No. ID looks at the font name and the format, so the T1 fonts will remain missing.
OK. But I notice that the list of missing fonts does not specify either PostScript or OpenType. All it says is that I am missing (for example): Mercury Text G3 SC
So, as I understand your reply, InDesign will not substitute Mercury Text G3 SC (OpenType) installed on my computer for the Mercury Text G3 SC specified in the document because the original document used PostScript fonts?
Is there a way to force InDesign to use my installed OpenType Mercury Text G3 SC wherever the same font name is specified in the document?
Assuming the substitution is possible, will it look identical? I guess what I am trying to figure out is whether or not the OpenType format of Mercury Text G3 SC will be visually indistinguishable from PostScript Mercury Text G3 SC.
First off the actual font name for the OpenType version will almost certainly be different from the T1 version, depending of course on the vendor.
To substitute, open Find Font (either from the missing font dialog or from the Type menu) and do the substitution. I'd check the box to redefine styles.
There is no guarantee the font metrics will be the same (they often change slightly with version updates, let alone a remake).
FYI, the missing fonts were identified as:
Mercury Text G3
Mercury Text G3 Bold
Mercury Text G3 Italic
Mercury Text G3 SC
Mercury Text G3 SC Bold
Helvetica Neue LT Std 45 Light
Helvetica Neue LT Std 47 Light Condensed
Helvetica Neue LT Std 55 Roman
Helvetica Neue LT Std 67 Medium Condensed
Helvetica Neue LT Std 77 Bold Condensed
All of the identically named fonts seem to be available for purchase, but only in OpenType format.
Again, thanks for your help.
I'm not familiar with the Mercury fonts, but the Helvetica Neue LT Std is an OpenType font, so it should work if it was included in the package (though you legally need to have your own license for it).