The yellow-lid, blue-lid or red-lid can all be used in a Varicam. What will be affected is the amount of shoot time available on the tape relative to what time is printed on the cassette shell. A Panasonic AJ-HP64ELG (red lip) will give you 32 minutes rec time in a Varicam. For a blue lid divide by 2 or 4, for a yellow lid divide by 4 or 8. Only use "large" shell tapes, regardless of lid color.
Hope that helps.
- Tom