[bjoneskx]

Update in Post #5

I recently bought a Vivitar 90-230mm F4.5 TX mount lens. As far as I can tell the adapter currently installed on it is for the Mamiya SX (its M/SX on the adapter) camera series which I believe is a variant of the M42 screw system. I know the TX K-mount is extremely rare so I was wondering if the M/SX adapter might be workable with the Pentax screw adapter for K-mounts. If not would the Pentax ES/F adapter ring possibly work?

I'm still waiting for the lens to arrive but I can take pictures as needed once it does.

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Last edited by bjoneskx; 07-22-2010 at 08:43 PM.

[Adam]

AFAIK the M/SX was a 42mm mount, so you should be all set just with the Pentax Lens Review Database - Pentax Mount Adapter K (M Screwmount to Bayonet) Lens Reviews

[bjoneskx]

Awesome, thanks!

[Nesster]

I have two of these - they've come for free or 'included with' some other lens - but mine are the T4's. Doesn't really matter for mounting on a K-x, but does make a difference when mounting on an ES-II or Nikon film camera

The thing I've done with my adapters - I use a thick rubber band (e.g. from supermarket bundled broccoli or asparagus) or a hair squngie around the stop-down mechanism on the mount, to make the lens act 'manual'.

Here's three different T4/Tx adapters I have (since then I've accumulated more)


The 'CS' one's the most useful when adapting to K mount as it has that push pin for stop down. The others have a sliding bit that doesn't stay slid.

The other way is to modify the mount to keep the pin in at all times - this should be easy and you can copy the way people modify adaptall-2 mounts.

The 90-230 is a good lens, especially at the wider end, with very nice color and bokeh.

[bjoneskx]

Well the lens came in and the lens itself seems to be in good condition. All the rings work smoothly, the glass is clear if a little dusty(outer surface), and the aperture blades are snappy with no oil.

However I am having some issues with the adapter/adapter ring. The first issue is that the locking ring itself is bent, it appears to have been dropped at some point bending the edge in at one part. (3rd and 4th pictures) I wonder if this can be unbent with pliers or some other tool. This probably leads to the 2nd issue which is that the adapter is lose and wobbling when the locking ring is engaged as far as it will go. The ring itself is making contact with a small screw pin on the back rim of the lens.(2nd picture) I assume that is to keep the adapter from spinning. If I remove the pin I can screw the ring down far enough to lock the adapter in place so I may leave it off.

Pic1
Pic2
Pic3
Pic4

PS. If anyone could tell me how to display the imgs from Flickr in a post I'd love you forever.

[Nesster]

re posting from flickr: go here OILU - Openforum Image Link Utility after copying whats in the flickr "copy and paste this HTML into your webpage" box when you display all sizes (copy the size you prefer). Then copy and paste the output of oilu here.

Re the TX adapter - yes you should be able to bend it back using some care... in general, the TX adapters are a bit fiddly to put on, sometimes I struggle for several minutes trying to get it to seat just so. And that's with me having the original instructions and all... The adapter itself that you have looks strange to me - it should look like the P/ES one above.

Here's a pic of the other side of the adapter

[bjoneskx]

Thanks for the Flickr tip. The adapter itself does look similar to the ES one but without the slider on the the side and appears to be in ok condition. The part that is bent is the locking ring that holds the adapters on the lens. I've thus far been unsuccessful in bending it back so I'll probably just try to pick up another cheap/broken TX lens and use the locking ring from it.

[SpottyMatic]

Just a quick question if I may - is the P/ES the best bet for M42 mount for Vivitar TX or are there other M42 options in TX mount...?

TIA