Why Q?

[Bill De Jager]

This topic might seem to go under Camera Talk, but ultimately it's about lenses.  The camera under consideration, for me, is merely a route towards ultimately using interesting lenses.

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The Pentax Q system, when it came out, seemed eminently worthy of being ignored. Why have a mirrorless camera system with a sensor no larger than that of a compact camera?  The fact that some of the lenses were actually labeled toy lenses by the manufacturer merely made the system seem even less worthy of being taken seriously.  Like many others, I proceeded to studiously ignore this system for years. 

There was even more reason to ignore this system once it was discontinued.  Why buy into a dead system with a major inherent and unfixable shortcoming, sensor size?  Why buy into this system, when I have a μ4/3 system camera (Panasonic GM5) with a sensor having four times the real estate yet in a body no larger?

Well, I did anyway.  Why is a story for another day in this thread. Certainly the end-of-life prices were much more reasonable than when the system was being promoted!

So here's what I got: 

-The latest body, the Q-S1, 12MP, with a 1/1.7" sensor (7.6 by 5.7 mm) having a 4.6x crop factor.
-The "01 Standard Prime", 8.5mm and f/1.9 (a 35mm lens having an equivalent field of view would be 39mm)
-The "06 Telephoto Zoom", 15-45mm and f/2.8 (a 35mm lens having an equivalent field of view would be 69-207mm)

Here is the body and the two lenses, compared to the Panasonic GM5 and lenses having the equivalent field of view (Panny 20/1.7 and 35-100/2.8 ).

Q-S1 and GM5 by Bill de Jager, on Flickr

The Q-S1 is no smaller than the GM5, but you have to concede that its lenses are far smaller than the closest equivalents in the μ4/3 system. Of course that's at the cost of reduced sensor performance and reduced control of depth of field.

So how does this system perform?

Magnolia by Bill de Jager, on Flickr

Trunks by Bill de Jager, on Flickr

Young Tree by Bill de Jager, on Flickr

Well, competently for a compact camera which is all you could really hope for.  There's even bokeh with the telephoto zoom.

So what?  That's reserved for the next post. 


 

[Bent Hjarbo]

I had the same thoughts when I saw the Nikon 1 introduced.
But when I got the chance of testing it for a weekend with my normal Nikkors I ended buying a set with two lenses and the F adapter. Later came the CX 70-300 and it has worked will for "wildlife".
The camera may not respond as fast as my DSLRs but is very travel friendly. With some care the files can be ok, and sharp.
So something that looks ridiculous at first sight, may actually be of use if it offers something useful.
Unfortunately the start-up time makes it not very good for street photography.

[Bill De Jager]

Bent, I certainly considered the Nikon 1 but I ended up passing on it for a variety of reasons.  The Pentax Q bodies, at least starting with firmware version 1.1 on the first body, has been better suited to adapting manual focus lenses.  You can easily enter the focal length, and the bodies have focus peaking and in-body image stabilization.

I had one more shot taken with the 15-45mm:

Plum Buds by Bill de Jager, on Flickr

One thing I forgot to mention is that with this lens you have a pretty decent telephoto capability in an extremely small and discreet package, albeit one best suited for good light.

[longzoom]

Looks like it is very capable combo in your hands! LZ

[Bill De Jager]

Thank you, longzoom!

Sometimes ideas take root slowly.

But first, a digression. When I was last in college I had a noteworthy roommate. Louis was a big fan of cars in general and of high-horsepower sports cars in particular. He was an engineering student who fervently hoped to go into automotive engineering eventually. One day he read of a car with 800 horsepower and he reported this to me with tremendous excitement: "Bill, that car has 800 horsepower.... 800 HORSEPOWER!!!"

So what does this story have to do with cameras and lenses? Well, I've long used this site (just now taken down so accessed through the Internet Archive) as a very useful reference when figuring out whether lenses can be adapted to another mount while still retaining infinity focus. This table is particularly useful for plotting the testing or use of old lenses for their potential or known value in digital ultraviolet photography, where one is seldom using a lens on its native mount.

This table definitely steered me towards investing in a Sony A6000 (register distance 18mm), which is now converted and ready to test short-register lenses. But note at the very top left the entry for Pentax Q: 9.2mm. It's like my old roommate all over again...9.2mm....9.2MM!!!  Maybe this camera would provide a way to use lenses that wouldn't provide full focus on a Sony E-mount.

Now to get that 9.2mm you have to make some compromises such as a very small sensor and all that means in terms of performance. You also won't really get that 9.2 mm because you'll probably have to use stacked multiple adapters.  That's if you can even find adapters that don't 'helpfully' provide the correct register distance which you really don't want when stacking adapters to use obscure old lenses! Still, this system seemed to present some promise.

Hence, this:

Stecky 40 and Rodenstock 95 by Bill de Jager, on Flickr

One of the fun parts of playing around with old lenses is creating Frankencameras - monstrosities that may be ugly or even scary but which can also be intriguing or even amusing.  These creations may even produce worthwhile photographs on occasion.

On the left, one Pentax Q-S1 body has mounted on it a Steky 40mm f/5.6 lens.  What's that???  Here's the camera and the lens.  This subminiature camera from post-war Japan used 16mm film.  The lens mount is a [EDIT: n unknown screwmount screwmount of 16mm with a pitch of 0.5mm] which will screw only partway into a D-mount adapter, probably due to the wrong thread pitch.  That's then screwed into a D-mount to C-mount adapter which is then screwed into a C-mount to Pentax Q adapter, and the lens is mounted.  Sort of.  This jury-rigged setup gets close to providing enough backspacing, but the exact backspacing needed is unknown.  I ended up focusing the lens to the near focus limit on the helicoid while partly unscrewing the lens from the mount and the D-mount adapter from the C-mount adapter, all in an effort to get any focus at all.  In the end I obtained only two photos with some semblance of focus, one of which is below.

Plum on the Q by Bill de Jager, on Flickr

More testing is needed along with a longer mount. I just remembered I received a set of C-mount extension rings last week and the shortest one might perhaps be useful here. Actually, I could measure the needed backspacing by projecting an image from the lens, but somehow that slipped my mind yesterday!  And I need to buckle down and mount the camera on a tripod and be more systematic instead of just playing around.

[simato73]

So what does this story have to do with cameras and lenses? Well, I've long used this site (just now taken down so accessed through the Internet Archive) as a very useful reference when figuring out whether lenses can be adapted to another mount while still retaining infinity focus.

That's most helpful, thanks!
I was recently looking for this page from my bookmarks and could no longer find it.

[Bill De Jager]

My pleasure, Simone!

Continuing with the photo of the mismatched lenses in the previous post...

On the right we have a Rodenstock XR-Heligon 95mm f/1.4, mounted on a second Pentax Q-S1 body with a couple of simple adapter rings.  I had to remove a rear ring from the lens to uncover a usable screw thread.  Later the rear element fell out but was easily replaced.  All in a day's work... 

This lens is similar in general outline to the 50 mm f/0.75 Rodenstock TV-Heligon Bjørn Rørslett reviews here (under special-purpose lenses).

The result does focus but not to infinity.  Since I haven't yet worked out a safe support system, I used this setup handheld, moving back and forth until the subject was more or less in focus.  Between the longish focal length and the substantial crop factor, this setup slightly resembles a macro lens with a long working distance... only this is no macro lens by any ordinary standard.  I strongly suspect that the lens is not mounted at the intended backspacing due to the obvious optical aberrations.  Possibly the rear element wasn't reseated properly.  In any case, the results can be quite interesting...

Nandina #3 by Bill de Jager, on Flickr

Roden #1 by Bill de Jager, on Flickr

Nandina #1 by Bill de Jager, on Flickr

And finally, a little fun with the colors!
Nandina #2 by Bill de Jager, on Flickr

Much more remains to be done, including experimenting with C-mount and D-mount lenses and who knows what else.  I also have a Rodenstock XR-Heligon 68mm f/1? that I can't use yet because the rear ring won't screw off, leaving no screw thread to work with. I'm hesitant to use a penetrating oil for fear of fouling the lens elements. Ideas are welcome.

The Pentax Q is dead.  Long live the Pentax Q!


 

[Bill De Jager]

This weekend was my last chance to catch the plum blossoms this year.  Here again is the Rodenstock XR-Heligon 95mm f/1.4:

Plum #3 by Bill de Jager, on Flickr