Ewan_McMahon wrote:Though my boxset copy was supposed to be released in 2005, I do wonder if one of the older 2000 copies somehow got into my box
It is common practice for distributors to repackage their older discs to get rid of their surplus stock. Boxsets are often repackaging of their existing older releases. Sometimes the disc labels are changed, sometimes not (I have some of those).
It is almost a given that the disc you bought in the boxset in 2005 is the same as the old release from 2000.
Ewan_McMahon wrote:DVD-data should all be from one original source, therefore all produced copies should be identical right?
Here goes for a "bad" explanation:
DVDs are produced from a master. There can be multiple transfers of a film from the original negative to digital. Each transfer is a multi-step process of scanning the negative, repairing damage and cleaning-up.
If anything happens during the process, any subsequent masters produced from the same intermediate source will have the same defects.
Access to certain transfers may be restricted to the company which paid for the restoration, which explains quality differences between releases.
A bad transfer can trigger a producer/distributor to get a new transfer done, but it can be costly. The idea of a remaster is going back to the source and doing a new master.
During the process, things like re-framing and color-correction can done using the theatrical print for reference.
Se7en (1995) has a good DVD, where part of this process explained in a featurette, including a list of changes compared to the theatrical version.
Perhaps you want tighter framing (more zoomed in) and/or you want more of the top and less of the bottom (and vice versa). Some have a different aspect ratio due to these changes, either as open matte or cropping the sides.
As for other issues, I remember one release of
The Silence of the Lambs (1991) erroneously had the first bit of the opening titles missing, since the overlay effect wasn't applied.
It is very likely that later anamorphic transfers and Blu-ray releases have other choices made than an early non-anamorphic one. Especially one which would be seen as an error.
Older releases may have artifacts that weren't as visible when they were first released, while newer releases may have too much DNR (Digital Noise Reduction) to smooth out flaws but removes detail.
Ewan_McMahon wrote:I just find it curious how I have not found any evidence anywhere (on Amazon-reviews anyway mainly) of anyone else having mentioned that their boxset copy also has this strange line-glitch thing like mine has. Or come to think of it - a similar effect on ANY other DVD title!
The Amazon reviews don't seem to mention anything but the movie itself. Nothing about picture quality or anything, so they are nothing to go by. Given the release is an older one with a non-anamorphic transfer, it is likely considered subpar already.
On a CRT TV screen it will probably look fine because of the overscan, so anyone not seeing it on a widescreen will not notice, but I could be wrong and the weird lines are too far in. Maybe it is more noticeable on a computer, I don't know.
Do remember, this is just me theorizing, not fact. I could have said, that this is a disc manufacturing error or your player, and be equally wrong. I tried to apply some logic for an explanation other than manufacturing error, but without proof from another copy or frame-by-frame comparison with a different version, there is no way to know for sure.
As for different examples, I can't come up with a specific example, but I do remember a non-specific bunch of movie releases where a VHS version has a wider angle in shots than the higher quality DVD ones, so maybe having tighter framing is the more common choice.