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Hi,

This is a recurring problem whenever I want to do a front-on view product render.....there always seems to be a large dark shadow spot. It moves away if I move the camera off axis. I've tried various lighting setups (from HDRI to a single emitter) but it doesn't seem to matter.

Is this a bug or something simple that I'm missing?

Thanks as always.

Is the camera really close to the camera target?

Post an image, and this unpleasantness can be dealt with more swiftly....

Hopefully these images show what the issue is. I'm doing a black on black render (probably not the best test to show a dark shadow!).....here are a couple of tests.

This shows how the image should look, however, I want to be front on to lose the perspective...


This shows the issue as soon as I rotate the camera to face on. I'm using a long lens (1200mm) to lessen the perspective so the camera is a long distance from the subject. The face on surfaces turn very dark and I get a kind of "halo" highlight effect around all the recessed buttons. Whole scene is lit with HDRI so there are no objects casting shadows. Could it be that the light is not bouncing from the surface correctly (angle of reflection?).....this makes more sense for the front metal panel, however the top panel is soft touch rubber so this doesn't seem to account for all the light absorption.


Here are the same views pulled out so you get more of an overview...



Finally, here are two renders shown in silver.....note the dark shadow spot on the front-on version. This happens on every project I have ever rendered, with the only fix to tilt the camera off axis....




Thanks!

Have you tried rendering from a front view from Studio instead of a long lens? I have had some strange artifacts show up with super long lens settings.

reminds me of the dark spot we used to get on std mat preview with dark ref 0 and bright ref 90 color, before the force fresnel option.

i also see a strange grey/black border condition on the lcd display on the second image.
reflection of the ground plane?

I would say it has to do with the environment lighting, what do your IBL maps look like? They are in lat/long format? Have you tried setting up the focal length and then moving the IBL maps around to see if the surfaces reflect the light better (using FIRE)? For the bottom images, I don't think it's a matter of refl0/90 brightness because the surface is flat so it should be equally reflective. If you can, please send me a simplified scene of the two you posted which still show this behavior. You can find my email clicking on my user name.

Definitely not the environment lighting. Here are a couple of tests lit with a single overhead emitter with all environment lighting set to "none" (I've also included screen grabs of the setups and fire windows). Exactly the same thing is happening.....all turns to s**t as soon as the camera is pointed directly at the objects.

Front view from Studio has the same results.

this really is a dramatic different, the two images look like they have two different light setups!

Have you tried moving the camera just a tiny bit off axis? Even if you move it 1cm off from perfectly perpendicular to the object faces you might get better results?

The white halos around the buttons in the 'flat' image would, to me, indicate a bug and may be to do with the camera being perfectly flat to the scene. See what happens when you tweak it off by just a tiny bit.

From you camera icon it looks like the camera and camera target are very close, weird things happen in the shading then. I don't know if it's a limitation but try increasing the camera distance to the target and this should go away. Either move the camera back and reframe, or move the target further back from the camera parameters panel.

Bubbaloo wrote:Have you tried rendering from a front view from Studio instead of a long lens? I have had some strange artifacts show up with super long lens settings.

This!
There's definitely something wrong when rendering from a 'View'. Those artifacts almost killed my project.

The renders look correct, its just that your not catching any spec from the front view. Like Mihai said, you need to position the hdri / emitter behind the viewer, and FIRE would be good to get the position spot on.

Looking perpendicular to a perfectly flat + smooth surface you will only see a reflection along exactly that axis.

That brushed black alu is looking nice.

Not getting anywhere with this I'm afraid.

Here's the setup.....single emitter above and behind the viewer, camera focal length 100mm (I've tried all sorts of lens lengths but the results are all bad). Makes no difference where the emitter is placed either. Same results using HDRI too! This is surely a bug, no?



.....and here's the Fire view.


If I tilt the camera off vertical results are ok....

Could you PM me a link to this file? It will remain confidential.

Cloudman, I know humour's not what you need right now (you need a solution) but maybe Maxwell is so realistic the the dark shadow is actually a shadow of the camera (and photographer) itself!!

oz42 wrote:Cloudman, I know humour's not what you need right now (you need a solution) but maybe Maxwell is so realistic the the dark shadow is actually a shadow of the camera (and photographer) itself!!

I seriously thought it was the shadow from the camera for a while !