Quote Originally Posted by rusty_tripod
Does anyone know the guide number vor Vivitar 365 Zoom Thyristor? Not listed on Vivitar web site.
Thanks

Rusty Tripod
Rusty Tripod:
My copy of "Advanced Lighting Techniques with Vivitar Electronic Flash Systems", Vivitar Corp. 1978, gives the guide # as 80 at ASA 25 (160 at ASA 100). Normal 50mm lens.

Wide/ GN 70 (140 @ ASA 100), 35mm lens.
Tele/ GN 100 (200 @ ASA 100), 105mm + lens.
Super Wide/ GN 35 (70 @ ASA 100), 21mm lens with adapter supplied

This should help somewhat, Howard Tanger