# Accessing Non-Normalized Depth Buffer

**URL:** <https://forum.aousd.org/t/accessing-non-normalized-depth-buffer/992>\
**Category:** USD\
**Tags:** rendering, beginner\
**Created:** [November 28, 2023, 5:50pm UTC](https://forum.aousd.org/t/accessing-non-normalized-depth-buffer/992 "2023-11-28T17:50:31Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Nick](https://avatars.discourse-cdn.com/v4/letter/n/f9ae1b/32.png) [@Nick](https://forum.aousd.org/u/Nick)\
**Post date:** [November 28, 2023, 5:50pm UTC](https://forum.aousd.org/t/accessing-non-normalized-depth-buffer/992/1 "2023-11-28T17:50:32Z")

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Continuing the discussion from [Seeking Advice on Optimizing Equirectangular Panorama Map Rendering Code](https://forum.aousd.org/t/seeking-advice-on-optimizing-equirectangular-panorama-map-rendering-code/959):

I am using ‘depth’ AOV to derive an occlusion map. The issue I am facing is that the depth appears to be normalized to the min/max depth, rather than related to the near/far clipping planes. I have no way of determining if a value of 255 is unobstructed or the furthest pixel.

I would like to transform the pixel values back to absolute depth.

Thank you in advance for your help!

Best regards,  
Nick

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**Author:** ![Nick](https://avatars.discourse-cdn.com/v4/letter/n/f9ae1b/32.png) [@Nick](https://forum.aousd.org/u/Nick)\
**Post date:** [November 29, 2023, 10:30pm UTC](https://forum.aousd.org/t/accessing-non-normalized-depth-buffer/992/2 "2023-11-29T22:30:50Z")

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I found that using the ‘color’ AOV while setting RenderParams.clearColor with alpha set to 0.0, and using the alpha channel to determine occlusion, met my objectives.

Nick