The Best £15 You Can Spend On Your DSLR

My first DSLR was a used 2009 Pentax K-x, in 2014.

At this point I’d already been shooting film SLRs a couple of years and had fallen for a number of vintage manual aperture, manual focus lenses, like the peerless Takumars, and the Helios 44 series.

In researching DSLRs, I was delighted to discover that Pentax had retained their K mount since its introduction in 1975, so any K mount lens could be used on a modern Pentax DSLR.

Lenses like the excellent Pentax-M 50/1.7 and the humble yet frequently impressive Ricoh Rikenon 50/2.

I also found out that with a simple adapter ring, I could use the older M42 screw mount lenses I mentioned before on my DSLR. 

However it wasn’t unbridled happines from the outset.

The cheap adapter I went for gave me issues with infinity focus (it protruded from the camera body, so the lenses wouldn’t mount flush against it), and I was baffled at first by why my lenses on the DSLR seemed to be “zoomed in” much closer than when I used them on my film SLRs.

Further learning revealed that because the APS-C sensor in the DSLR was smaller than a frame of film, there was a crop factor of 1.5x.

Meaning that a 50mm lens on a 35mm film camera gives you an equivalent 75mm field of view (ie 50mm x 1.5) on a DSLR.

In time, I shot more with a DSLR than an SLR, so the focal lengths and fields of view just became normal to me, and it was no longer an issue.

On the adapter front, I later bought an official Pentax version, which still only cost about £15, and fits inside the camera mount, so lenses fit flush against the body, as they should.

And, arguably, this is the best £15 I have spent on my Pentax system, because it lets me use all those classic M42 lenses I own (and have owned – and thousands I (yet) haven’t).

Many of the Pentax K and M series lenses are almost as lovely as their Takumar predecessors, as well as being optically excellent.

But being able to use the beautiful Taks, plus other lenses that there is no direct equivalent of in Pentax K mount – like the Carl Zeiss trio of the Flektogon 35.2.5, Pancolar 50/1.8 and Sonnar 135/3.5, the Helios 44-2 85/2 with its unique bokeh, and the Jupiter-37A 135/3.5 I recently fawned over here – make the adapter an essential purchase in my eyes for any Pentax DSLR owner.

Indeed, a number of other digital camera systems have M42 adapters available too. 

I’ve shot M42 lenses on Sony A mount DSLRs, a Sony NEX 3N and a Panasonic Lumix GF1. It’s an excellent investment that opens a world of opportunity.

The photographs in this post were all made with a Pentax DLSR and M42 lens.

How about you? Have you used M42 lenses on a Pentax DSLR – or any other digital camera? 

Please let us know in the comments below (and don’t forget to tick the “Notify me of new comments via email” box to follow the conversation).

Thanks for looking.

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