Are there any known problems with DVDAfterEdit?

Please check the Release Notes. Minor issues will only be listed for the most recent release, ie. they will not be backdated to older versions.

Looking at DLT drives, what do these terms mean ? LVD, HVD, SE

HVD means High Voltage Differential, for which there are no SCSI cards available on the Mac. LVD means Low Voltage Differential, and your SCSI card is unlikely to support it.

You should try to find an SE drive, which means Single Ended SCSI.

(Differential means that the device measures the difference between the voltages on two lines, rather than one line always being at ground and the other at full voltage.)

What are the differences between different DLT drives ? ( DLT 8000, 7000, 4000 etc. )

There is a tremendous difference in the transfer rates of the various drive models. If you use a DLT III tape on a later model, the speed reverts to that of a DLT2000. The speeds are:

DLT2000 - 1.25 mb/sec.
DLT4000 - 1.5 mb/sec.
DLT7000 - 5 mb/sec.
DLT8000 - 6 mb/sec.

As you can see, there is a great speed improvement in going to at least a DLT7000, and a DLT8000 will write four times faster than a DLT4000. If you want to read tapes supplied by other people, you need a DLT8000 in order to be able to read a tape created on any drive.

What does "Abstraction Layer" mean ?

Abstraction Layer is a term used to describe the techniques used by "wysiwyg" authoring applications like Ulead DVD Workshop, Apple DVD Studio Pro and Adobe Encore. Roughly speaking, this means they use a "one size fits all" template for commands and the layout of assets on the DVD, regardless of how complicated it is. So, there is an abstract "layer" of commands and structure that is generated automatically. The great advantage of this approach is that users don't have to learn the "nitty gritty" of DVD "spec" authoring, but the disadvantage is that the code becomes extremely complex, even on very simple discs - and, slow to operate as a consequence.

DVDAfterEdit offers an option to delete all the commands in a project and start again, resulting in a disc with noticeably faster menu operation in most players. This process has become affectionately known as "nuking the abstraction layer", and for many of our users has become the default way of working. With a little planning, it can produce discs indistinguishable from those authored in Scenarist or the proprietary Sony and Toshiba systems.

There is a detailed examination of the Abstraction Layer commands of a DVD Studio Pro project here.

What is the best way to write DVD-9 test copies?

Follow these steps:

1. Choose your layer-break point from the cells available
2. Create DLTs or DDP image files on DVD-ROM (UDF)
3. Read the DLT's back as an image file. (Making the test disc from the DLTs ensures your customers are seeing the best representation of what will be on the pressed discs.)
4. Using the latest Toast (it must be 6.1 or higher) mount the image file and burn the test disc.

This method will often result in a disc where the layer-break matches the final pressed disc. However, please see John Brisbin's comments:

'This method generally works because of elements of necessity and elements of luck.

First, none of the readily understood disc image formats on Mac OS contain explicit information about the layer break on a DVD, if any.

Therefore, Toast evaluates the disc to determine an appropriate layer break point. If necessary, it will insert a non-seamless cell to make an appropriate layer break. With a DVDAfterEdit image, however, this is never necessary since a dual layer image will always have at least one appropriate break already in place.

When the disc is very nearly full, there will probably be only one legal layer break and Toast will use the same layer break as DVDAfterEdit did, and you will get an exact match with the tape.

The only awkward case occurs when the disc is significantly less than full, allowing more than one legal break, perhaps at one of several VTS boundaries or non-seamless cells. In such a case, Toast may well choose a different break than you did when you were presented with the option in the Mastering dialog.

While it does not represent exactly what is on the tape, it is usually of no consequence since any non-seamless cell is equally good as a practical matter, so long as it meets the other criteria for a layer break.

It should be noted, however, that Toast could do almost anything in its algorithm that results in a legal break, so unless you verify the position either with Toast's information or with a DVD info utility of some kind, the break may not match the tape.

Why can't the replication house read my DDP images files submitted on DVD-R?

Beware of the Toast "Mac & PC" data option. It creates the PC file system in ISO instead of UDF format, and ISO-9660 supports files only up to 2 GB in size. The replication house are trying to read the DDP file using a PC, and "see" the incorrect file size.

Instead, in Toast 6, use DVD-ROM (UDF) and Data format. (Not video, since you are writing a DDP image file.)

Why does my DLT drive report "format failed" right after it starts writing ?

This is an issue with writing to new tapes for the first time. It will be addressed in a future update. In the meantime, there are a few workarounds:

1. In studio "downtime", start formatting a random project to any new DLT tapes, then cancel as soon as it succeeds. Maintain a stock of "pre-formatted" tapes.
2. Try manually setting the drive's compression settings before it "settles down". This sometimes helps.
3. If suggestions 1 and 2 don't work for you, and you are having this kind of problem when writing DVD-9 jobs (where it's really irritating for the second tape to fail), the failsafe method is:
   
   1. Start writing Layer 0.
   2. If it fails, go to Step (iii), otherwise cancel the Format and then go to Step (iii).
   3. Start writing Layer 0 again, on the other tape.
   4. If formatting is successful, let it proceed, otherwise try again, with either tape, and everything should proceed smoothly.

Will DVDAfterEdit do this...?

Please use the "About" section of this site for a summary of the software's features. You can also check the Feature Requests forum thread to see features other people have asked for but which are not currently implemented.