Here is a thought.. Knowing that getting a Rollei flash unit and the ability to use with real bulbs is not realistic. I was thinking what could be done by using a semi modern flash on 3.5F series Rollei or any other Rollei TLR. If so.. What would set you Fstop and shutter speed at? Probably use a stroboframe too.
1. If you want to shoot bulbs you can; it just takes a bit of effort to get the right gear.
2. With a leaf shutter and strobe you can use any shutter speed. The aperture is a function of distance. Learn to use the calculator on the side of the 285. You can either use the auto settings (colors) or manual. The calculator tells you which aperture is appropriate for your film speed and subject distance.
Paramount makes wonderful cords. You need one with Vivitar tip... but you really don't need a Rollei locking tip unless you really want that. A regular PC to Vivitar will work just fine.
OK.. Found it.. It's a little different. It has an icon of small light bulb and lighting bold bolt icon next to it. The same lever is the self timer too.