I still might be getting more Takumars in future, at the very least I mean to replace that 135MM Rikenon with a proper 135MM Takumar and also to get a 200MM prime. But I probably won't get any more T-mounts unless I run across a cheap wide angle maybe. I do still need an M42 one for my SPII but it's not a huge priority right now.
I've got a full Yashica SLR kit and a basics Pentax (M42) SLR kit (except for the wide angle) and while I do like my Vivitar T-mount so far I do have to get a K mount adapter for my other M42's anyway. The Vivitar T-mount came with the M42 mount. I was actually trying to avoid buying another T-mount adapter just for K as well. They do tend to be a bit pricey from what I have seen so far.
I actually tried to get an FD T-mount a while back so I could use it on my black Canon AE-1 kit which still needs a long zoom, but after looking at the hefty price tag I just decided to forget it and just sell the AE-1. In the end I just decided that I don't want to spend any extra money on that one really. It's definitely an "extra" camera at this point. I don't use it much since I'm not really crazy about it. It's a nice looking camera but it's just too hard on my hands compared to my SPII and my FRI. I find it a bit uncomfortable to use really. I have very small hands. Pentax cameras, most of them, they fit me very well size-wise which is one of the reasons I like them so much. For me they are very ergo friendly. So is the FRI. Old Canon's not so much apparently so the AE-1 is rather redundant.
I'd rather sell that and put the $$$ towards more Pentax stuff. I already have another Vivitar 300MM C/Y for my FRI. It's very comparable to that T-mount so the T-mount Vivitar will only end up on the Pentax cameras anyway. I like that lens though. It's a lot nicer than I thought it would be when I bought it.
I thought going from M42 and using the K adapter might be simpler and less expensive since I will already have one for my Takumars anyway. I just wasn't sure it could actually be done, using those 2 adapters. I actually thought it might cause vignetting? If not that makes the most sense in terms of practicality I suppose just going from M42 T-mount to K adapter, skipping the extra T-mount if I can.
I'm actually in the process of selling off a bunch of filters and some other gear, the AE-1, an old SPI, some other stuff on my local CL. I'm not giving up on my film kits, far from it, but I'm pretty set on staying with Pentax and Yashica and I am selling off the stuff I don't need to fund getting a good scanner capable of doing film strips, some lights, and a few other things my film kit still needs. It's always a trade off me buying gear. I only have so much $$$ at any given time so anything I don't really need just isn't something I can usually afford to own. If I am not going to be using a particular thing a lot then it usually has to go to fund something more important, at least until I start making some real money from my photography and can afford to indulge myself a bit more when it comes to collecting gear.
I can't really afford LBA or CBA, smile. Right now having more than two SLR's and one DSLR is kind of a luxury thing. Ditto having multiple adapters just because one step would be easier when two would still work. Or pocket full of filters that I can't just swap between all my cameras etc. I pretty much routinely streamline the gear as much as I can to keep costs down so anytime I can avoid buying another thing I do.
Thanks for the info it's much appreciated.