Keep using those M42-mount lenses on newer non-M42 bodies

 As I have written here often about M-42 mount lenses and cameras, you know how I love those Pentax Takumars.  There are many thousands of them in circulation, and most of them are still in good working order. The same can't always be said for M-42 mount bodies.  Meters die, shutters get old and cranky, and just because of age and abuse, those lovely (and some not so lovely) M-42 mount bodies can become unreliable.  Some are really heavy, too, which negates the benefit of those Takumars. 

When Pentax released their K-mount bodies, they also sold M-42 to K-mount adapters. Everything was the same as far as flange distance, so you could still keep using your screw-mount lenses on the Pentax K bodies.  However, that only allowed you to use the lens in manual stop-down mode for metering -- which you were probably already doing with a Spotmatic. So that's not a big drawback to their use.

Fast forward to today, and the best replacement would be to use one of the Vivitar V3800N K-mount bodies, which are relatively recent, as SLR bodies go.  Those bodies also appeared as other brands, such as the Promaster 2500 PK Super.  You get a lightweight body, red/green diodes for the metering, a top shutter speed of 1/2000 sec, multiple exposure capability, self-timer, a PC and shoe flash ability, and depth of field preview - because you are shooting in stop-down mode.  

The M-42 adapter in place

Be sure to move the aperture switch to Manual

Look at that beauty.

Another option is to use a Minolta Maxxum 7000 - which are plentiful and cheap.  You can find a Sony Alpha to M-42 mount adapter, and shoot in Aperture Priority or Manual modes.  Just like that, you have an M-42 mount camera with auto film advance!  Other Minolta AF bodies may also work well with the M-42 adapter, but I have not tested them.  Again, you'll need to use the lenses in Manual, not Auto mode, so they might be a bit dim for focusing in low light conditions.

There are other M-42 mount adapters for other bodies, such as Nikon, but they don't focus to infinity. Sticking with a K-mount body and M-42 adapter is the logical choice, especially if you already have a camera such as the Pentax ME.  However, the Vivitar 3800N remains a very good and inexpensive option to continue using the wonderful range of screw-mount lenses. on a small, lightweight body with modern electronics.

Of course, there are mounts for the latest mirrorless digital cameras, but we are talking only about using film cameras here.  The M-42 Pentax Takumar lenses are compact. I have a kit with a 50mm f/1.4, 24mm f/3.5, 105mm f/2.8, and a 17mm f/4 along with a Spotmatic F, filters, etc. and it occupies about 2/3 space  and weight that a Nikon kit has with similar lenses.  

So, give those old Takumars a new life with a newer body, and adapter.  You'll quickly realize how nice those old lenses are.