Resurrecting an old thread
Hi,
I've finally got my mate with a lathe to knock me up an adaptor to go between my Kowa 663 and Sony DSC-W12. Thought I'd post some info here if anyone else wants to have a go at something similar.
Firstly, I wanted an adaptor that screwed onto the threaded boss on the body at the base of the eyepiece. If anyone else wants to make something like this, the thread is a metric threadform with ouside diameter of 41mm and a pitch of 0.75mm. This is the same thread on the following Kowa models fitted with bayonet eyepieces: TS-601, TSN1-4 series, TSN-600 series, TSN-610 series, TSN-660 series. It may be true for others but I don't know for certain. Using this thread, like the official Kowa DA-1 adaptor, puts the strain on the body, not the eyepiece, which I was concerned about. Being a bayonet fit, I was worried about the eyepiece becoming detached as the load of the camera may cause it to twist off if it was directly attached.
The thread on the camera body was rather more complicated because I couldn't get a thread gauge in there to measure it. I wasn't prepared to pay £30 for the genuine Sony adaptor but found a seller on e-bay flogging "pattern" items for £16 including postage from Florida. On delivery I could see that it was a pattern item for an Olympus C5000, it still fitted the Sony W1/12 body the same, so the camera threads are the same (36mm x 0.75mm pitch?) for both these models. It may have been possible to source something more locally for less if I'd known this.
The camera filter adaptor was turned down to remove the "filter end" thread as this wasn't needed and the remaining tube was press-fitted into the camera side custom made tube (see photo 1). This is a simple tube with a counter-bore to accept the eyepiece. The depth of the bore is such that the rubber eyecup on the 30x wide-angle eyepiece I use can remain in place and the camera lens is free to zoom into the eyecup as needed (see photo 2).
The scope side of the adaptor is a similar counter-bored tube with the 41x0.75 thread in its end. The length of threaded portion is 4mm to avoid standing proud of the threaded boss and fouling the eyepiece (see photo 3). An additional simple spacer sleeve was made to fit over this so that the overall assembly length could be modified as required once assembled (see photo 3). This allows adjustments to be made if the eyepiece is changed for a different length item later on and also allows adjustments to be made by modifying/remaking a simple part rather than having to remake the oddball 41x0.75 threaded item should it be found the measurements were wrong at the final assembly. As it turned out (bad pun) this design adjustment wasn't necessary (see photo 4). The spacer sleeve and scope side of the adaptor are locked together by a grub-screw on the inside (not visible in photos).
The two parts drop together and are held in place by the grub screw that can be seen in the pictures (see photo 5). This allows things to be squared up on the camera screen or rotated portrait/landscape as required before nipping up the grub screw. I'll probably put a knurled thumbscrew in later (B&Q here we come).
The overall length of assembly was made so that the end of the camera lens was only just (<1mm) clear of the eyepiece lens when the lens was at maximum extension, this is when the lens is at max wide angle with the Sony DSC W1/12/5/15. The lens moves in and out about 4mm as the zoom is moved from 1.0x to 3.0x I am pleased to say that I get no vignetting at all over the full range of camera zoom when used with the TSE-14W 30x wide eyepiece.
The overall job is simple for any reasonable machinist as long as they have a lathe with metric screw cutting capability. The 41x0.75 thread is the only difficult part of the job and the machinist will probably want to borrow the scope during this part of the job to ensure it all fits.
The adaptor looks a bit rough and ready due to the chuck marks on the outer tube, but hey, it was made out of bits of scrap aluminium and cost me next to nothing. I'll suffer a bit of rough cosmetic for the sake of saving the cash. For comparison, the official Sony VAD-WA is £30, the official Kowa TSN-DA-1 is £70 and the additional adaptor to mount the two together is another £42. Even accounting for the £16 I paid for the camera filter adaptor, that still buys my mate a lot of beers and leaves me well in pocket.
If you haven't got a mate with a lathe, I'm sure a local machine shop will be able to make you something up for a lot less than the £142 you could pay for the "official" Sony/Kowa setup.
Hope this inspires some people to have a go at making something to suit, not just Kowa/Sony users. It is worth it as you can get something that works ideally for your setup, rather than a compromise to suit a range of different combinations.
Regards,
Duncan.