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digitalimagery
11-27-2012, 08:54 AM
I'm trying to create a simple reflection that's very popular these days (samples 1&2) on the face of some 3D text. I'm using a flat piece of geometry colored white to reflect (see ImageC) and I've tried:
1. Using a gradient built in the surface editor applied as an alpha to create the fade off
2. UV mapping a white RGB with a horizontal gradient alpha

Nothing is giving me the hard forward edge and a fading off reflection as can be seen in my sample. This should be so simple yet the standard alpha channel principals used in PS and AE don't seem to apply in LW. Can anyone offer some help? Is there an easier way to achieve this effect?

Thanks.
DI

cagey5
11-27-2012, 09:49 AM
Here's my 2 minute attempt for what it's worth.

Gradient of reflected board is driven by distance to object [null]

[Edit] The gradient is driving luminosity

digitalimagery
11-27-2012, 10:00 AM
Any chance of a screen grab of the setup? I'm too new to LW to understand what you mean by that short description. That's exactly what I'm trying to do though. Thanks.
DI

cagey5
11-27-2012, 10:15 AM
Hope this helps..

digitalimagery
11-27-2012, 10:20 AM
Thanks so much. I think it will. I'll post some results.

DI

cagey5
11-27-2012, 10:26 AM
As additional info the board is also flagged as 'unseen by camera' in the properties panel.

digitalimagery
11-27-2012, 10:57 AM
As additional info the board is also flagged as 'unseen by camera' in the properties panel.

Yup, had that (thanks). I'm set up pretty close to what you sent and I'm seeing an improvement. Thought I had it until I moved the layer (reflective plane). I reduced the width with the stretch tool to better see the full width in the reflection and you can see on the face of the "N" the reflection still isn't fading off completely (image D). I messed around with the alpha sliders and values and managed to get it squared away (Image E). I also played around with the position of the null and can see the affect it has.

I don't really understand how this works - the logic behind this. I never would have figured this out so thanks for the help.

Appreciate your patience.
DI

- - - Updated - - -

BTW. I notice you have more of a hot spot on your reflection. Is this from the light position/intensity?

Thanks
DI

cagey5
11-27-2012, 11:15 AM
The hot spot is due only to the luminosity gradient. Adding more points or moving the null closer will both improve that. This last image is adding another gradient point to intensify the effect further. I haven't altered the alpha keys at all.

digitalimagery
11-27-2012, 11:50 AM
How is it that I'm using basically the same set up you are and my gradient is going horizontal and yours is vertical and what determines that? If I'm being a pain you can tell me - I can take it. Appreciate the help. :o)

DI

cagey5
11-27-2012, 11:59 AM
It can only be a combination of camera angle, board angle and position but mainly null position as that is what will determine the start point of the gradient. Think of the null as a spotlight that will only effect the reflected board, with the light falling off with distance. Does that help to visualize the effect?

digitalimagery
11-27-2012, 12:10 PM
Starting to make sense. Thank you. I'll leave you alone now.

DI

digitalimagery
11-27-2012, 12:57 PM
If I may. In an effort to understand how this all works I reduced the size of the reflection panel (using stretch) so the entire panel can be seen on the face of the text. I'm trying to see which way the gradient falls. In the attached image there is no indication the gradient is being applied. Looking at what is visible in this screen grab, can you tell me what I'm doing wrong? I really hate to take advantage of you but I'm trying to grasp this and it makes no sense to me. Thanks.

DI

JoePoe
11-27-2012, 01:14 PM
I'll jump in for a sec. (and try not to confuse the situation :))

I think your problem is your start/end values for the gradient. Your grid is at 2m yet your end value on the gradient is 10m.
judging by the grid size your whole object isn't more than 100mm or so and only about 300mm away from the null. All of that falls within the very white section of your gradient, so you wont see much of an effect. Try squeezing the gradient setup down to a 1m range. :thumbsup:

I did things a little different, but you can see what I mean. My text object in 1m high and so is my gradient.
(fyi.... in my case the null is right at the bottom of the text.... and I used a black card to reflect. Like I said, I did it a little different. But the gradient is on the reflection layer.)

cagey5
11-27-2012, 01:17 PM
It looks to be the scale of your gradient. Looking at your grid size [2m] your lreflective panel is 1 - 1.2 metres long. On your gradient, your first key is approximately 2m from the start point, so you won't see a discernable effect. Close all the keys up.

What I would do is get rid of all the intermediary keys until you have the base effect you are looking for and then add those back in to give the exact look you are after.

In the 'End' box for the gradient, delete 10m and put in 2m, put a key in at that point with a value of '0'. Does that show an effect?

Matt
11-27-2012, 09:50 PM
You know Apple heavily Photoshop their images to add things like crisp reflections etc.

digitalimagery
11-28-2012, 07:12 AM
I'll jump in for a sec. (and try not to confuse the situation :))

I think your problem is your start/end values for the gradient. Your grid is at 2m yet your end value on the gradient is 10m.
judging by the grid size your whole object isn't more than 100mm or so and only about 300mm away from the null. All of that falls within the very white section of your gradient, so you wont see much of an effect. Try squeezing the gradient setup down to a 1m range. :thumbsup:

I did things a little different, but you can see what I mean. My text object in 1m high and so is my gradient.
(fyi.... in my case the null is right at the bottom of the text.... and I used a black card to reflect. Like I said, I did it a little different. But the gradient is on the reflection layer.)

Thanks JoePoe and Cagey5. This is an area I've never understood real well (sizes of objects in relation to environmental or other reflections). Is there a general rule of thumb as to what size I should be building my models in relation to e-maps for logo work? Can you suggest something? My e-maps are usually in the 512x512 to 1024 x 1024 range. Does that determine what size my models should be? Any help in this area would probably really help me in my work. This is the area I struggle with on most logo animations.

Thanks so much for the information.
DI

digitalimagery
11-28-2012, 07:16 AM
I suspected the still images were Photoshopped. I do the same thing for print or still images within animations. Still, I've seen this same reflection style used in animation (which is what I'm doing on this project) so I thought I'd figure out how it's done. The project I'm on doesn't have a specific deadline so it's a great opportunity to learn something and experiment. Thanks for your comment.

DI

digitalimagery
11-28-2012, 08:25 AM
Going a little nuts here.

I've put my settings close to what was suggested and clearly I'm not understanding the logic here. I'm getting a dark area where my reflective panel is. I've tried putting the Blending mode (Texture Editor) to both Normal and Alpha and there's no change. I've rotated the reflecting panel, changed it's scale, moved the null, changed the "Input Parameter" from Distance to Object to X, Y and Z. Additionally I've changed the "Object" to Null and Reflective panel with no change.

I noticed in JoePoes still the surface all this was applied to was the face of the text. I thought this was my mistake (I had been applying my settings to the reflective surface) but the results were exactly the same. I've tried scaling the reflective panel (and adjusted the gradients end dimension to correlate with that) but the results were the same so apparently i'm retarded.

I've uploading my file for analysis in the event someone can look at it and explain where I'm going wrong. Any help would be huge. Thanks to all who have offered assistance. I'm thoroughly impressed how fast you guys (girls?) throw together what I wrestle with for days.

Respectfully
DI

JoePoe
11-28-2012, 09:00 AM
well, I'm on 9.6 so I'm not sure if something didn't come through, but I didn't see a gradient anywhere in your settings.
(all of the texture layers came in as image map > none..... hmmm).

Anyway, I added a new null right below the logo, and a gradient on the face reflection channel.

Notice the scale of the gradient..... end value 250 mm (and I really didn't need all of it).

JoePoe
11-28-2012, 10:00 AM
Ah ha! (boy I was doing things differently).
So you do have a gradient.... on the reflector (lumin).
So what (I think) is happeneing is that on the red (a medium value) you are seeing the reflection of both the high luminosity and the low - which is showing up dark.
Your gradient was still way out of scale (10m) so the whole reflector was basically zero luminosity therefore you were seeing basically a dark reflection.

Option 2:
Took off my gradient on the logo face.
Took off your gradient on luminosity and just gave it an across the board value of 200 (could have gone with less and just raised reflection value of logo..... and so on and so on....)
And put a gradient on the transparency channel of the reflector (using new null at bottom of reflector object). :thumbsup:
So now you would have high luminosity fading to nothing, not high luminosity fading to low luminosity.

digitalimagery
11-28-2012, 11:54 AM
It's looking better. Do I need to parent the reflector to the new null? And can I just use the free floating null I had in the scene (not being used for anything else) rather than adding a new null? Hey I just noticed you're in Boston. That's where I'm from (Marblehead actually). Work for any of the post houses there?

DI

digitalimagery
11-28-2012, 12:19 PM
Ok, I figured out what's going on. First off I did marry the Reflecting panel to the Reflecting null (the blank null already in the scene). Part of the problem was I wanted an angled highlight to go across the text and since the gradient seems to me based on a global x.y.z axis, rotating the geometry was making the gradient fall off the geometry at an angle thereby giving me a hard edge on the fade out side. Returning the reflecting panel to vertical, parenting everything to a master null (camera/lights included) allowed me to rotate the scene and get the effect I'm after. Still not convinced this is the only (or best way) to do it (probably not) but at least I have a grip on what's going on and how it can be achieved. I still favor the samples you (JoePoe and Cagey5) initially supplied in your uploads, at least I'm in the right direction and and grateful for your help.

Thanks so much everyone. This forum is a lifesaver.
DI

JoePoe
11-28-2012, 12:49 PM
Ha, funny Marblehead!! "Earth" just got a little smaller :). Re: production house.... nope, I'm an army of one.

Glad it's coming together.
While it seems you've got a handle, I'll answer anyway. Yes if you are using the null position as an input value for the gradient it's wise to parent at least those two together.
But you don't have to use the linear X Y Z co'ords. First of all just "distance to object" will drive the effect in all directions (spherical influence).
But a more simple solution (among the dozens available) would be to give the reflector a gradated weight map. And set the gradient input to use the map. That way you can rotate and move the crap of it and it wont matter. That's just one alternative. As you mentioned.... many ways to skin this cat.

Cagey5 - sorry if I've stepped on toes. Didn't set out to highjack thread. Apologies.