[iade360]

I think I've seen this discussed in previous posts in my short time on the forum but I can't seem to find them so my apologies if this has already been covered.

When doing product renders, is there a way to create a 'perfect' white floor revealing shadows only, but without post compositing ? For example, in 3Dmax you can create a matte/shadow material type to achieve this. Is a similar approach possible in Maxwell? The excellent Head & Shoulders and Loreal renders in Justin's gallery are a perfect example of what I'm trying to achieve with the 'white' floor: http://www.maxwellrender.com/forum/view ... hp?t=34562

At the moment I'm trying various white materials with limited success. Finding it difficult to illuminate consistently and getting the white 'white' enough without compromising the shadows.

I'm now using the HDR Lightstudio Plugin with Maxwell if that makes any difference.

Any suggestions or advice greatly appreciated.

Thanks!
Ian

[brodie_geers]

Out of curiosity, why don't you want to do any post processing?

-Brodie

[iade360]

Out of curiosity, why don't you want to do any post processing?

-Brodie

Good question and thanks for the reply. I guess because of habit, which isn't a good reason. I've always liked to try and keep everything within the rendering software and avoid the need to do anything post-render to an image. Although this isn't quite so valid with my white floor dilemma and presumably necessary and the way to go for best results? I'll read up on compositing in Maxwell and give it a go.

Thanks

[brodie_geers]

I would certainly recommend it in this case. I've not seen a good way to do what you're asking. The problem is that there aren't really any real world materials that are 255 white and if you plug that into maxwell you'll get a noisey result (which probably still won't come out at 255 white because of lighting and such). So, while I'm generally in favor of doing as much as possible through the render engine, you'll get what you're after much faster through post in this case (particularly since you're wanting a technically unrealistic result).

If a photographer were tasked with the same issue their solution would, no doubt, involve postwork as well, either with some sort of green screen compositing or using a white material and adjusting the levels in PS to make it 255 white.

-Brodie

[itsallgoode9]

brodie is correct. go with the post process. you'll save yourself days or weeks of tweaking time and end up with a better result. To give you an idea of what goes into a high end advertisement shot of a product shot of a liquor bottle (that is what I know, so that's why the example is that)...

One lighting setup for the cap
One lighting setup for the bottle and liquid
One lighting setup for the label (possibly two depending on if it has a face and footer label and where they are placed)
Possibly one lighting setup to make any embossed lettering or graphics on the glass pop out (getting highlights on top of the embossed pieces, etc)
One lighting setup for the reflection

combine all of those together in photoshop THEN hire a retoucher to finesse the lighting on everything...adjusting highlights, adding highlights, removing shadows, adding reflections, removing reflections etc.

Not every shot is exactly like this, but I can guarantee that no photographs for something like this are done in one shot. Embrace the post process. I would recommend googling some retouchers portfolios and once you see how different the raw image from the camera looks compared to the final image, after being retouched...you'll feel more comfortable with not feeling like you need to do it all in the render.

[iade360]

Thanks for sharing your approach Justin. Wow! In stark amateurish contrast back in my 3Dmax days I would set up a light for an object, exclude everything else from illumination and then set the light to specular just to bring out highlights on that part only –– I only used to use PS for adjusting levels or cropping and resizing images. Not any more though! I have taken on board Brodie's advice and spent the last few days working out how to use the alpha channel. I followed Jason's tutorial on the output channels and found Tom's helpful PS Action on the Think site which makes it super easy. This has now made me very curious as to how to utilise and work with the other output channels to enhance renders. It will be a while before I progress to advanced multi-lighting setups –– you must be a valued renderfarm customer with all that rendering!

Thanks!
Ian

P.S It would be nice to see some specific before and after examples in the WIP gallery that help to illustrate the power of postwork. It would also be an interesting challenge to provide a single set of output channels and see the variation in how everybody uses the source files to generate a final visual.

[brodie_geers]

I don't have any great before/after's handy but I typically don't use a ton of render passes. Maxwell offers quite a few (although even those are only a fraction of the passes Vray offers). I normally use alpha, material ID, and object ID for my exterior archviz work. Those last two passes make it really easy to make a selection of only the windows and make tweaks to just that area, or only the light beige stucco, etc.

-Brodie

[itsallgoode9]

on another note...you can use an AGS clear plastic material for reflections and it should give you your look. I have been doing that lately now that I come to think of it. Some instances that will work but sometimes it's just better to adjust in post process to make white.