[Robin58]

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Oh Pentax, you have let me down....not in an earth shattering way, but very slightly in your backward compatibility. I started with a Pentax SV in 1964, upgraded to a Spotmatic then went through practically all the 35mm Pentaxes bar a couple - didn't bother with a K1000 or an MX. Finished off with the ultimate Pentax 35mm SLR IMO - the LX - before changing my allegiance to Canon - partly because I started working for them in 1987 and I subsequently got a great staff discount on both cameras and lenses, but also because the EOS system had just been introduced. It was only natural to continue with Canon when their FF DSLR's came out because all my Canon EF lenses continued to fit. I still hankered after a Pentax FF DSLR though. Anyway, one accessory I purchased somewhere along the Pentax way (probably the 1960's) was a Pentax right angle finder. It fitted every Pentax I ever owned right up to the LX. However, my beef is that it does not fit the K1!

To praise Pentax on one aspect of backward compatibility however, I have to say that all the 4 Pentax K lenses I still have that I purchased after buying a Pentax K2 around 1975, fits and works perfectly on the K1 II - except in having to use manual focus of course. I also bought, in the 60's, an M42 screw fitting Bellows II/Slide copier unit, which I later adapted to fit my subsequent K camera purchases. I adapted it to fit my K2 years ago by purchasing the M42 to K adaptor - which allowed all the K bodies I purchased later to be fitted to it as well. However, one small problem with the arrangement back then was not finding an adaptor to fit a Pentax K bayonet lens to the M42 screw fitting on the bellows, which would allow me to use the bellows for close ups and also to continue using the slide/neg copier. I overcame that by making one myself....by mating an M42 T adaptor with a suitably modified K lens cap (see photos - but bear in mind everything attached to the K1 II is between 40 and 55 years old and is obviously showing it's age. It all works however!) Anyway, just one more moan about my big disappointment. I'm disappointed that ,after fitting every Pentax I've ever owned before the K1 II, the right angle finder does not fit the eyepiece of the K1 II body! OK, it won't kill me, but to rub salt in the wound, it fits all my Canons!

For anyone interested in fitting a K bayonet lens to M42 screw fitting item such as old bellows units or old screw fitting extension tubes etc.) the following photos show how I did it. The first image is of the complete assembly - K1 camera with a K/M42 adaptor fitted (readily available from many outlets,) the bellows, then the home made M42/K adaptor (which can also be used together with the M42/K adaptor as a manual 22mm extension tube BTW), followed by the lens and finally the slide copier. The second image shows how the camera and lens can be used together for extreme close ups, image 3 is of the lens and home made adaptor on their own and 4+5 shows the home made adaptor on it's own. Of course everything is manual except that I have found the K1 II will show in LV a correctly exposed image with the aperture closed down. Any question on making the adaptor, please ask.

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[Not a Number]

Thanks for sharing. That is certainly one way of doing it.

Of course if you don't own a screw mount bellows already you may as well buy a K-mount bellows and use the screw mount adapter for your M42 lenses. If you get the K-mount Auto Bellows you can focus and compose wide open and stop the lens down using a cable release or the DOF preview button on the bellows.

[jbinpg]

Thank you for this. I have an old M42 bellows with slide adapter and a closet or two full of slides so this will come in handy.

Jack

[Robin58]

Thanks for sharing. That is certainly one way of doing it.

Of course if you don't own a screw mount bellows already you may as well buy a K-mount bellows and use the screw mount adapter for your M42 lenses. If you get the K-mount Auto Bellows you can focus and compose wide open and stop the lens down using a cable release or the DOF preview button on the bellows.

Thanks for your reply Not a Number. I have found that if I use 'Live View' and Tv on my K1 II with the bellows/slide copier set up, I get the equivalent of wide open aperture viewing because the camera auto compensates for the small aperture I choose by selecting a longer shutter time. It makes focusing easier too. Auto bellows certainly come into their own when viewing through the viewfinder though.....as did the right angle finder I used to use on my older Pentaxes. Sadly, as I pointed out, it doesn't fit the optical viewfinder of the K1 - but then my old film Pentaxes didn't have Live View either!

---------- Post added 09-28-18 at 03:01 PM ----------

Thanks for your reply and interest jbinpg. As I have pointed out in my reply to Not a Number, a Pentax with 'live view' can view the slide being copied on the LCD screen, at a stopped down aperture, with what appears to be similar to what open aperture viewing would be on the OVF. Mounting the whole assembly on a tripod makes life easier as I have shot some slides at long exposure times, although to be fair, any movement in the camera would be the same movement at the slide copier end. Good luck with adapting your M42 bellows to a K bayonet fitting camera. I have not tried the set up with an APS-C camera, let me know how you get on if you do.

[Not a Number]

Since my K10D doesn't have LiveView I tend to forget about this option on later bodies. And the tilt screen on the K-1 and other bodies is a great feature. I have the Refconverter M which finds on any of the M and later bodies including the DSLRs.

I think OpTech makes metal rear lens caps for K-mount. Perhaps even better would be to buy a set of the $6.00 k-mount extension tubes and use the front bayonet part. This just screws on to the tubes and has a locking pin. The locking pin would be better than potential damage to the flange by a screw.

Macro Extension Tube Ring for Pentax PK K Mount Kx Km k7/5 K200D K100D K20D K10D 713095316948 | eBay


You could maybe glue the front piece on to a cheap m42 extension tube instead of a T-adapter.

[enthdegree]

How much does does your lens cap construction increase the flange distance?

More directly, do you get infinity focus in the following setup?

(m42 body)>(your adapter)>(PK lens)

To me it looks like the remaining portion of the rear lens cap is acting as an extension tube.

[kypfer]

Further to the bellows idea ... B.P.M. (in the UK) used to make a "Universal Bellows Unit" with, believe it or not, interchangeable mounts! Perfectly practical to have a K-mount at one end and an M42 mount at the other, or virtually any other combination. The unit was even supplied with a basic slide-holder to clip onto the bellows rail

[Robin58]

How much does does your lens cap construction increase the flange distance?

More directly, do you get infinity focus in the following setup?

(m42 body)>(your adapter)>(PK lens)

To me it looks like the remaining portion of the rear lens cap is acting as an extension tube.

Sorry for the long delay in replying enthdegree - Covid has been a nuisance in that respect. As I only use the adaptor I made for fitting a K bayonet 50mm lens to an M42 bellows unit, the flange distance is immaterial as I merely reduce the bellows length by the same amount as the thickness of the adaptor. As to your second question, I don't use an M42 body, nor have I used the adaptor directly between camera body and lens. It fits between M42 bellows and K bayonet lens. And finally, yes, if you were to place the adaptor between body and lens, it would act exactly like an extension tube - probably close to a number one at around 12mm. Thanks for enquiring and I hope I've answered your questions.

[Kingman]

Wow...some folks are very imaginative

[JimJohnson]

Wow...some folks are very imaginative

Photographers have been building gear to fit a specific need for a long, long time. The good stuff that has more universal use often becomes a commercial product. There is a DIY sub-forum on Pentax Forums that is worth browsing.

@Robin58 did a good job with tools at hand.

[Robin58]

Photographers have been building gear to fit a specific need for a long, long time. The good stuff that has more universal use often becomes a commercial product. There is a DIY sub-forum on Pentax Forums that is worth browsing.

@Robin58 did a good job with tools at hand.

Interestingly, regards your comment about some ideas being taken up commercially, I once submitted a modification to Durst for their M605 enlarger and it was taken up by them in future models. I remember receiving a voucher from them towards any other Durst product.

[stevebrot]

It fitted every Pentax I ever owned right up to the LX. However, my beef is that it does not fit the K1!

If if won't fit the LX, it won't fit any Pentax K-mount body except for the K-series where the viewfinder was carried over from the M-42 cameras. The same shift in fit is true for all Pentax eyepiece accessories.


Steve