Subtitles Font Size

[hanguolaohu]

Is there a standard font size for subtitles for SD rez 720x480? 1080p HD rez? My current subtitles are Helvetica Neue size 25 in SD, and I'm doing an upconvert to HD. Any info much appreciated!

Thanks,
Alexander

 

[Blaine]

Don't know if this will help but a similar question was asked on LAFCPUG.