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[lynn22]

Just finished my engraved teapot. I rendered to see the effect of the bumpmap I use to mimic the engraving which is a plain white background with a black design and I get two for the price of one

The left half of the pattern is engraved the right half is embossed.
Anyone seen this before or has a suggestion/solution ?

Many thanks

[Project Test Chamber]

Looks great, I see what u mean but i didn't notice at first. I think this may just be a case of what lighting set up you've got, try changing the angle of the light and see if it changes the bump mapped area. If not then i'm not entirely sure. Is your bump map just made out of black and white? is it ok if you upload an image of the bumpmap so i can take a look?

[Roy_Raimi]

That looks awsome! I couldent tell at first but its still sweet!

[headwax]

Hello I tried for a while to reproduce your problem and finally came up with this....

It's two light sources which gives different shadows on either side of the urn. Because it changes the shdows and the highlights on the embossing from one side to the other you have the appearence of relife on one side and engraving on the other.

[lynn22]

Headwax I fist thought the same but there are no lights in my render.
I also tried it with a light at the left, then positioned at the right but the result remains the same.

No areas in your picture look embossed to me.

The teapot has the same bumpmap on the other side and a render of that side looks OK.
I guess I'll just have to position the pot in the scene showing the other side

Thanks for trying.

[Francesco]

A thought just passed my mind but I really don't know if this is possible (didn't try that): have you checked whether some faces are flipped inside-out?
Just my two cents.
That's a really nice teapot, I love the emboss drawing, well done Lynn.

[Francesco]

Just went back to the PC and just tried that. Flipping faces' normals does invert the bumpmap, but don't know if this is the very case of your teapot.

[lynn22]

Thank you Francesco, I thought of that and checked and all the faces are as they should be.

As my teapot is an actor in an animation, I guess it's like all actors when they have their photo taken, they have their good and their lesser side to show to the photographer

[Francesco]

Eheheh, I look forward to see it acting!
Let us know if you discover the cause of that incorrect bumpmapping, on my side I'm curious.

[VBSmiles]

I'm guessing as the others that it is just the lighting. Even though you didn't add lights, it still has default lighting set up. Usually they are opposing lights, one high and bright, diagnally in front and the other in back and low.
I would try turning the pot and see what happens. Perhaps making a video will help you see the effect more clearly.

Nice teapot btw. Bet it would look great with ART reflections.

[lynn22]

VBSmiles, I have rendered the pot on all sides and that one quarter area is the most prominent in showing the emboss.
Never mind, I may still find out why .... some time

The pot will have a silver, glossy reflection with the handle reflecting in the body, it does look good, but I had it turned off to better show the bumpmap effect.

[fik]

Hi it looks to me like you have one side of the centre part of the teapot with mirrored uv's.
 So that the bump mapping works the other way. Did you mirror half to get inner part mapped? or maybe mirror uv's on one half in what ever you used to uv map. This would give the effect you have.

[ENSONIQ5]

Hi Lynn22.  The effect does indeed look as if the normals are flipped on that part of the teapot (great model btw!), but as you have already checked this I am a little dumbfounded.  I have seen this before, however, where the normals are flipped, though they don't appear to be when checking for the yellow or blue face in point edit mode.  I can only suggest a couple of things:

1) Try the Fix Normals function in the edit menu with the teapot body selected.
2) Delete the bad side of the teapot and mirror it from the good side, ensuring the normals are correct.
3) Flip the normals of the bad faces (even though you know it is wrong), so long as this does not affect the other properties of the material.

If you like you could post the actual model here (or just the body of it) in Anim8or format and I (and other) could open it and see if we can see what is going on.

[lynn22]

Thank you guys for all your help.

fik : nothing was mirrored, neither the wireframe or the bumpmap image.

ENSONIQ5 : the Fix Normals function is grayed out so I guess there are no normals to fix
I deleted half of the pot and mirrored the other half but that gives a split material render (see below). The pot was originally modelled in one piece.
I flipped the normals in that particular area and that fixed the bumpmap but messed up the material.

Anyway here's a close-up of the teapot in its setting in the scene and the bumpmap effect is less prominent and maybe even invisible for the viewer of the final animation as the reflection effect takes center stage showing the whole room which to me is more than enough compensation for the bumpmap mishap.

[mcheccyb]

fix normals is done in object mode i think