:32 am


If you have some ideas of HDR maps you'd like to see or think there aren't enough of, please let me know. I also take real photos at the same time which can be used as backplates. I plan to recreate the camera positions in 3D, and create a ground plane with the texture from the location, so it will be easy to just put in your model, load the HDR and render. The full rez maps are 14000 x 7000 but I was thinking of giving smaller rez versions for free for anyone who purchased anything from the maxwellzone store. So well, not really free...lets say "complementary". Those would be without backplates but probably include the textured ground plane.

I take care to white balance them (leaning toward the strong sunlight when available, not the overall sky) and match the intensity of the sunlight/ambient using a grey sphere when taking the photos. The sun is also centered horizontally so it's easy to switch maps and have the shadows fall at the same angle.
I'd like to see a real good HDR of a cityscape that is good for typical exteriors: not too big with tons of skyscrapers, and not too small with only 2 shops as a facade ....
very good renders !!!

Re: HDR tests

Posted: Wed Aug 30, 2017 5:30 pm
by Mihai
Thanks for the feedback - in your usage case does it matter that you have back plates to go with the HDR, or not so much?

Re: HDR tests

Posted: Wed Aug 30, 2017 5:57 pm
by rusteberg
I think backplates are very site/location specific - If it is a priority to show something on a specific backplate then you're most likely to shoot that yourself unless you're providing some sort of highly generic location that could pass for a car or something shown in either Atlanta or Amsterdam. I have quite a lot of Peter Guthries sky hdrs that I use a lot for archviz and I don't think I've ever used any of the backplates they come with.... More interested in a HDR that provides a well balanced lighting solution for a given object or scene and doesn't have some weird shit showing up in reflections... But that's just me :)

Re: HDR tests

Posted: Wed Aug 30, 2017 6:20 pm
by Mihai
I see, that makes sense :) I think I have a few neighborhoods pretty close by which would be suited for modern/urban and also provide at least some reflections of buildings so it doesn't look like it's in the middle of nowhere. It's the typical modern buildings your modernist-obsessed clients will adore (camembert triangles with holes in them, or amoeba shaped erections, that sort of stuff...)

I'll make a few and ask your opinions :)