One thing I often ask myself, and see asked, is the repeatability and accuracy of quality scans made on consumer drives. I think it has been concluded that the accuracy and repeatability can be quite limited depending on the disc and sets of drives used.
I recently acquired a Lite-On iHBS312-2 drive and I have owned a Lite-On iHBS 212-2 drive for a while now. Most of the quality scans have been made using the older 212, but I wanted to see how quality scans compare and also have a chance to test PRODIS-CR0 BD-R media which is available on eBay under $1 per disc!
So I burnt an Opti-Drive Control test disc at 4x on the iHBS212 and without removing the disc, did a quality scan at 4x. This eliminates the possibility of additional handling dust and oil problems. Then this was quickly transplanted to the iHBS312 drive, where a quality scan was run at 4x (and a slight increase of errors was to be expected from possible dusting). The results are somewhat interesting.
The reported trends from both drive seem similar with the exception at the inner area where the 312 seems to report much fewer errors. The jitter profiles are similar, with a lower absolute jitter value being reported by the 312. Overall, the 312 reports lower error values … but visually the trends seem similar. The PRODIS-CR0 media itself isn’t spectacular for quality, but it’s not the worst I’ve seen either. Only time will tell how long it will last.
A test the other way reveals interesting behaviour too. A disc was burnt in the 312-2, 4x was selected but 2x burn was achieved as I forgot to change the direct overwrite/streaming options and the drive was doing a self-verify during write. Testing the disc while still in the drive (without removing) yields a very good result, whereas transplanting to the 212 shows increased error rate. The jitter trend is the same but the absolute values differ somewhat. The additional spikes are expected from the potential for dust pickup from transplanting the disc from drive to drive.