goal, is to get
an old, screw mount lens - any brand, so long as it has the
(commonly known as the Pentax/Practika thread), on to a modern (film or
digital) "K" mount camera.
Here we show the Super-Takumar 50/f1.4 lens (introduced in 1965)
mounted on a modern, Pentax 10d Digital camera.
focus is maintained, and the system works perfectly.
of course, only manual and auto-exposure is only possible in the "A"
(Aperture Priority) mode, and with stop-down metering.
this, I chose the Roxsen adapter, available
on eBay. I have found Roxsen adapters to be
consistently well made ... something I cannot say about other
brands I have tried.
This Roxsen adapter is no exception ... in fact it's design and
manufacture is a step above even Roxsen's usual standards.
problem lies with the removal tool or "key".
The Key (on the left) is apparently made for several
and it works poorly with this particular adapter. Let me show
First, mount the adapter on the lens and then mount
the lens on the camera.
care when you mount the lens, so that the spring clip (latch) is
compressed when you line up the red dot on the adapter to the red dot
on the lens mount. This can be accomplished by canting the lens a wee
bit, as you insert the lens in the bayonet mount.
The insert photo shows the spring clip (latch) in more
will find it fits perfectly and infinity
You remove the lens, by unscrewing it. You
will find the adapter
remains behind, so you can mount several M42 threaded lenses, one after
the other. When you are done, remove the last lens by
where it gets tricky, and where some
bending" comes into play. Insert the key, so that the small
end is on your left, as you face the camera, and ensure that the nib
presses on the spring clip, to release the adapter from the bayonet.
This requres some fiddling and can be difficult, as the other
may catch on the camera's bayonet flange on the other side.
it all starts to move, rotate the adapter
counter-clockwise, until it stops.
the key and then, using your fingers,
gently remove the adapter. Use care not to touch the mirror!
far, so good.
The problem is that the removal tool, or "key", is
for the job. If you press the key to the right, so that the
releases the catch, the other end jams up against the bayonet flange
and makes it very difficult, if not impossible to rotate. The
first part of the solution is to carefully bend the "nib"
a bit, which allows it to press the spring catch inwards, without
having to press the entire key to the right.
image shows the other end, and the careful
bending which has been applied. Originally, it was straight,
indicated by the white lines, with a square bend to make the "bar" more
in line with the curvature of the lens mount.
My version still sticks a bit, as you rotate the adapter out of the
camera. But, a bit more "selective bending" will probably
that. But, for now, these modifications allow the adapter to
removed easily ... something not possible when the key was new.
Let sports & wildlife photographer, David Young, help you move
from being a taker of snap-shots to a
maker of super-shots. Behind a camera for over 50 years,
David has beena guest speaker or presenter at
conventions in Germany, the USA and,
of course, Canada. Now, this wealth of knowledge and
experience is available
in a series of e-books for almost any e-reader (other than a Kindle).
Click on any e-book cover, for
Besides the Nook, Sony & Kobo
e-readers, you can read these e-books on any iPad, iPhone,
Tablet or Window's computer, using free aps from Kobo.com.
If you found this
useful, other adapter problems can be found here
My wildlife photos are here
photo instruction DVD's are here