[flancian]

  I had downloaded the final Aldus TIFF specifications document, hoping to find the author’s name. However, the name is seemingly written in white text on white paper - making it invisible. What?

Is there an explanation for this that I missed? Was it an Easter Egg left by the author?

[mananaysiempre]

Just as a side note, there are two versions of tiff6.pdf (titled “TIFF, Revision 6.0, Final — June 3, 1992”) on the ’net: one[1] that mentions Aldus on the title page and one[2] that mentions Adobe. Only the Aldus one has the invisitext. (Curiously, the metadata says it’s newer.)

[1] SHA256: dbcdf729182937ecff415dfd06806894bf03bfd741291aa3ad7ba45335673def, modify date 2002-05-10, created by Acrobat Distiller 4.05 for Windows, e.g. https://www.itu.int/itudoc/itu-t/com16/tiff-fx/docs/tiff6.pd...

[2] SHA256: 8cb1e1a2226e423ba8b88f57366a30ef1b7ad6109443ebdda072b952739a8d76, modify date 1995-09-14, created by Acrobat Distiller 2.1 for Power Macintosh, e.g. https://download.osgeo.org/libtiff/doc/TIFF6.pdf

[EvanAnderson]

I've found a number of hidden items in PDFs masked in the same way. The one that comes to mind immediately are Dell product code names hiding in official spec PDFs. (The PowerConnect 6200-series switches are "Kinnick", for example.) I always assumed it was a lazy redaction method and people weren't necessarily aware the text wasn't actually redacted.

[tyg13]

Depends on what format you view it in. For the printed version of the spec, it's sufficient ;)