Bluray to HEVC

Hello guys, I have aproximately 250 bluray ISOs in hard disks (or course ripped from my DISC collection). They amount to about 11tb worth of data so my 3 x 4tb hard drives are full. Recently I had some tough luck economically, so I can't afford to keep buying hard disks to store my backups in, and I am thinking of ways to archive this collection without a lot of cost and loss in quality. At first I was thinking of converting to BD25 and burning in BD25 discs, however this stil requires a lot of money for the burner and the blanks, and since I have a powerful machine, I am currently thinking of converting the whole collection to HEVC seeing as it is more efficient, to save space and keep using the same disks. What I want to ask you about, is if you can recommend a program for the task, and also if there is any standard in HEVC already established that I should follow, to make sure the files are playable in tomorows TVs/machines that support H.265... ( I remember, with divx and avc a simple profile change could result in unplayability). Furthermore, as the resulting files wont be stored in media but in hard disks, what is a good suggestion for the decrease in size to achieve about the same quality as the original? (for a example if in a 42gb bluray the movie alone is 33gb, for what size should I opt for in the HEVC encoder to achieve almost the same quality? (I know in every encode there is loss of quality no matter what thats why I say ALMOST the same), maybe a 70% ratio, so 23gb in this example?)

By the time x265 becomes worthwhile over x264 veryslow, it is very, very slow. Expect a day or two of encoding per Blu-ray on slow presets, so start with the largest and work your way down. Since you're big on quality, consider using SMDegrain; it'll run slower but increase the quality/efficiency without being very noticeable.

You should be aware however not really many people are really using HEVC, the reason is it don't yet delivers the quality it's supposed to deliver, here is the most recent poll: There is a video comparison tool built into StaxRip making it really easy for anybody to compare codec and AviSynth settings: It can be downloaded here: There is a somehow outdated comparison thread, unfortunately nobody posted recently an update there:

If you are using Plex to play this stuff, the clients do not support HEVC yet. Instead the server does on-the-fly H.264 transcode, which is absolute garbage quality-wise. If you're just using VLC on a new-ish system then you should be fine playback wise.

Any re-encoding is going to affect playback quality. Maybe you can see the difference on your system, maybe not, but why take the gamble? I do what others have suggested. Rip the main movie with MakeMKV, and save to a single .mkv file including only the audio tracks and subtitles you need. You have all the extras on the original discs, and I haven't found many worth backing up. You'll preserve the original video quality and save a ton of space on your drives. Also, the process takes minutes per title, not hours like re-encoding.

'qg-strength' ?=? 'aq-strength', or did I miss something?

A bit late to the party, but for what it's worth... I'd just weed out material and remux to mkv, using MkvMergeGUI. Mount the ISO, open it in explorer, find the biggest .m2ts file in \BDMV\Stream, drag and drop that to MkvMergeGUI and uncheck any audio streams you don't want. I wouldn't re-encode unless you want to do AviSynth work on the video (e.g. grain removal), and need to store the result. But good Avisynth processing makes video encoders look fast...