back to basics- complete vis VRAY- WORKFLOW- LONG

[t3dm]

Hi all,

Just wanting to share a new project we are working on and some of the issues and indeed looking for conformation as to the workflow we are using and the issues I am seeing. ultimately its a workflow we have adopted since moving over to using hdri's (mainly our own, but do use other off the shelf hdri's too, Peter Guthrie's etc.. sometimes just plain old sun sky. I am finding it harder to keep all our assets with various legacy materials upto date. I am wondeing if our materials/colour space and final finishing are causing issues and looking for some comments on how we typically work. I am wanting to up our HDRI capturing game as well as our materials and virtual photography (exposures etc)

This project in particular starts with a site HDRI:

1. Nikon D7200 DX camera with 10.5mm nikkor lens, nodal ninja and Promote sytem for the exposures (9). Shooting raw aRGB
2. into lightroom for correction (convert to srgb and then export all images as 16bit tiffs srgb)
3. into photomatix to merge all exposures, and save as 32bit exr (zip)
4. stich and export as exr from stiching program (ptgui)

3DSMAX: focusing on lighting set up and gamma
1. We work in half LWF... so gamma set to 2.2, we output images as 16bit tiffs (colour mappin only mode in the colour mapping roll out selected)
2. photoshop for post work (not usually a lot)

See the attached image, which shows our set up and a WIP render, complete with HDRi (set at .78 gamma), the gray temporary material on the still to be modelled drive shows how we input colour, diffuse colour uses a vray color map (set to specify 2.2) so we can match up rgb values where we need to (though most things will be a srgb texture)

You can see our HDRI is not really matching that well at the moment, I will mange to get this looking better, its a challenging one taken with a very strong low winter sun. I really need to get back into colour profiling and calibration, but for a while we have just stuck to sRGB... mainly for simplicity.

Would like to discuss my workflow and see if there is room for improvement? In terms of describing black as a diffuse colour - I use a self imposed rule of around 30,30,30 in the vray colour map and pure white - no higher than 210, 210 ,210... again in the vray colour map.

[Macker]

Sounds like you're over-thinking/complicating a matter. If it looks good, it is good.

I'd be more concerned about the scale of those bricks, if I were you.

[t3dm]

haha! it's not finished! thanks though.. brickwork is only a test... will be made tileable, then unwrapped and then displaced...

the problem is real, I'm finding it hard to explain, but really I'm suppose I am trying to discuss my workflow, and seeing what people think... mainly from HDRI creation to then scene lighting and materal creation. Been looking at updating a lot of our materal shaders, to be more physically acurate and something that will need less 'fudging' depending on lighting, hdri type etc..

Got a ND filter for my 10.5mm lens so going to try and create some 'better' wider range HDRI's.

here is an inside render.. quick progressive test... white material is 198,200,201, exposure is ok, but I think again the HDRI is too punchy and warm compared to the interior.... obviously I can adjust, i'm not looking for a solution to that, jsut want to explore the workflow?

still cant fully articulate what I am getting at! sorry! I'll have a glass of red wine and come back!

[VelvetElvis]

What real world visual reference are you trying to re-create?

If you have no reference images to draw from, stop everything and go find some. You should never rely on just your brain's ability to recall that you think you'd see in a space to guide your overall look development.

For the image, you have a photo background versus a 100% gray interior. Of course there is going to be a vast difference between the two.

[squintnic]

looks ok to me
overcomplicating things imo
you can adjust in photshop after you render.

[squintnic]

i would also recommend using either cgskies or peter guthrie HDRIs rather than your own

[t3dm]

sorry.. not explaining myself.. Ill come back with a more clear post, perhaps a step by step process, as to how we work and see if others can comment on workflow. Just looking for a discussion on workflows and HDRI reference/capture... not overthinking.. this is visualisation

[Neilg]

sorry.. not explaining myself.. Ill come back with a more clear post, perhaps a step by step process, as to how we work and see if others can comment on workflow. Just looking for a discussion on workflows and HDRI reference/capture... not overthinking.. this is visualisation

At dbox we sometimes use sun/sky. sometimes we use a hdri we bought, sometimes we make one. sometimes the one we make is wrong - not enough range, or the range is skewed. sometimes we even use a jpg. sometimes we use 2 completely different hdri's that have no business being used together too. doesn't matter if it looks good though.
There is no step by step - first we figure out what we want to achieve, and then work backwards from there using any and every tool in max & vray to make it happen. You're too focused on a very rigid recreation of reality when every architectural photographer worth their salt would love the ability to mess around and do things 'wrong' for the sake of the image. If this is a question of learning how light works, go out with a camera instead.

[Sawyer]

My hunch is your workflow is appropriate and is getting you right where it should be. But seems like you have something specific you would like to be different - if thats the case update with an example of what you would like different. From what it sounds like you want a specific feel of the image which may be something you should look at in post.

[crazy homeless guy]

Do you have photo references of what you are trying to achieve? It sounds like you are trying to figure out a formula for producing perfect renderings but without a photo reference you are only aiming at an idea in your head that you feel is real.

I agree with the post(s) above about not overthinking your process.... You can have a basic workflow that you use as a starting point but every image will likely require adjustments to that workflow in order to achieve what is most successful for that image. These adjustments happen while working on the project.... While doing test renders and then comparing your result to a photo reference.

I would also be very cautious of stating that you that something is photoreal simply because you used an HDR. That is far from the truth... HDR can give you variation to your lighting but unless you have measured light intensity levels while shooting the HDR you are still using your judgment and experience on how bright things and how the light effects the scene.

It is also important to understand that Guthrie does not use a linear workflow. If you look at his test scenes he uses Reinhard set to 0.1 or something similar. That is essentially a logarithmic workflow. Which is essentially the workflow everyone used before people started to throw around the term linear workflow. In fact... I don't know a single person that uses true linear workflow.

Essentially... Reality is overrated. Render with your eyes and not your brain. React to what you see when you render and adjust accordingly rather than trying to come up with a rigid process.

[crazy homeless guy]

As far as your white levels... Vray needs an Albedo pass like Corona. Though the developers don't feel it is important so I wouldn't hold my breath.
http://forums.chaosgroup.com/showthr...ghlight=Albedo

[joconnell]

Albedo is diffuse filter? If you mean a levels check I bet we can do something like make you a LUT file that maps colours above and below a certain value to something really garish.

[Alan Iglesias]

...There is no step by step - first we figure out what we want to achieve, and then work backwards from there using any and every tool in max & vray to make it happen.

Very good advice here. Pretty much the way I do everything - in art and music.

...every architectural photographer worth their salt would love the ability to mess around and do things 'wrong' for the sake of the image...

And I'm sure I've I've said this exact thing to folks about a million times in the past 20 years...

Nice, Neil.

-Alan

[crazy homeless guy]

Albedo is diffuse filter? If you mean a levels check I bet we can do something like make you a LUT file that maps colours above and below a certain value to something really garish.

In Corona it is a render element. If it has red in it it means one of your colors, typically something like a white wall, is coming out overly bright and unatural. Just dial the intensity of the white back and all is good. Simple as cake.