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HolyMonkey-
01-13-2012, 05:46 AM
I have this constant problem trying to create nice reflection on tilted screen surfaces

Lighting and all goes really well, but my reflection in these shots. Such as this screen, tends to turn really boring.


I am using standard radioity with sunsky plugin


The image then looks like this -

http://img94.imageshack.us/img94/8457/screen2ig.jpg (http://imageshack.us/photo/my-images/94/screen2ig.jpg/)

Not much to reflect, and it looks as it should I guess?


Alright, let's try adding a spherical map to just the screen plate itself. Then it turns out like this :

http://img39.imageshack.us/img39/4605/screenez.jpg (http://imageshack.us/photo/my-images/39/screenez.jpg/)

No reflection what so ever.



Here are my settings , I dont know why this happens.

http://img841.imageshack.us/img841/9351/settingsc.jpg (http://imageshack.us/photo/my-images/841/settingsc.jpg/)

On the last image, I've added the metal paint to the screen as you can see no reflection so I am guessing the surface angle?

http://img840.imageshack.us/img840/4308/screen3ke.jpg (http://imageshack.us/photo/my-images/840/screen3ke.jpg/)

Any general tips for these type of shots highly appreciated! Right now it's stationed on a plane with a sunsky plugin.

stiff paper
01-13-2012, 02:42 PM
In this thread:
http://forums.newtek.com/showthread.php?t=101465&page=27

...in post #401, I give away a free table with a scene. The table's boring (unless you really feel the need to have a mid-century formica topped table model) but the scene with it might interest you. It's a very simple setup, but I used a couple of "light panel" objects parented to lights to make the reflections look interesting.

It isn't the way of doing this kind of thing, it's just a way, but it might hopefully set you thinking about similar ways of getting the results you're after.

Other than that, going to a magazine stand and looking at the product shots in the ads will help you understand what photographers do to solve the exact same problems, and where they put their "reflectors" and lights.

evolross
01-13-2012, 03:38 PM
Your also not seeing much of a reflection because it's a flat object. Those spheres in your scene are rounded so each pixel on the sphere has a "normal vector" casting out and pointing at a different part of the reflection backdrop, which is why you see a lot of the backdrop in the sphere's reflection. Your flat screen has a single normal vector pointed at one spot on the backdrop. This is why you don't see much.

3DGFXStudios
01-15-2012, 02:14 PM
Try adding a luminous polygon and place it on the right spot using vpr. This way you can get this nice sharp glossy reflection. Like in this adv http://images.apple.com/euro/ipad/accessories/images/dock_20110302.jpg

HolyMonkey-
01-16-2012, 02:48 AM
Thanks! =)

I usually just add the productshot white glanse in photoshop... more accurate, cant seem to get the angle right using a softbox

Although thanks for the eyeopener. =)

prometheus
01-16-2012, 07:28 AM
That node setup should work, I tried a similar setup, only that I do not not exactly the gradient you use.

tested the same lightprobe etc..and I thing It might be the angle of the board/table.

correct this by changing the image seam angle under the reflection map. in the shading environment tab.

This is where It is handy to have either fprime or lightwave 10 and up and the VPR where you instantly can see reflections while tweaking.

Michael

01-16-2012, 11:17 AM
Flat reflected surfaces will only 'work' if you give them something believable to reflect, even if it's just a placard/billboard image of an out-of focus office interiof!

prometheus
01-17-2012, 01:20 AM
Flat reflected surfaces will only 'work' if you give them something believable to reflect, even if it's just a placard/billboard image of an out-of focus office interiof!

As you can see in his node setup, he has an hdr image loaded for reflection, just need to change image seem angle on camera angle or object angle.

Michael

3DGFXStudios
01-17-2012, 02:58 AM
As you can see in his node setup, he has an hdr image loaded for reflection, just need to change image seem angle on camera angle or object angle.

Michael

But that will change the whole lighting setup and you won't have much control. It's better to put a white poly or softbox in the scene.

Check these images for nice hdr reflection lights. Scroll down to the Lightsmith Collection: http://www.hdrlabs.com/sibl/archive.html

prometheus
01-17-2012, 03:00 AM
But that will change the whole lighting setup and you won't have much control. It's better to put a white poly or softbox in the scene.

Check these images for nice hdr reflection lights. Scroll down to the Lightsmith Collection: http://www.hdrlabs.com/sibl/archive.html

Not necessarly, depends on if he only use it on surface base, and not in textured environment.

Michael

3DGFXStudios
01-17-2012, 03:16 AM
Not necessarly, depends on if he only use it on surface base, and not in textured environment.

Michael

True, but I don't like the spherical reflection map because It's really hard to control the placement of it. If you have a animation for example and want to keep the nice reflection in the screen while you move you'll get a headache controlling the spherical map. It would be nice to have it controlled by a Null object. Of course it can speed up rendering a lot ;)

prometheus
01-17-2012, 04:19 AM
True, but I don't like the spherical reflection map because It's really hard to control the placement of it. If you have a animation for example and want to keep the nice reflection in the screen while you move you'll get a headache controlling the spherical map. It would be nice to have it controlled by a Null object. Of course it can speed up rendering a lot ;)


That might be true..
Maybe a way to control that rotation through nodes?

Michael

prometheus
01-17-2012, 04:25 AM
Here´s a flat surface sample, maybe to small to see on our product pages.
Conductor material and reflection by surface spherical map within conductor node.

This is weigh plate stands...english version not ready yet.
http://www.gymleco.se/Produkter/196.php

And here´s a true photo wich is more grit and dirt on it:)
http://www.gymleco.se/Produkter/195.php

Michael

prometheus
01-17-2012, 04:37 AM
only testing..

node setup to change angle of reflection based on null.
Still only heading rotation.

Michael