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digitalimagery
11-15-2013, 01:40 PM
What's the trick to getting a real nice smooth seamless background like the attached? I've tried a very large curve made from cutting a cylinder into fourths and extending the ends for the floor and wall and then adding smoothing. Tried the same with a pretty serious mesh, moved lights around and I still get nothing as nice as this sample.

Thanks (as always)
DI

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spherical
11-15-2013, 01:53 PM
Let's see the result you are getting.

digitalimagery
11-15-2013, 02:02 PM
Let's see the result you are getting.

Not the clearest example but you can see these definite hard edges where the arrows are. I'll post a sample of the wire frame once a present test completes (shortly).

Thanks
DI

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Ztreem
11-15-2013, 02:18 PM
You can also do a background image that looks like you want and then setup a shadow catcher plane in LW to get the shadows. Otherwise a curved subd plane in the background should work.

digitalimagery
11-15-2013, 02:21 PM
You can also do a background image that looks like you want and then setup a shadow catcher plane in LW to get the shadows. Otherwise a curved subd plane in the background should work.

That's a good idea but I find the ground plane adds a lot to my reflective surfaces which is missing when I go with that approach (unless I can reflect that plane but not have it render).

DI

jeric_synergy
11-15-2013, 02:28 PM
Just try a bigger radius. and more even lighting-- in RL you'd have a bank of floods to even out the effect.

digitalimagery
11-15-2013, 02:33 PM
This is with the default light. I'll try another with a long area light.

sublimationman
11-15-2013, 02:34 PM
Here is how I do it when I want that type of backdrop.

Just make your backdrop object much, much larger than your main subject.

digitalimagery
11-15-2013, 02:39 PM
Here is how I do it when I want that type of backdrop.

Just make your backdrop object much, much larger than your main subject.

I've tried really scaling it up and it just makes the same problem only larger. I like this cylindrical bacdrop affect. This is a version of the previous with a long area light. Definite improvement but still apparent. Maybe making it wider as well as longer will help. That with sublimationman's technique might get it.

DI

sublimationman
11-15-2013, 02:40 PM
Also, don't depend on one light source. Use area lights and or dome lights, on the background object surface I often up the luminosity to make it more white than is natural. It's all about getting the right smooth sloping curve and proper lighting on that curve.

sublimationman
11-15-2013, 02:42 PM
I just make a long segmented box and use the bend tool to curl up just the end, I then subpatch it so it's really smooth.

digitalimagery
11-15-2013, 02:47 PM
What's the process for sub patching? Do I have to do that when I make the original plane or is there a way to do it to just the curved area. Trying to keep the poly count down where ever possible.

Thanks for the help.
DI

Sensei
11-15-2013, 02:58 PM
I've tried really scaling it up and it just makes the same problem only larger. I like this cylindrical bacdrop affect. This is a version of the previous with a long area light. Definite improvement but still apparent. Maybe making it wider as well as longer will help. That with sublimationman's technique might get it.


Definitely too low poly..
Geometry like from 10 years old scene.

Normal vectors are relying on good sub-division of geometry.
Using triangles instead of quads is also bad idea.

digitalimagery
11-15-2013, 03:04 PM
Which geometry are you referring to? "Geometry like from 10 year old scene." Can I increase the subpatches on this model of do I need to start over (not that it's a big deal). Also, if you reference the model screen grab, there's some pretty serious subdivision going on in the curve and I still see faceting. I need more still? I would think smoothing would handle that. No?

Thanks,
DI

JonW
11-15-2013, 03:05 PM
Not the clearest example but you can see these definite hard edges where the arrows are. I'll post a sample of the wire frame once a present test completes (shortly).

Thanks
DI

118202
This looks more like lighting doing something in the scene.

Remove everything else from the scene & render.

If there is still a problem move the lighting, vertically & forward or backwards to see if the problem moves.

Sensei
11-15-2013, 03:06 PM
Yes, I was referring to screen-shots from #9 post. I would divide it at least 5x more, to have nice curved geometry.. Curved geometry is producing nice normal vectors..
See post #8 how dense he had..

JonW
11-15-2013, 03:09 PM
Also get rid of your 1 & 2 point polys.

digitalimagery
11-15-2013, 03:10 PM
I'll try that. Thanks.

DI

Sensei
11-15-2013, 03:13 PM
Don't rely on sub-patches too much. If you will create box 6 polygons, press tab, it won't turn automagically to sphere. It will be screwed semi curved object with bad normal vectors. Nicely curved source object (no low poly!) is needed since beginning. Otherwise no nice curved result you will receive at end..

digitalimagery
11-15-2013, 03:17 PM
Got it. Thanks everyone. Getting toward the end of my work day and need to get some files ready to crunch. Appreciate all the input and will check in from home once I get there.

Hope everyone has a great weekend. Prayers to all the people in the Philippines.

DI

spherical
11-15-2013, 03:22 PM
The trick is to create a shape that is parabolic in both directions. You can't extend from the tangent point of a quarter circle and have the light incidence be a smooth transition from curve to flat. It happens too suddenly. Additionally, I rock the entire assembly from the floor tangent point back, backward by -0.5 and rock the flat back wall back another -0.5 to further smooth the transition from flat to curved.

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JonW
11-15-2013, 03:42 PM
What's the trick to getting a real nice smooth seamless background like the attached? I've tried a very large curve made from cutting a cylinder into fourths and extending the ends for the floor and wall and then adding smoothing. Tried the same with a pretty serious mesh, moved lights around and I still get nothing as nice as this sample.

Thanks (as always)
DI

118200

Looking at the shadows, there is bright large area light behind but up at about 45 degrees quite close as the shadow spread out & dissipate softly.

There is a smaller but never the less still relatively large, area light directly above as the shadows are tighter & the curved metalwork has bright highlights of quite a large radius.

There is another very large area light in front & to the left, but not as bright (see shadow on radiator grill). They have a similar light on the right as you can see the panel covering the engine has some soft lighting.

Also there is a fill light above facing backwards & down probably 45 degrees filling the top of the background as it looks a bit brighter in the centre area.

There is something somewhere in front pointing at the rims & there are highlights on the rim nuts.

spherical
11-15-2013, 05:49 PM
Here's another, using a DP Infinite at 20 included angle (which is what I used alone in the first test) and adding an area light. By adjusting Pitch of each, you can control the falloff on the back wall. In this case, the DP Infinite is at 107.5 Pitch (it was at 90 in the first test) and the area light, placed over the camera, is at 73.7 Pitch.

118211 118212

EDIT: Just happened to think and went to check. These tests were both done with Smoothing off on the cyclorama. Turning it on made no noticeable difference, mostly due to the resolution of the model that makes up the cyc.

JonW
11-15-2013, 06:57 PM
When using smoothing don't leave it on it's default 89 degrees. Turn it down to a percentage just enough to smooth the poly edges. If you have good number of polys in the curve the percentage will only need to be in the region 1 - 5%

JoePoe
11-15-2013, 08:20 PM
Hey DI,

So.... It could be geometry...... and.... it could be lighting. Sorry.
Unfortunately, I am unaware of any way to visually or numerically check the geometry. You just kinda have to know it's okay. On that note, I will agree with the comment that extending a quarter round won't work. (i've been there). So this is what I do (very similar to Sublimationman). Make a flat plane with "enough" geometry ( I really don't think you ned to go overboard) and rotate (he used bend) with a SMOOTH FALLOFF. That's very important. See the attached image. The second image is a render with that background...... not sure I can get it any smoother. I'm not saying you can't get those artifacts from lighting alone (I've been there too), but if you know the geometry is okay you've eliminated half the battle.

spherical
11-15-2013, 09:14 PM
When I went to reproduce this and did the quarter cylinder; extending the floor and back, I got the same artifacting in the render as the OP. Just wanted to know that it was the change from flat to curve not being subtle enough that was the problem. Like I said, smoothing makes no difference if you have good geometry. I just tried it to see if it made any difference at all with the density I had. It was so good that I forgot to turn it on. On an object like this, where a high poly count really isn't all that much of an issue, just go with the geometry and leave the shading tricks off.

spherical
11-15-2013, 09:52 PM
So this is what I do (very similar to Sublimationman). Make a flat plane with "enough" geometry ( I really don't think you ned to go overboard) and rotate (he used bend) with a SMOOTH FALLOFF. That's very important.

I've never been able to get the Bend tool to operate properly. It starts to go where I want and then wigs-out; gyrating all over the place and finally trying to curl the geometry up on itself. With Rotate, I can't get a curl to happen, period.

pinkmouse
11-16-2013, 02:02 AM
I've never been able to get the Bend tool to operate properly. It starts to go where I want and then wigs-out; gyrating all over the place and finally trying to curl the geometry up on itself.

Seconded. I see tutorials with people blithely bending stuff all over the place. I try it, and just get complete rubbish. Still, at least it's consistent, it was just as bad in 4.5... :)

Surrealist.
11-16-2013, 07:25 AM
I have never had such an issue with Bend. If you try to use it in a perspective view it does not work well at all. Using an ortho view is the best way. That and the ctl key are the main methods I use to tame it.

prometheus
11-16-2013, 10:04 AM
for a simple cyce background..I just create a flat plane, and extend the back edge, I select the back edge points, hit "e" for extend an
The rest is just to set up good lightning, perhaps a light only affecting that cyce, and nothing else.
smoothing of for surfaces, and you do not necessary need subpatch for it.

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Michael

prometheus
11-16-2013, 10:11 AM
You could also try px_bezier in belt mode, to create a cyce... and that gives an option to adjust the bezier curve with divisions, smooth handles etc, and also save out curves etc if needed.
set a large radius in the tube tab, and draw the spline in right views.

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Michael

stobbs
11-16-2013, 10:31 AM
Here's a backdrop using just a flat plane and the layout bend effector.
I think the shading issue reported by the OP is more of a geometry issue than lighting.
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JoePoe
11-16-2013, 10:44 AM
yes,

and if the bend is truly smooth you don't need that much geometry at all.
1) new render
2) wires of backdrop. Just smoothing, no subD.

Stobbs, never thought to do it that way. Gonna have to give it a try. Looks good.

stobbs
11-16-2013, 11:33 AM
yes,

and if the bend is truly smooth you don't need that much geometry at all.
1) new render
2) wires of backdrop. Just smoothing, no subD.

Stobbs, never thought to do it that way. Gonna have to give it a try. Looks good.

Talking about the bend tool I'd forgotten about the one in layout. It works really well - I think it could be good for 'basic' motion graphic stuff, along with 'twist' ,'shear' etc.. and in typical LW fashion you cant even find them in the main UI..

jeric_synergy
11-16-2013, 01:08 PM
.......good for 'basic' motion graphic stuff, along with 'twist' ,'shear' etc.. and in typical LW fashion you cant even find them in the main UI..{emphasis added}
The "discoverability" quotient could certainly be higher. BEND is a deformer though, so it'd never show up in the "main UI".

JoePoe
11-16-2013, 01:30 PM
Oooooh, thanks for reminding me. I knew there was something else I wanted to comment on.


I've never been able to get the Bend tool to operate properly. It starts to go where I want and then wigs-out; gyrating all over the place and finally trying to curl the geometry up on itself. With Rotate, I can't get a curl to happen, period.

Yeah, the bend tool can be a little unruly. But in the end (at least for me) I can get it to pop back into alignment with a little fine mouse play. The ctrl key doesn't seem to constrain much (again for me) when it comes to Bend..... it just sorta pops inline automagically with or without it. The part about the bend tool that drives me crazy is that I always pick the wrong window to use it in. For some reason it bends someway contrary to what I assume will happen. The "right" window is usually the last one I pick. So using Bend goes like this....
Bend, DOH, undo, new bend in another window, DOH, undo, final bend :D.

Spherical..... you say that you can't get a curl with rotate??? Very curious. Are you using a falloff? (I'm sure you are.... but I have to ask :).)

Surrealist.
11-16-2013, 02:36 PM
The ctl key in this case is to control the increments of the bend (5 degrees) not to keep it straight. Keeping the bend straight is controlled by grid snapping in your display properties. By default it is set to standard which is why you see it naturally snap back into place. If you set snapping to Fixed and then using something large compared to your object scale it is easy to keep it perfectly straight.

Also don't forget about using Fixed option and the numeric panel, "Apply" and setting the angle/position manually. Between those two you can add more control and predictability.

Additional tips:

With fixed option you can RMB drag the blue bone's base and tip to place it into position interactively.

A typical workflow for me is to use the default automatic and click in the viewport I want the bend to happen down or away from the screen. Undo, keep tool open. Open the numeric panel and then switch to fixed and use the interactive bone. Set the angle manually and hit apply or use the ctl key to get the desired angle.

spherical
11-16-2013, 03:26 PM
A typical workflow for me is to use the default automatic and click in the viewport I want the bend to happen down or away from the screen.

<Cow in Headlights Look> Now, that's intuitive. You set the tool with the RMB in the port axis you want to see from the side and then operate the tool in another port that doesn't show you the full extent of the effect. In all of the years of reading LW manuals, I have never seen this mentioned. Sure doesn't work like other tools do. Magnet, for example works as expected in all ports, Perspective included. Bend, however, has this quirk of having to go to a port that is 90 out from the view where one would think that the most accurate control and feedback would be. Hence, JoePoe's workflow. Well, cool! Now I have another tool in my toolbox. Thanks for clearing this up; 'cuz I've been fighting with it for a long time and had just abandoned it.

jeric_synergy
11-16-2013, 03:50 PM
Bend tools, in GENERAL, have vociferous debates raging around them. LW's is not the cream of the crop.

stobbs
11-16-2013, 04:04 PM
The "discoverability" quotient could certainly be higher. BEND is a deformer though, so it'd never show up in the "main UI".

So are spline control and bones... There seems plenty of redundancy as to what makes it into the main UI. Why hide something potentially useful..

Surrealist.
11-16-2013, 06:26 PM
<Cow in Headlights Look> Now, that's intuitive. You set the tool with the RMB in the port axis you want to see from the side and then operate the tool in another port that doesn't show you the full extent of the effect. In all of the years of reading LW manuals, I have never seen this mentioned. Sure doesn't work like other tools do. Magnet, for example works as expected in all ports, Perspective included. Bend, however, has this quirk of having to go to a port that is 90 out from the view where one would think that the most accurate control and feedback would be. Hence, JoePoe's workflow. Well, cool! Now I have another tool in my toolbox. Thanks for clearing this up; 'cuz I've been fighting with it for a long time and had just abandoned it.

Well actually, if you think of it this way. Bend is a specific operation. It requires input from the user as to which direction it is going to go and this is determined interactively based on mouse drag and view.

If you want to use it in perspective turn off snapping and you'll get a smooth twist and distortion. If you look at it head on, you'll bend in that direction.

And this, if you go though and use most of the Modeler native tools is consistent. They are all (even move and rotate) based on the angle of view and the mouse input. Modified by of course the interaction modes and snapping or ctl key which in the translation tools snaps it along an axis you first move in. Move and Stretch for example. Where as the rotate tool group ctrl gives you increments of rotation

Since the bend tool is basically a rotation you usually also want to bend in increments to an exact angle and ctl key, like rotate, is assigned there.

A better Bend tool would give you a manipulator in 3D. But since there is no such thing. Modeler needs to know where you want to go with it. And these are how all of the tools - in their ancient wonder - still work for 2 decades and based on technology from the stone age. The new modeling tools of course allow you more options but do not take the place of some of the other tools you need to use.

But if you must stick with modeler you will have a better time of it learning how the tools were intended to be used.

spherical
11-16-2013, 08:03 PM
Well actually, if you think of it this way. Bend is a specific operation. It requires input from the user as to which direction it is going to go and this is determined interactively based on mouse drag and view.

Yes. And if I set the tool along the part, to limit the amount of the part that I want to bend, in the Right (ZY) viewport, I expect to be able to click in that viewport, drag up and down and bend the part.

jeric_synergy
11-16-2013, 08:23 PM
The problem is BEND'S versatility: it's NOT limited to just the axes of the vuport. You can bend in all sorts of 'creative' directions, and to accommodate that, I believes, is why the workflow is as it is.

I think it's a bit of a misfeature, given how many users have troubles with it, and I suspect that statistically most bending occurs along vuport axes. Rarely indeed have I ever needed the bend axis to be on some weird angle.

--To look at this, I reacquainted myself with the Bend Tools oddities, and yeah, it's damn hard to use: 'way too finicky for something that should be relatively simple.

spherical
11-16-2013, 09:27 PM
Agreed. The thing is, Up is Up in any viewport that has Y in it. But Bend only works correctly when, for instance, setting its length limit in ZY and then operating it in XY. If you operate it in ZY, it goes nuts. Doesn't make any sense that it does not work in Z and Y in the ZY viewport.

jeric_synergy
11-17-2013, 01:34 AM
I haven't looked at the dox, but just putting a 180 U-bend in a cylinder seems harder than it should be. No doubt I'm doing it wrong, but OTOH it seems like it should be easier.

jeric_synergy
11-17-2013, 02:05 AM
*never mind*

Surrealist.
11-17-2013, 07:55 AM
The problem is BEND'S versatility: it's NOT limited to just the axes of the vuport. You can bend in all sorts of 'creative' directions, and to accommodate that, I believes, is why the workflow is as it is.

I think it's a bit of a misfeature, given how many users have troubles with it, and I suspect that statistically most bending occurs along vuport axes. Rarely indeed have I ever needed the bend axis to be on some weird angle.

--To look at this, I reacquainted myself with the Bend Tools oddities, and yeah, it's damn hard to use: 'way too finicky for something that should be relatively simple.

Well it is simple. As I said, use the snapping function in display options to keep it where you want it. (Along with the other tips I gave) That is how it works.

No body is trying to make any claims that this is the best Bend tool around. But if you understand how they work you can get by just fine. This is true with all of the stone age modeling tools in LightWave. And the truth of the matter is that they are far too simple for most people. It is just not all that complex at all.

There is a system and logic and it works when you understand it, you just have to think less... ah... "modern"

Be a caveman. You can do it.:D

spherical
11-17-2013, 03:28 PM
Re-RingTFM, with the knowledge of the quirks and looking for info based upon that knowledge, I see the example given as to axes, etc. However, the sentence prior to the example: "The trick is to use the Bend tool in the viewport that is perpendicular to the axis of the bend." "Axis of the bend" is not well described. I took it to mean that if you have a part seen from the side, and that is where you set the tool's action limits, and you want to bend the part up, the side viewport IS perpendicular to the axis of the bend. It isn't going to come out of or go into the screen. Hence, that is where I try to operate the tool—where you can see the affect. Seemed obvious, so the example was glossed over. Where it really operates, and perhaps a clearer explanation, is along the axis of the tool. You're looking at the end of it.

jeric_synergy
11-17-2013, 11:59 PM
In #48, spherical points out a problem with STATIC DOCUMENTATION: even if a subject is "addressed", it could be a piss-poor explanation, OR the explanation just might not resonate/'work' with a significant percentage of users. Does LW3DG really want, oh, 15% of readers to not understand a given tool?

With Dynamic Documentation users could supply alternate explanations of a tool in addition to the original explanation, and thus, the documentation could get incrementally better. The dox as supplied would be a launching point for better and better, more and more complete, dox.

stobbs
11-18-2013, 09:12 AM
I think the bend tool would be easier to use if there was a visual guide in the viewports (like you get with move, stretch etc when in linear falloff mode) as to the axis selected and where the min and max bend amounts will occur on the object. I don't think you'd need much in the way on instructions then.

jeric_synergy
11-18-2013, 09:48 AM
A vertex only preview of what's gonna happen would be nice too.

prometheus
11-18-2013, 10:18 AM
I hate the bend tool, I thought they were on the right track for the bend tool as it was in the discarded Core development, it could give you an easy constrained bend properly.

By the way..a tip for the background, you might want to consider turning off recieve shadows for the backdrop, and add an extra ground plane just covering the ground to pick up the shadows there.
for product shots..it is mostly wanted to have completly white backdrop without any shadowing, and only shadows on the floor to showcase it is grounded so to speak, not always the case, depends
on of course.

Michael