The Pentacon Six System
Either body cap does the job adequately, but in my opinion there is a clear winner here. It is the Kiev Arsenal cap. Why? The Pentacon body cap just pushes into place and is held there by friction. I have never had one fall off, but it does not seem to me to be that secure. The Arsenal body cap has a lug which must be aligned with the slot at the top of the camera body lens mount socket, and behind that lug there is a sturdy raised strip. It looks like an inverted “T” (with an extremely long horizontal bar) in the above image on the right. So you put it onto the body and then rotate the camera body lens locking ring and it locks the body cap into place, which gives me an impression of much greater security. It is also thicker and stronger than the Pentacon body cap.
Naturally, a camera body cap is also
essential to cover the front of a 2× converter when it
is not being used, and it is also strongly advised
that you use a body cap on the front of the bellows or
of a set of extension tubes for storage, to prevent
the possible entry of dust or fluff.
Another part of the camera body that
may need protecting is the viewfinder opening.
This is of course normally protected by the
waist-level finder, the magnifying head, the plain
prism or the metering prism. However, you may
not have a spare prism for a second body, or may wish
to avoid the weight of carrying two prisms when going
out to take photographs. As far as I have been
able to see over many years, every Pentacon Six was
supplied with a waist-level finder. However, if
you have a body without a waist-level finder, a top
cap may be a good, light-weight
alternative. It may also save a couple of
centimetres of height if storing a second body in a
tight camera bag.
The top cap is a simple plastic plate
that fits onto the four posts round the viewfinder
opening on the top of the camera and slides forward to
be held in place.
If it is necessary to send the camera through the post, a top cap may be preferred to a waist-level finder or prism, unless they need to be sent too. Likewise, we should only send the lens if it, too, is needed. So in the right-hand image I have also put a front body cap on the camera – although I have here used an Arsenal body front cap, rather than the East German original, which cannot be locked in place, as explained above.
Obviously, any lens that is not on a camera body must always be stored with a lens back cap. It always amazes me when a lens comes up for sale without a back cap, as – apart from the standard lens supplied with the camera body – every lens is supplied with a back cap.
Of course, every lens is also supplied with a front cap, although these appear to get lost even more frequently, perhaps just falling off un-noticed while the user is carrying the camera. Fortunately, buying a replacement front cap is easy, as they are readily available in a wide range of standard sizes and styles, including press-on, clip-on and, less commonly, screw-in. We therefore do not need to concern ourselves here with lens front caps.
There is a wide range of Pentacon Six lens back caps, as every manufacturer that supplied a lens with this mount also supplied a back cap, most of them poor, as they easily fall off. However, for many decades there have been four main lens back or rear caps, all of which are illustrated and commented on below.
Which one is the best? Or doesn’t it matter?
Well, again there is a clear winner, but this time the roles are reversed: the Pentacon is the best lens back cap, which of course means that the Exakta 66 cap is equally good.
Why does it matter? The new Arsenal cap is deeper than the old one, but it still slightly presses constantly on the auto aperture pin at the back of the lens, and although one should not be unduly worried about this, it does seem self-evident that it is better, long-term, for a spring (as for a human being!) not to be under constant pressure.
The outer bottom edge of the Arsenal cap (as seen in the bottom of the two pictures here) is also much wider than the corresponding part of the Pentacon and Exakta 66 caps. Not a major difference, perhaps, but I notice it when trying to fit lenses into pouches and the pouches into an outfit case.
I have where possible replaced the back caps on my Arsenal lenses, whether the caps supplied were the old or the new type, with Pentacon lens back caps. Unfortunately, the Pentacon lens back caps are generally hard to find. I therefore tend to put the Arsenal caps on manual lenses (from Pentacon or other manufacturers), as these do not have an aperture pin that could be depressed.
You will also wish to use a lens back
cap on the back of extension tubes or the bellows for
storage, to prevent the possible entry of dust or
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© TRA December 2012,
Latest revision: June 2020