An example of the difference a service can make to the shutter speeds of a camera - in this case, an RTS II.
Shutter speeds before service:
And, although not the sole reason for the slow shutter speeds, this is the dirt, on the end of a slip of paper, removed from the shutter magnet which can cause the magnet to be slow in releasing the second curtain and cause the shutter speeds to be slow and, often, more erratic.
The 159 focus screen is not considered user replaceable despite it being fairly easy to remove. The problem is refitting it. In the user manual it says the screen should only be replaced at a service centre and with good reason. If not done correctly the screen will, almost certainly, be damaged. I know, I've done it.
I experimented with an old screen to see if I could find a way the screen could be changed without damaging it. Described here is my method found through that experimentation, it's not a manufacturer recommended way.
Before proceeding a method of holding the screen without damaging it is necessary. Later camera models had screens with a tab to be used to hold the screen by but the 159 screen doesn't have a tab. I use a pair of flat tipped tweezers that have had the tips covered in heat shrink cable insulation. This is permanent and I only use them for this purpose but a temporary solution could be some rubber sleeving fitted over the end of some tweezers.
I also recommend the mirror buffer foam be removed. This makes it easy to see the release catch.
First, the camera needs to held inverted.
A piece of card needs to be cut and bent to fit into the camera such that the edge sits against the back of the focus screen frame (see arrow in next picture). The card will stop the frame jumping out of its retaining slot and will also protect the mirror from possible scratching.
Release the screen by pulling back on the catch. The screen frame will pop up. Lift it up and remove the screen from underneath. This is best done by using something with a point to press against the edge of the screen and lift it up then use the covered tweezers to grab the screen and remove it while holding the frame clear. Don't try and remove the frame first, you will probably scratch the screen while trying to remove the frame.
If you do remove the frame after removing the screen, note it has two tabs on it, a wide one on one side and a narrow one on the other, The wide ones goes to the back, the narrow one to the front.
Refitting is the reverse order to the above. Fit the frame first, hold it clear and fit the screen under it. Note the dull (matte) side of the screen goes towards the prism.
Finally, lower the frame but DO NOT try and press down on it to engage it with the latch.
Use a pair of tweezers to pull the latch back as far as it will go. Use the tweezers against the mirror box frame and make sure the latch is held firmly before going further.
This is the most important part of the process. If the latch isn't held back the frame, which is quite flimsy, will get pushed inwards and will scratch the surface of the screen.
With the latch held back, hold the frame into position then release the latch.
This is not an easy procedure to carry out and requires practice of using two pairs of tweezers and a steady hand.
Following on from my previous post of the same title. The KF-M1 lingered in pieces for a couple of months until I finally decided to convert it to a Contax/Yashica lens mount. I've converted Phenix made, Yashica based, cameras before but from Pentax K mount to C/Y. That was fairly straight forward and I expected this to be the same - I was wrong. Converting from a Nikon mount to a C/Y mount turned out to be more difficult. The main issues were due to the way the Nikon mount transfers aperture information to the body which meant the metering circuit was different and also due to the shorter flange to film distance and the wider lens mount causing some mechanical differences.
Without going into all the details, essentially, I replaced the KF-M1 mirror box and viewfinder along with the meter circuit with the same from a Yashica FX-3. The increased range of shutter speeds is a slight issue and, as it now stands, the meter doesn't work if the 1/4000 shutter speed is selected. That's not really an issue. I also added a grip, replaced the shutter speed knob as the original was difficult to grip, and fitted new covers. As I replaced the viewfinder and metering system with the same from a Yashica FX-3 Super 2000, I also gained a flash ready signal in the viewfinder though that required the hot shoe to be replaced with one with the extra flash contact.
The shutter speeds were adjusted and the 1/4000 is just within specification but it's clear this shutter is struggling to reach the 1/4000 speed. Some further adjustment might improve it but I decided to leave it as it is.
The same shutter, used in the Yashica Super 2000, but without the 1/4000 speed, exhibits almost identical characteristics and is already struggling to reach 1/2000. This isn't a match for the shutter used in the Contax S2 though, even that, can struggle to reach 1/4000.
Overall, I'm happy with the result. The camera handles well and with the increased weight of the metal top and bottom plates it feels more solid than a Yashica FX-3. Despite the fact I probably won't give it much use, I think it's a keeper.
The Kyocera F-3 eyecup was used on the Contax S2, 167, Aria and maybe other bodies. It also fits earlier bodies like the 139, 137 and 159 and also Yashica bodies like the FX-3, FX-D, FX-103 etc. I, personally, prefer it to the round eyecups that were used on the earlier Contax and Yashicas.
However, the Kyocera F-3 eyecup has become scarce and when they do become available they are expensive. So I looked for an alternative and found the Canon EOS EF eyecup fits perfectly. It's the same style as the Kyocera F-3 though slightly different in shape. Original Canon eyecups are available and are not expensive but there are Chinese made copies that are available very cheaply on ebay.
The Canon EF eyecup fits Canon EOS 350D, 400D, 450D, 500D, 550D, 600D, 1000D etc. bodies. There are other similar models so, if buying, check it's the correct one.
Here's a few pics of one I bought fitted to a FX-3, a 139 and the KF-M1 mentioned in my previous post.
