Back in the day my company had a regionally-slightly-popular Linux distro. Every couple months we'd burn 500-700 discs. We were small enough that it didn't make sense to mass produce, so we burned them ourselves.

We would occasionally get reports from people of being unable to read the discs, and so we went through ~6 months of investigation, test shipping to relatives, paying our customers to ship the discs back so we could check them.

Eventually I found that while every disc would validate by checksum of the entire disc (part of our burn process), if I tracked the time required to read every block, the discs that people had problems with would tend to have some spikes in the time it took to read some blocks. The drives we were using would read them, sometimes taking an amazingly long time to do so (like 30 minutes instead of 2), but users drives would just fail them.

Eventually I wrote a new validation process that in addition to the checksum used the timing information as well to determin if the disc failed, and at that point our failures in the field basically went to 0.

But, we got really sensitive to vendors of discs. Basically it was Taiyo Yuden or nothing. Some big brands would give us 20% failures to burn, where Taiyo Yuden was <1%.

I do love optical media and have a considerable CD, DVD, minidisc, and blu-ray collection. Like a Luddite, I still enjoy burning my own.

I especially like my Superscope disc copier. It completely disregards copy protection and I frequently make a backup of my favorite CDs which I store. Although much of my stock are older blanks (like those listed in this article)I’ll be sad if CD-R disappears from the market.

Pioneer publish the approved media list for their drives but it's not really detailed enough since it only lists by manufacturer while the firmware is operating on manufacturer plus media code: https://www.mfdigital.com/downloads/Pioneer%20111%20approved...

You can potentially get better results by patching your discs into your drive's firmware using MediaCodeSpeedEdit: https://ala42.cdfreaks.com/MCSE/

Oddly, the photo CDs I got professionally written were great.

I am not sure the authors spectrometer test(which was very cool, avidly reading that series of articles right now) would reveal anything as polycarbonate is naturally quite opaque to uv light.

https://en.wikipedia.org/wiki/Polycarbonate#/media/File:Visi... Note how the transmission is dramatically reduced once past violet.

Fun fact ordinary clear polycarbonate eyeglasses do just as good a job as sun glasses at protecting your eyes from uv.