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Velk
08-03-2004, 10:06 PM
This is my first attempt at photorealism. The modeling, textureing and rendering took 4-5 hours. The image was created using 3ds Max 4.3 and Photoshop for slight adjustments in DOF post render (default scanline).

I would like comments on both the realism of the scene (lighting models etc...) as well as the textures used. Thanks in advance,

cg219
08-04-2004, 12:51 AM
THe candle and candle wicks looks pretty Photoreal, not completely, but a little. The candle holders look fake to me though. It could be the lighting. But thats all I see wrong with them.

hpslashluvr
08-04-2004, 01:05 AM
i think the candle could benefit from being just slightly more translucent, like just barely

i think the view isn't a good one tho, maybe see more of the top

Velk
08-04-2004, 02:37 AM
Yeah, the wick on the candle really needs to be a tad more, I don't know, waxyish. There isn't enough light coming through it or something.

CG219 what looks fake about them? is it the reflections or the shape or what?

Here is the top view as well, I didn't change the lighting scheme at all.

MattH
08-04-2004, 08:37 AM
The shadows look too crisp and uniform to me. Think about what kind of environment you want these candles to be placed in and go find some reference for the lighting and shadows.

pha3z
08-04-2004, 11:34 PM
ooo Focused Critiques for Velk!! :)

really good work for a first attempt! :) but here are my thoughts on why it doesn't look photo-realistic:

a) your candles appear to have no transluncey or not enough. Are you familiar with the concept of Sub-surface-scattering (SSS)? it happens when you shine a light through a material and the light boucnes around and scatters inside the material and comes out in various places (causing the material to sort of glow). If you were to render this in Brazil, there is a material specifically meant for what you're tyring to do called the Wax shader. It has all the SSS parameters you need :)

b) scanline renderer is just hard to use for photo-realistic work. :P

c) the metal could use some work. if you're using the "metal" shader that comes with max, i suggest you don't. change to another basic shader and then raytrace the reflections.

d) are there specular highlights on the candles? specular highlights are just a way of faking reflections from light sources. if you want photo-real, you probably shouldn't use specular highlights. you should be raytracing all your surfaces.

e) i think the tips of the candle wicks could use a little work. i would think they should be freyed a little bit at the ends (they're string with wax coating right?) *shrugs* up to you on that one.

you're doin good, though! keep it up :)

Velk
08-05-2004, 01:23 AM
Thanks pha3z for those useful comments. I am familiar with the concept of SSS, unfortunately I don't have Brazil to render with (though I've looked at Rio). I tried to fake it by using a slightly lowered opacity and a very low specular level with the difuse cranked up. I think it worked pretty well except around the edges where it isn't translucent enough.

The metal material is not the default material, it is one I created. I tend to stay away from the default materials, hard to get better if you only use the standereds (kinda like using a prebuilt sphere for a character head... :D).

The highlights on the candles are specular - I guess I need to raytrace everything to make this look more realistic, thanks.

The wicks I wanted to look brand new, so I left them encased in the wax. My wife has a set like this and I took the idea from them.

faulknermano
08-05-2004, 07:14 AM
hello velk, here's just my take on your images:

i'd like to judge photorealism by the environment as well as the subject that's in it. when i mean environment, i mean the lighting, the surrounding textures and physical atmosphere. i find your setting very sterile so it is hard to judge your work as photoreal.

however, i do like the matte-edness of your candles. the wick doesnt seem to be convincing however. the metal, is not very convincing either.. but mostly because of the environment you used (which was white). a good spherical photo reflection map will help in this respect. but i suggest taking as much time laboring over the environment as you did with your subject, because i think photorealism as more to do with their interaction with each other, as opposed to simply the subject's materials only.

just my opinion. :)

Velk
08-05-2004, 02:26 PM
Thanks for the insight faulknermano, I was trying for a studio type shot that might be found in a catalog or magazine. However I totally get what you are saying about the lack of depth because of the overwhelming whiteness of the image.

GH33DA
08-08-2004, 11:43 AM
d) are there specular highlights on the candles? specular highlights are just a way of faking reflections from light sources. if you want photo-real, you probably shouldn't use specular highlights. you should be raytracing all your surfaces.

I'm sorry to interrupt your thread like this Velk, but, I'm very curios on this piece of advice.

pha3z,
I always thought that specular highlights exist in real life, so I add them. Even my ray traced metal materials have a specular level. It's a high 250, with a gloss of about 80, but it's still there. Now, I'm all bummed cause I've been doing it wrong. :( So, is there ever a good time to use specular levels vs. and HDRI map in a photorealistic render?

Man, just when I think I'm getting the hang of this. I feel like a noob all over again...Way it goes.

faulknermano
08-08-2004, 11:46 AM
I'm sorry to interrupt your thread like this Velk, but, I'm very curios on this piece of advice.

pha3z,
I always thought that specular highlights exist in real life, so I add them.
spec is a cheat to simulate a reflected light source. in a sense they exist in real life, but they are, as a matter of fact, reflections, as opposed to simply "specular highlights." they're only highlights because the one being reflected is bright.

GH33DA
08-08-2004, 04:27 PM
So I should only use HDRI maps in my enviroments for photorealism?

faulknermano
08-08-2004, 04:34 PM
So I should only use HDRI maps in my enviroments for photorealism?
no, you shouldnt limit yourself. environmental photorealism can be, and has been acheived through "traditional" means. i like using HDR personally. but i usually correct the colors in post or add extra lights to get the look i want. i think even photorealism has a subjective aspect to it. just my opinion, though. :)

pha3z
08-09-2004, 03:30 AM
spec is a cheat to simulate a reflected light source.
Hey sorry i so GH33DA's question a bit late. Thank you, faulknermano, for answering him! This is exactly what i would have said! :)

And yes, photorealism does have a bit of subjectivitiy about it. :)

GH33DA, as far as ever using Specular highlights, yes there are times when it is appropriate. a) you can't afford the render time to raytrace everything so you fake some of it. b) you WANT things to have a Computer-generated feel about them and not quite look real. c) you come up with your own creative use.

HDRI maps are a way of setting up a realistically lighted environment without actually modeling the environment. Obviously, you don't need HDRI maps or any environment maps for that matter if you really build the environment :P. If you take a look at the glass fish in my scene, you can see some reflections of windows on the fish. I didn't model these windows as that would be a silly waste of time if i can just throw down an HDRI map real quick. ;)

Do what you need for each situation that comes up.

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