I have recently thought about burning some data to Blu-ray and therefore looked for some cheap blank discs. To my surprise, higher density Blu-rays seem to be much more expensive than lower density ones. In my country (Germany) for example, I could buy a 25 GB BD for 0,44€. A 100 GB BD would cost me 8,77€! At that price, it would be more efficient to store 100 GB on four 25 GB discs instead of one 100 GB disc (1,76€ vs. 8,77€). Sure, if it is one file I would have to split it first and combine it again when I want to access the data, but that effort seems to be worth it.
Why are high capacity Blu-rays so much more expensive, especially compared to HDDs or SSDs where the price per GB/TB usually drops with higher capacity?
Suggesting SSD/flash for archive “cold” storage is uh, not good. SSD/flash drives are temperature sensitive, and have a lifespan of no longer than 2 years if they are not turned on periodically. For someone looking into optical storage, I’d bet a healthy wager they are looking to put some of the most important data in a closet somewhere in case of their traditional HDD setup(s) failing catastrophically. It’s not a bad idea. HDDs are also fine for “cold” storage as well, but they’re still mechanical, and having something mechanical sit there for years and turned on after a long period of time sometimes doesn’t work out well.