Forum: Vue


Subject: Z depth problem (again :)

vincebagna opened this issue on Feb 10, 2008 ยท 11 posts


vincebagna posted Sun, 10 February 2008 at 8:48 AM

Here is my render and it's z-depth. As in my scene there is only the character and the ground (which is what is seen on the bg because of the camera angle), doesn't the z-depth have to be much more detailled?

I mean in the greyscale, we should see the nose darker etc...

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Rutra posted Sun, 10 February 2008 at 10:07 AM

It's probably not sufficiently close to the camera to distinguish the facial features. I suggest that you make the camera much closer. Alternatively, you can boost the contrast in photoshop.


vincebagna posted Sun, 10 February 2008 at 10:19 AM

I already tried to high the contrast in Photoshop, but all i get is a sort of layered pic, that will not make a good mask :(

About the camera, i'm never sure of which settngs to apply. For this scene, i have a 200m focal distance camera. I don't know what is fine for portraits (if there is a general rule). I always work on the trial and error way, and when i get something that please me, i go for it ^^
But if there is a better way, i'm open :)

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vincebagna posted Sun, 10 February 2008 at 10:20 AM

Btw, we can see in the pic above that the transmap of the hair is not really good taken into account in the z depth...

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Rutra posted Sun, 10 February 2008 at 10:36 AM

This is taken with the camera at 50mm (more or less normal for real world cameras). There are many grey levels and the facial features are distinguishible (nose being darker).

Rutra posted Sun, 10 February 2008 at 10:38 AM

With a little level tweaking in PS...

Rutra posted Sun, 10 February 2008 at 10:42 AM

With even greater level tweaking, the levels become smoother and more contrasting.

vincebagna posted Sun, 10 February 2008 at 11:01 AM

Wow. You made it clear here ^^
i tried with a 50 camera and indeed get a z depth with much more level, but i'm not able to smooth it like you in PS :(

You played with level, what is the overal shape of the curve?

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Rutra posted Sun, 10 February 2008 at 11:47 AM

First, I saved from Vue directly in PSD format, 16 bits. Then, in PS, I edited levels (not curve). Here's the "before" (I will post the "after" in a second).

Rutra posted Sun, 10 February 2008 at 11:47 AM

Now the "after".

vincebagna posted Sun, 10 February 2008 at 1:32 PM

Thanks Rutra ^^

I made a confusion between curves and levels (due to my 'interpretation' of the french translation). Now i get it and it indeed changes a lot LOL

I only played with the contrast before, now with levels i can make it clear enough to be more useful, many thanks ^^

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