Oil on shutter and aperture blades acts like glue causing them to stick together. In some cases the pivot pins benefit from a fine trace of lubricant and dry lubricant works best.

bartbob wrote:

What type of graphite?

Very, very fine graphite, like for lubricating locks.

I cannot answer you question about other lubricants. But listen to 45PSS, both he and Bert are two of the "go to people" when you have a question.

Steve

http://www.agscompany.com/lubricants/homehardware/183
has the consistent of talcum powder. It's what I use as it is what is available locally. A google search for " extra fine powdered graphite " shows some ultra fine and micro fine powdered graphite.
http://www.graphitestore.com/items_list.asp/action/prod/prd_id/34/cat_id/28
Tube-o-Lube extra fine powdered graphite is 44 microns, micro fine is 325 mesh.

If I had a piece of equipment that the warranty would be voided if I used a type of lubricant on it then I would not use that lubricant until the warranty had ended.