This could probably be posted in the 35 adaptor area but since it's going to be for the A1 I'm putting it here.

I am getting ready to get one of the 35m adaptor solutions - at the moment I'm leaning towards the brevis simply because it's in canada. A flip and follow focus version is close to being available. (but I'm not married to it) I think the letus has two compatible mounts on it, brevis you have to choose.

What I was wondering was, I have a few lens sitting around from my old pentax K1000 days and am completely newbie on if they would be worth using or if they'd even be compatible.

the lens are as follows: (they all mount on the pentax body)
tamron 28mm 1:2.5
vivitar 70-210 45-5.6
smc pentax-A 50mm 1:2 (i've read up on this and is considered run of the mill)

filters:
rotating polarized (blacks) and 2 skylight 1As (hakuba and image)

I'm also unsure which mount you'd need to choose to be compatible with these.

Most people seem to be going for the nikon set if starting from scratch, and the nikon 50mm was a standard for hitchcock (my personal favorite) but I'm almost positive my existing won't be compatible with that. I'm also green on how much budget needs to be set aside to even purchase a new set of lens if my existing aren't worth it.

Any light shedding would be great.

Trish

i can't really speak to the brevis or letus, but redrock has a pentax k mount for their m2 adapter. i would check with the adapter manufacturers to see if they offer pentax k mounts.

in any case, once you have an adapter with the proper mount, all your lenses should work with the unit. as you probably already know, you want the fastest possible lenses for the adapter. anything slower than f2.8 can be difficult to use because of the inherent light loss in the use of a 35mm adapter. you will have to zoom past any vignetting, and that's automatically at least a 2 stop loss in light right in the xha1. then the adapter itself usually eats another stop or so. depending on the camera and adapter, you're looking at a 3-4 stop loss. so when you stick a f4.5 zoom lens in front of the adapter, even at wide open, you are going to need a lot of light to get a properly exposed image. i think your 50mm and 28mm lenses are usable, but i would recommend getting faster lenses when you can swing it. a second hand 50mm f1.4 lens goes for pretty cheap ($50-$100).

starting from scratch, older nikons are a good bet because their glass has a good reputation, they can be had relatively cheap, and they work well with 35mm adapters. canon fd lenses are popular too for the same reasons, but canon fd lenses need some fiddling with to adjust the aperture on the adapter. regardless of your choice in lens, just be careful what you buy second-hand. old lenses can be fraught with problems, ranging from scratches, fungus, oil on the aperture blades, and stuck rings.

hope that helps.

Thanks very much for the info. Sounds like starting out with a nikon configuration might be the way to go if I need faster lenses regardless.

Trish