Truncated depth problem in depth images

Using a Python rendering script, I rendered albedo, normal, and depth images.

Below are example an albedo and corresponding depth image. I am not getting why depth is truncated at some moment. Could anyone please advise how I can get the depth of the entire object?

For the rendering script, I referred: https://github.com/panmari/stanford-shapenet-renderer.

• What format are you using for the depth images? – user1853 Jul 18 '17 at 0:23
• Yeah, that could potentially be an issue, if you are not using an HDR file format you are technically limited to 256 shades of grey for depth information – Duarte Farrajota Ramos Jul 18 '17 at 0:25
• It saves the depth images as in PNG format now, – YW P Kwon Jul 18 '17 at 1:17