Suggestion to improve wording and structure of NOTE 1 in 10.6.5.1 General

[AmyLin2013]

1.Use of “can contain” instead of “may contain”.
In the context of ISO-style wording, “may” is typically used to express permission or an optional possibility, while “can” is more about capability.
Here, the sentence:
The PDF dictionaries can contain a Type entry with the value Halftone …
is describing what is allowed in the PDF dictionaries, so “may contain” is more appropriate and consistent with the normative style used elsewhere in the specification.

2.“with the following exceptions:” is followed by prose instead of a clear list.
After: … with the following exceptions:
there are actually two distinct exceptions:

• the optional Type entry with value Halftone
• the representation of spot/transfer functions and threshold arrays
  However, they are written as continuous prose without any bullets or clear separation. This makes the “exceptions” harder to scan and less readable, especially for implementers who are comparing with the PostScript halftone dictionaries.

3.Two different exceptions are compressed into one long line.
In:
Spot functions and transfer functions are represented by function objects instead of PostScript language procedures. Threshold arrays are specified as streams instead of files.
two separate constraints are placed in a single run-on sentence. For clarity and consistency with the “following exceptions” lead-in, it would be preferable to split them into separate bullet points.

Proposed revised NOTE 1:

NOTE 1 The dictionaries representing these halftone types contain the same entries as the corresponding PostScript language halftone dictionaries (as described in clause 7.4 of the PostScript Language Reference, Third Edition), with the following exceptions:

• The PDF dictionaries may contain a Type entry with the value Halftone, identifying the type of PDF object that the dictionary describes.
• Spot functions and transfer functions are represented by function objects instead of PostScript language procedures.
• Threshold arrays are specified as streams instead of files.

[AmyLin2013]

The following paragraph "In Type 5 halftone dictionaries, the keys for colourants shall be name objects; they cannot be strings as is allowed in PostScript." sees also a part of Note1？ 你PDF1.7 it's a part of note, could you help to double check?

[petervwyatt]

Tagging @DietrichSeggern