Low resolution plus low resolution

Taking a break from lens testing to do a little lens testing.

You might have suspected that the Sony’s high resolution 24MP sensor is great for showing up any and all flaws a lens might have, and you’re right; it does.

What then would be the result of using the lowest resolution sensor I have available, the 6MP Pentax K100Ds? Not needing to reduce the image as much for “Internet size” pictures means you also can not increase it so much to spot the flaws. You can get away with a lot if you don’t look at a picture too closely!

Opticam 135mm f2.8.
Opticam 135mm f2.8.
Cunor 200mm f4.5.
Cunor 200mm f4.5.
Sun Actinon 28-80mm f2.8 (widest).
Sun Actinon 28-80mm f2.8 (narrowest).
Prakticar 70-210mm f4.5.
Prakticar 70-210mm f4.5.

As you can see if you don’t ask too much from a lens it can deliver something better than you expect. (All except the Sun Actinon, which still proves to be a very poor lens indeed.) In fairness, these images are not “straight out of the camera”; they have been processed, including ‘sharpening’, to achieve the best possible result with still a minimal amount of effort.

Re-learning curve: Pentax K100D Super

Things I like about this camera:

1). It was really cheap to buy (although most offerings of it aren’t).

2). CCD sensor. You want “film quality” images? Can’t beat the CCD sensors.

3). Uses standard ‘AA’ penlight batteries. Nothing special or expensive about powering it.

4). Pentax K lens mount. That’s a vast array of available lenses. I also have the M42 – PK adapter so I can use my classic Takumars.

5). Good control arrangements, easy to set up and use.

Things I don’t like about this camera:

1). It was used in an archaeological dig. As a shovel. This explains the price, and why I am continually cleaning it. The lens has significant coating damage on the front and I keep getting shadows on the images because more dirt is rattling around inside. It’s easier to re-touch the photos.

2). CCD sensor is only 6MP, making digital zooming an impossible dream.

3). Uses standard ‘AA’ penlight batteries which are more expensive to continually replace than just recharging a lithium set. I could buy rechargeable penlights, but that would be substantial capital outlay.

4). Pentax K lens mount limits adapting of other lenses because it is small. Fitting the M42 lenses is even tricky because the K mount is just a bayonet incarnation of the screw mount so the adapter is thin, fragile, and not always easy to get in place.

5). The shutter button focus has failed, causing some significant problems for me because I can’t tell if the image is focused and forget to push the ‘wrong’ button.

6). In addition to the internal and external dirt problems, some of the silver has come off the pentamirror so the viewfinder presents black splotches. My eyes have their own black splotches now, thank you, and I don’t need to see any more.

The ultimate question is: how well does this camera fit with my current photographic plans? This we evaluate on a basis of two criteria: usage and results. Usage … well you’ve seen the clues above. The viewfinder issue is more than a little vexing, and the back-button focus requirement has resulted in far too many out-of-focus images. Add to that the lack of digital zooming ability due to the low resolution sensor and subtract the fact I can adapt the Takumars to one of the Canons (and more easily) and you see it fails for usage.

Now what about results? As with all the equipment under my “new” eyesight, the percentage of “good” to “bad” pictures is disappointing. For the other cameras this has been a matter of me re-learning. In the case of the Pentax the camera itself presents faults which can not be overcome. It would be better if this were an excellent example of a K100D (without the silver loss and focus problem), but it isn’t. I could replace the lens, but should I bother?

Let’s look at the pictures:

Rusty rhubarb.
Lavender weed.
Typical sky shot.
Suddenly a raven. I fired off half a dozen shots trying to get this bird in frame and in focus!
Pale moth. (Notice the lack of sharpness due to the lens.)
A look at the lake.

Over-all I’d say the results are good, maybe only fair. Changing the lens helps (I have another series coming re that), but nothing can be done about the 6MP limitation on getting closer after the shot was made.

This is a camera I should sell. The question mark hanging over that is: would anyone buy it? If not, I have no problem keeping it. It doesn’t take up much space and is unlikely to get any worse from sitting unused.