Wow! That's a lot of work! Nope, I just got an extension tube set for cheap, and whacked the om lens onto it (it just fit with a little encouragement!). I ended up with a 200mm that wouldn't focus to infinity, but worked ok for Closeup. I didn't do a permanent wedge onto the tube, as I have found out that this lens will fit onto a penax q camera, giving a x5.7 boost to the 200mm focal range! That appeals to me, so I have carefully put away the lens for use when I save up and get a secondhand q and om adapter...
My local camera shop is closing down, and I have picked up a lot of stuff very cheaply. I bought an old Bell&Howell 100-300mm lens for £10 so making the 200mm redundant really. Though, it's a big beastie to carry round all the time
My DIY skills aren't that great, so it's probably best I don't try and convert the om lens. I'm far to impatient and clumsy to get a lens mount ground down to 0.5mm accuracy!!!
My new lens has evidence of a bit of fungus round the edge of the front lens, which I didn't spot in the shop (the front lens needed a proper clean from being at the back of the cupboard). I have taken some test shots, and it doesn't mess with the picture at all. I'm now researching fungus, and I don't think I will be brave enough to try and clean the inside of the lens myself! I guess I will just keep the lens warm and dry, away from my other lenses, and just use it until I can afford a better one.
Thanks for the practical tips on how to convert the om lens, it is tempting to just have a go as the lens only cost me £10 too! I can't believe how cheap the old stuff is. I shoot manual and like to focus manually too, so I just don't have any problems using the old lenses. Maybe it's because I don't take photos of many fast moving objects??
I also picked up an old flash gun for £10 too... Pentax sure is value for money!! One of these days I will be able to afford a new camera(!!)