Files of this type and auxiliary type contain a packed Apple II Hi-Res graphics screen.
Files of type $08 and auxiliary type $4000 contain a packed Apple II Hi-Res graphics screen which has been packed with the same algorithm that PackBytes on the Apple IIGS uses. This algorithm takes the 8K graphics screen and produces a file with an indeterminate length and internal format, so no "mode byte" at offset +121 is supported as it is with other files of type $08.
You can display a file of this type and auxiliary type by loading it, using UnPackBytes to decrypt the data, moving it into a high-resolution display buffer ($2000 or $4000 in the standard Apple II memory map), then simply toggling the appropriate display soft switches.
File type $08 was originally defined as an Apple /// FotoFile, but now it is useful for those applications that wish to save high-resolution or double high-resolution data with a file type other than $06, which is a standard binary file. If you choose to use this type, you should remember that older applications which do not check the auxiliary type may attempt to interpret these files incorrectly.
This and all of the other Apple II Technical Notes have been converted to HTML by Aaron Heiss as a public service to the Apple II community, with permission by Apple Computer, Inc. Any and all trademarks, registered and otherwise, are properties of their owners.