Originally posted by UncleVanya Understood. But do note that the bag I linked is a frame pack not a simple soft bag. Those style backpacks are meant to be used with these weight loads. Adding adequate foam padding is step 1. You could also just build a hard case (complete with cut outs and padding) that fits inside this style bag. I'm still really unclear how carrying the lens vertically is a problem. With your investment I understand the need for caution - too bad no one out there can likely confirm the way Pentax would have recommended carrying it.
I think you may be right. A pack with a frame would work. Lots of thought needed here.
---------- Post added 08-14-18 at 10:17 AM ----------
Originally posted by gofour3 It's right at the end of the lens mount, inside the lens. The 6x7 800/4 is not listed, but it's the same as the 6x7 600/4.
Phil.
You are correct. It is indeed there. You screw it out from the back. So, what you are saying is a 77mm filter screws onto that thread and the filter is in the back ? WOW strange system. But if that's how they do it, well that's how they do it.
So then I can use ND filters after all.
Big learning curve with this lens ahead.
P.S - on this lens that filter thread has never had anything attached to it, so looks like a rear filter was never used on this lens.
P.P.S - found this
http://skrasnov.com/blog/pentax-67/bayonet-mount-filters/
---------- Post added 08-14-18 at 10:47 AM ----------
what are the highest quality ND filters that could be fitted to this lens?
All of a sudden broad daylight hours long exposures have just become possible with this lens. I really thought I would never get an ND on it.
Does the position of the ND in the back have any ill effect on image at all compared to the normal fitting the ND to the front of the lens?