Mini-review: PK_Tether


Live-view or not - for some of us tethering remains an attractive technique.


First of all because it offers "instant" - well reasonably quick - pre-views on a computer screen (possibly calibrated) much larger than the camera's LCD screen. Thus, studio light settings, composition, camera settings, focus etc. can be readily checked in high resolution and camera settings can be changed without having to manually touch the camera - in certain situations a great convenience. Finally, tethering lets one save images directly on the hard disc in a pre-destined folder/library and with pre-destined file names - also often a significant convenience.


Unfortunately for us Pentax owners there are but a few models that are designed (or released?) for tethered shooting. If I remember correctly, only the *ist D-series, the K10D and the K20D have been released with the capability of tethered shooting via Pentax Remote Assistant.

(Note: I use my Pentax *ist DL happily with Pentax Remote Assistant even though the manual tells me that I can't. Not all functions are available, but enough of them for me!)


But thanks to private enterprise and ingenuity here comes a little piece of software that allows for tethered shooting with the following Pentax cameras:

  • K10D

  • K20D

  • K200D

  • K7

  • Kx

  • K5

  • Kr

 The program, called PK_Tether will be found at the following site:


from where it can downloaded as a zip file. In order to run the program program you will further need to have .NET 3.5 Framework (free download from Microsoft's download pages) installed as well. Then it is just to unzip PK_Tethered and run the program. This is a beta version and not everything works yet, but I will come back to that later.


I have tested the program with Windows XP and my Pentax K200D and can obviously only report my findings with this specific this combination.  You open the program and then connects the camera to your PC via the USB cable that came with the camera. Then you turn the camera on, the program recognizes the camera  and we are ready to go. With some excitement we take the very first picture:


One immediately notices the nice, big preview image. You can drag out the user interface to full screen size (which you cannot with Remote Assistant) and thus, you can immediately check focus, lighting, composition etc. in high resolution (and as said before, that's what tethering is all about). Of course you can also have a viewer application running in the background and control the effects of your settings in even higher resolution. For saving of images you have the following options:

  1. To save directly to disk in a predetermined folder, or

  2. To save images in a buffer and then use "save as" (Unfortunately, there is only room for two 10Mpix images in the buffer)

  3. File naming using either consecutive numbers or date and time


Now a little about what works and what does not yet work (so well):

The functions of the various buttons are rather self-evident; there is no manual with the program but really also little need for that. The following works in my set-up:

  • AutoFocus

  • Green Button feature for manual lenses

  • Settings of exposure time, ISO, exposure compensation

  • Choice of image format (JPEG, RAW, JPEG + RAW)

  • Selection of image size (10M, 6M, 2M)

  • Selection of image quality (***, **, *)

The following works only with limitations:

  • Periodic shooting (you have to fumble a bit around with intervals and exposure times for hitting such combinations that will work)

The following does not work at all with my set-up:

  • Aperture selection (I must set that in the camera or on my lens)

  • Additionally there are some buttons that have not yet been "activated" in this version of the program

 By the way, one notes that the software easily reads not only the Camera name but also the lens name (something that Pentax's own software arrogantly "refuses" to do with third party lenses!). Moreover, the software decodes the focal length, auto focus- and metering modes as well as the shooting mode - the latter shows up by the settings that are permitted and which appear with dark characters on the buttons:

 As said, this is still only a beta version that is not without shortcomings, but all in all a very convincing achievement for which Mr Tomaszkos deserves high praise.


Note for Windows 7 users: Although I have only tried PK_Tether in a Windows XP Professional environment, I have learned from others that you have to run the program with Administrator's Privileges  in Windows 7.


Addendum - PK_Tether Version 0.4.5 - March 2011
An upgrade, version 0.4.5, became available in February and can be downloaded from

For me, as a K200D user, this implies that now I may also control the aperture remotely. Other options such as Fn-settings, WB, ISO also seem to work flawlessly.

Issues with Periodic Shooting still remain to be solved - but one still have a very powerful tool for free (apart from a much deserved donation). Now I just need a small, ultraportable notebook and then it is off to the telescope........

Addendum - PK_Tether Version 0.6.4 - February 2012 (2012-02-29)
Version 0.6.4 was released on 19 February and I have just tried it on my almost new Pentax K-5 and my almost brand new Windows 7 Starter netbook.

This setup is so portable/transportable that I have finally got myself a "field" setup for better photographic "instant" control at the telescope and I expect that this could also be useful for certain applications in macro and birding - using Catch-in-Focus and continuous shooting mode. One further project idea that might be worthwhile to pursue would be controlling  the netbook and thus, the camera remotely from another PC in a wireless network. Well, I have begun looking for a wireless router.....

And the software?

Well I am happy to report that Bulb settings in all modes available:

  • Standard

  • Start/Stop

  • Timer

seem (as for now) to work without much - if any - hassle. Time will show.

Interval shooting has also improved a lot but in today's very last test session, I encountered some remaining bug: One sets the maximum number of shots, but that number was exceeded and the camera just kept on shooting and shooting.

Well, you cannot win them all - at least not in one round - but we are very fairly close now!

One final note of caution: At the start I had the program placed in the windows Program Files folder and that didn't work at all: If I used Autosave or tried to save multiple files from the buffer, the software always crashed. Moving the program to a folder in my personal users' directory  solved that problem.



Copyright 2011 - Steen G. Bruun