Suggestions for more realism on motorbike composite

#1

Hi

I don't have a lot of compositing experience.
Any suggestions for making the bike fit into the background better.

It still looks to me like a sticker of a bike stuck onto a photo rather than a bike actually in the photo.
I’m pretty pleased with the shadow, (I was helped by Creeto and Silvercity from this forum).
I would prefer the tyre rubber to stay darker than the bike in the background’s tyre.
Is the chrome on the bike glowing a bit much?
Rendered in Maxwell composited in photoshop cs4.

Cheers

P.S. I tried to change the title of the thread, but it only changed the title of this post.

[img]http://www.craighood.com/aye%20040editshadow3.png[/img]

More (amateur) renders at [Craig Hood KZX](http://www.craighood.com/KZX.html)
#2

first thing that pops out to me is the blacks seem to black for the scene.

#3

Hi Scrawford

I thought that myself.
What’s the best way to lighten the black without affecting the other colours?

#4

Wow. Did I just answer that before you asked it?
Must be this coffee.

#5

Reduced the black on the bike and both tyres around 7% using selective colour,
Is this better?

#6

The blacks of the shadows (as the guy above corrected), also the reflection is a bit too saturated. The shadows lack color bleeding from the sky. And some cg elements look too sharp, the edges should be blurred with care.

#7

Hi Mister3d

Thanks for taking the time to analyse the image.
Do you think the blacks are ok now?
I noticed if I use an eye dropper on the bluest blue of the model’s rear wheel and compare it to the bluest blue of the exhuast in the background bike, they are almost identical, so if I de-saturate the reflection those colours won’t match anymore.
Should I de-saturate the reflection, but not the blue?
What do you mean by color bleeding in the shadows and how do I add it?
Also, is it possible for you to circle the edges you think need blurred and pm it or add it to this thread?

Cheers

#8

blacks need less black and more blue. as does the shadow. also the shadow is a bit too uniform in a non gradient way as in its too flat and doesnt ease into darker colors.

#9

also your chrome is turned up way too high and its too perfect. third, why is your wheel reflecting sunlight from under the engine when its supposed to be in the shadow (of the engine) instead?

#10

I think they are ok in terms of brightness. In the most saturated areas of your reflections the blue colors are visually more saturated than in the plate reflection. You should desaturate the color of the reflection, i.e the blue. Desaturating cg elements usually is more beneficial than making them saturated as it helps to integrate it better. Color bleeding is a diffuse reflection, in this case it’s the blueish tint of the sky… though maybe it’s not a color bleeding, as color bleeding is a reflection, and the blue tins is a direct color tinting.
Photoshop is not the best program for compositing, maybe try fusion or nuke? Simply don’t make the edges so sharp, they feel unnatural.

To blur the edges, you can try the following:
-copy the plate layer
-put it on top of the cg element
-group it with the cg element
-create the selection from the alpha channel of the cg element
-contract it as much as you think is needed
-create a mask from this selection, and blur it a bit
-blur the layer as you need

#11

When CG “shares the world” with real life, above all else you need to look at the other objects; the real ones. Your reference image is mildly overexposed with a definite bluish cast. The real tires on the real cars are flooded with light, and grayish. It’s utterly impossible, your eye sez, that (for example) the seat on the bike would not be equally reflective. And so on and on and on.

The other element to consider, and the one which most creates (or as the case may be, counters) the “decal effect” of course is the shadows. Shadows, both cast by the object and those cast upon the object by the object itself, must agree precisely in spatial orientation, density, and color.

You literally need to take RGB (and/or HSV) readings from points on the reference image to give quantitative meaning to “what your eyes tell you.”

#12

Thanks for the replies people.
All very helpful stuff.
I’m confident I’ll reach my goal with your help.
I’m trying out different programs as suggested by Mister 3d.
So it’s back to the drawing board.

I do want the bike to look immaculate as if it is either brand new or has had loads of preparation time spent on it like polishing of the paint and chrome.
But I do understand that doing so will make it more prone to stand out from the background (as evolucian mentioned about the chrome being too perfect).
I know the tyres could be loads more realistic (as pointed out by sundial), I’m just using a plain rubber material.
I would like them to have blistering/road dirt e.t.c. on them as if they have maybe a few hundred miles of wear on them.
Does anyone know where I can get the bump map files I need for adding those effects to my tyre rubber material in maxwell?

Here’s an updated image.
Blurred the outside edges of the bike and de-blued it a bit, added a torquoise tint and gradient to the shadow, desaturated the chrome.
Still to change a few more things suggested by others.

#13

you still need to fix those blacks :slight_smile: sample the colour of black under that car in the bg, your blacks should never be blacker than that (and more blue).

overall picture (the bike part that is) is too saturated and too grainy.

the shadows need to fall on the … (whatever the english name is for the sticks that balance your bike)

your reflections are blooming too much, take the bike in the bg as a refference and you’ll see that they’re softer.

i would also put a bit more “life” (degredation, dirt) in the tires, they look too new.

also, does your rendering have occlusion? if so, crank it up on the metalworks so the creases are more realistic

#14

I’ve decided to redo it from scratch as I noticed the focal length was out by too much.
I’ve rendered all the channels seperately in maxwell (all the channels that maxwell does).
So I’ve got reflection, diffuse, shadow, fresnel, zbuffer, roughness and alpha.
Can somebody tell me the proper order to layer these channels in photoshop and the blend option for each one?
I tried fusion and nuke briefly, but I don’t think it’s going to be worth me spending weeks or months learning a new program for a purpose that I probably won’t use very often.
If I take too long doing this second attempt I’ll just upload all the seperate channels and hope that someone else does it for me.
I’ve already spent ages on the first attempt and it’s still pish.

Cheers

#15

It seems to me that the main issue (as has already been mentioned) is that the motorcycle is too sharp. The photo that you are compositing into is kinda blurry(due to a point and shoot camera, and jpeg compression, I’m guessing?), yet the motorcycle is very sharp. I noticed that you added some noise to help with that, however in my opinion you have a little bit too much noise now. I think that reducing the noise on the motorcycle and adding a little more blur to it would help alot. Blur before adding the noise though. Mister3D’s method for adding that blur sounds like a great one. Unfortunately there is not much you can do if you really want the motorcycle to be crystal clear and still look integrated into that photo–the photo has some issues regarding exposure, colors, and compression. However, I think you could get it to look pretty cool with some color correction and trying to make it look a little more stylized.

Good luck!!

-Pete

#16

Here’s my re-done image.
I don’t think this is much better than my first attempt, or I may even be getting worse.
After you’ve looked at the same image over a 1000 times I think you start to go a bit mental.
I changed the focal length in maxwell to match the focal length of the original background image.
I’ve got a better rubber texture for the tyres, but it’s still pish.
I haven’t got a reply from my post in the textures forum for how to add dirt to the tyres so they still look brand new.
I know the blacks are too black compared to the car, but they’re not too black compared to the other bike.
I don’t think I’ll spend much more time on this as it’s doing my head in, I’ll maybe make a few more changes if I get more suggestions.
I think learning to be good at compositing is going to be a long term thing, there’s much more to it than I first thought.

P.S. I noticed in firefox that I can’t display the full image in this page and also can’t scroll left or right.
Depending on your viewing resolution, it may be better for you to download the image and view it fullscreen. It’s 1600 x 1200.

#17

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