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Comment by meetups323 | Hacker News Reader

A neat material. I had a decorative mirror that unfortunately shattered, I was able to paint the backing with this and mount the shards atop. Creates a cool contrast, with the mirror reflecting nearly 100% of visible light and the the backing nearly 0%.

I also took some shards of the mirror and coated them with the black, then mounted them throughout the house. It makes it look as if some of my universe's texture shards didn't fully load or the backface culling algorithm is buggy. :)

It an interesting material to look at, the uniformity gives your eye nothing to hold on to, making it hard to focus. I recommend trying it out it for anyone interested, the small bottle is pretty cheap and covers just over a square meter. (I needed a few coats, if you preprocess the surface according to the instructions you'd probably lose less to absorption and get more coverage)

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I would love to see a picture of this

Second this

Yes, photos, please :-)!

A photo could not possibly capture the effect. Turn your monitor off and you will see what a digital photo of this black would look like.

Sure it would. And capturing the contrast between the regular wall and the black would give you much better results that turning your monitor off too.

There are lots of cool photos out there of super black material.

I turned my monitor off and saw the most disgusting creature staring back at me. No idea why you'd want to paint that around your house.

A common mistake. You need to look at your monitor straight on, not at a 45 degree angle where it can pick up a reflection of your child.

If the camera has sufficient dynamic range, then it can give a sense of the effect, even if it's not as cool as the real thing. I thought I remembered reading that small sensors are worse at dynamic range than other cameras though, so a phone picture is least likely to capture it compared to other devices.

The camera can't capture it fully of course, but here's the gist: https://imgur.com/a/zPGrkNp

I've got just enough imagination to convert the black to void so it's a very helpful picture, thanks!

Ah yes... phantasia :)

What a strange image! I fully expected the black painted portions to just be ... completely black, since after all the whole point is that it reflects nearly zero light. But that's seemingly not the case at all.

You can download the image and put a black stripe over the top of it to compare, and the difference is quite striking. My color picker tells me that the black in the center of the mirror has a lightness of about 17 out of 100 (that's L in the LCH cylindrical color space), which is really just a medium gray all things considered.

I wonder if this is due to imperfections in the paint and surface, or if the camera used just has an extremely high black level for some reason.

I imagine its a limitation of the sensor capturing the image. When you use a tiny sensor on a phone its doing lots of post-processing, including bumping saturation and brightness.

The apparent haze in the black portion of these photographs appears to be a product of inexpensive camera optics, likely a smartphone with a bit of finger grease on the lens. If you know what you're looking for, this haze is noticeable across the entire image but especially the left third.

This is a common artefact of cheap lenses (or, for that matter, a lens of any quality that is smudged or dirty) but it goes unnoticed by most people in most circumstances.

Good explanation - that does seem pretty likely. I hadn't really considered the possibility that it was a phone camera.

Yep, "Shot on iPhone 12 Mini" :)

Tried again after giving the lens the a nice rub of my shirt, the luminance seems to be approx 1/10th. https://imgur.com/a/5tbeJZT

Thanks for sharing, this must be a really fun conversation piece

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