GH4 to Pentax K lens 'auto' adaptor?

left eye wrote:

left eye wrote:

I have a couple of Pentax Limited primes: the DA 15mm and the DA 35mm Macro,

and would like to use them on my GH4, but as they do not have an aperture ring, I would loose aperture control if using a cheap m4/3 to K adaptor.

Are there any 'automatic' adaptors available? - i.e. that would allow in-camera control of the Pentax lens aperture (and maybe also autofocus - though that not essential).

Otherwise are there any basic 'non-auto' adaptors that you would recommend for quality?

I'd be using my Pentax lenses for film, mainly for the true manual focus they provide.

+ excuse my ignorance, these adaptors have aperture control, which is for?? - especially if there is no electrical connections to the camera involved?

The following allow you to control aperture value like a on-lens aperture ring. There is a small coupler on the lens' side of the adapter, by which you can turn the aperture control ring (manual control) to open up or close down the aperture blade. However, it is purely on approximate bases and can't set the exact f/stop value as you can select through a compatible camera body or having an aperture ring on the lens.

https://www.amazon.co.uk/Kiwifotos-Mount-Adapter-Aperture-Control/dp/B0051GUJ2C/ref=pd_sim_sbs_421_2?ie=UTF8&dpID=41fnJYxuNfL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=X2ME4AXYQD72WPE8RPTA

The following is a simple flange distance adjuster allowing you to mount the lens, having the required flange distance of the lens to project a sharp image on the sensor.

https://www.amazon.co.uk/Fotodiox-Adapter-Aperture-Digital-Panasonic/dp/B0048AG03Y/ref=sr_1_4?s=electronics&ie=UTF8&qid=1462963893&sr=1-4&keywords=Micro+4%2F3+Adapter+Pentax+K

is this feature an advantage with Pentax lenses without an aperture ring?

Both don't have electric connect (so no direct communication) between camera and the lens and so it would still be a 100% manual operating lens. Fortunately, for M43 camera, by the live view we can see the lighting condition when turning of the aperture control. So know exactly what f/stop be selected becoming less important.