13 May 2016

A match made in heaven

Among my many camera lenses I've owned or used, there is one lens that stands out as nearly impossibly good. Devine.

The 7:6 lens diagram designed by Mr. Yasunori Arai.

It was developed at Asahi Optical Company (aka Pentax) by Mr. Yasunori Arai and a few days ago it was 32 years since the final design patent passed: the SMC Pentax-A* 135mm f1.8. Mr Yasunori also designed the big gun SMC Pentax-A* 1200mm f8 ED IF. Judging from patents, he spent a great deal of his time working on Pentax astronomical lenses, especially how to minimize chromatic aberration in them. Perhaps this is why the A*135/1.8 does so well in that regard. If any reader knows more about Mr. Yasunori, or even have a photo of him for my page of Pentax lens designers, I would be most obliged.

The Super-A camera came in 1984, and with that the A serie of Pentax lenses, which is perhaps the most ambitious of their lens lines. I got my Super A in 1984, but it would take almost a decade before my copy of the A*135/1.8 found a home with me. By then autofocus had arrived and "destroyed" photography for ever. Seamingly intelligent persons sold of their excellent manual lenses to afford often mediocre autofocus lenses. To my benefit.

I was making one of my usuals tours on the streets of Stockholm shooting people, when I came by the camera shop "Sergel foto" andout of habit, I took a look in the window with second hand gear, and my eye cought the sight of an exceptionally fat lens. I entered, and asked the staff to let me take a look at that lens.

Probably I had been given a broshure with Pentax complete lens line when I bought the Super A, but lenses like this had never entered my plans to own. The weight. All that glass! The impossibly large front lense and gigantic apperture opening that appeared to suck in light... They were asking for 3500 Swedisk kronor, a fraction of its price as new. Still a lot of money for a graduate student, but I had recently got a 5 year position with a real salary and had some savings from pictures I've sold.... I had to have it. I could eat porridge and onion soup for a month!

I never regretted that.

I've shot a lot of film through that lens. Streetshooting, theater and conserts....weddings. Eventually I came to use it on my digital Pentax SLRs, but these were cropped sensors, and while it is an exelent and very fast 200mm eqiivalent on APS-C, it was a pitty I could not use its full image other than on film.

1984 meets 2016 thanks to Pentax backward compatibility.

 Then came finally Pentax with a full frame DSLR. And of course the A*135/1.8 was on the priority list to try out on the new Pentax K-1. I don't think a viewfinder has looked this bright since I used the same lens on my Super-A. So far I've only had the camera about a week...but here is some first samples shot in our garden with the A*135/1.8.

Cow lips at f1.8.

Goldilocks in deep thoughts. f1.8.

Cherry flowers at f4.

Cherry flowers at f2.8.
Cherry flowers at f1.8.

I just love the colours and the buttery smooth bokeh of this lens. But the most unusual thing about it is that it stays sharp even wide open. Most really fast lenses becomes soft wide open This applies for example to most 50/1.2, 85/1.4, 135/1.8 or 135/2 by all lens makers. It appears more or less to be a natural law. But the A*135/1.8 stays sharp wide open. Yes, the out of focus areas are soft, as they should be, and at f1.8 these are large as the depth of focus becomes very thin. But if you zoom in, you will see that areas that are still within the DOF remain razor sharp. Look at my daughters hair for example!

The three cherry flowers pictures illustrates how the bokeh change when the apperture change. At f4 it is still quite bussy with smeared details. At f1.8 the whole background is smooth. This one can of course use to control the character of the image.

Today the lens is worth about 2000 Euro. The time is over when we look down on great optics just because of its manual focus. So even as an investment it was a good buy. The price of course reflects the quality of the lens, but also its scarsity. Presumably, only about 800 civilian copies were produced for the whole global market, plus a small number of camouflaged coloured copies for the Japanese self defence forces.

9 May 2016

Saving my DA*50-135/2.8

A while ago I had to put my belowed SMC Pentax-DA* 50-135mm f2.8 on the shelf. When unpacking it from my back bag I noticed an unpleasent noise. It rattled like glas against glas! I was sure I hadn't handled the lens or the bag careless, but others might. Visual inspection revealed that a lens element was loose inside the lens, and with it, what looked like a rubber or paper ring. On the shelf until I know what to do... This lens is one of the SMD lenses where some have reported that the in-camera-driven focus have froozen. But that was not the problem here.

Removing the first double element was easy (don't try this yourself unless you have the right tools). The third element was a bit trickier, but it worked. This exposed the loose fourth element. Inspection showed it to be OK: no marks on the glas or coating. The ring I had seen through the glass was of paper, it seamed. Unfortunately it had been torn...probably because I had been zooming or focusing before I noticed the damage (the last shots with the lens are optically very strange). I removed also the next element to check if it was damaged, but not from what I could see.

How to fix this? The top three elements were all fixed with two threaded rings. But there were nothing similar for the loose element. And the paper ring? I couldn't figure out where to put it, and since it was thorn...I thought it unlikely that it would stay in position. So after feeling around a bit I tried a carefully weighted amount of violence and pressed the fourth element downward into the lens....and with a "click" sound it got stuck in position! Testing it...things moved OK. I replaced all other parts...except for the thorn paper ring. And focusing and zooming worked. Shots was sharp again, and no longer a strange difference between the corners! I've saved a lens with excellent optic (in the mid range around 60-120mm its close to the best primes)...though obviously the build quality could have been better!

6 May 2016

Where to begin...

Searched through the shelves and cabinets today to gather all my full frame Pentax lenses with autofocus. Its logical to begin there. And the manual focus lenses are so many more. The picture collect all of them except for some Pentax-F lenses, and the Sigma lenses. So it is mostly FA lenses, except for the F fisheye zoom, my only FAJ and the DFA 100mm macro. Missing is also the DA 50mm...that should be a full frame despite the "DA". The K-1 is accompanied by my two best autofocus film boddies, the Z-1 and the MZ-S. So its a fully full frame team.

I've taken some first shots with about a third of the lenses today and yesterday. No formal tests yet...just shooting to get a feeling for the camera. Generally, the autofucus is very fast. It must be the largest step in autofocus speed since between the K-7 and the K-5 (going from K-3 to K-1). The camera is also a very fast shooter. Easilly end up shooting several more shots than intended when I press the shutter. Must learn to avoid that, considering the picture size, or I will ruin my self on the back up HDs. Must try some BIF with the K-1....and DIF (Dragonfly in flight).

It is wonder to see again how wide the lenses really are. Even 28mm is again a wide angle. The FA 20-35mm, and the FAJ 18-35mm gives vertigo in the short end. The normals are again normals, not portrait lenses. But I've kept shooting enough 35mm film to not have forgotten. The strange swiwel view screen comes out really handy for macro...and also for street shots! If the construction hold for field work, it can turn out a genious move by the designers. I'm trying to get used to the new third wheel....and trying to figure out the fast way between auto and manual ISO. Probably I should read the manual. ;)

Just a short on my Sigma lenses, since some have reported problems with Sigma lenses on the K-1. This is probably due to Sigmas habit of backward-engineer the communication scheme etc to each brand, and their habit of giving several different lenses the same model ID. But my copies of the Sigma 20mm f1.8 and the Sigma 180mm f3.5 macro 1:1 focus very well on the K-1. So do my ancient Sigma AF 400mm f5.6.

4 May 2016

Worth waiting for....

To paraphrase Carlsberg: Worth waiting for...
It was a long wait, but now is all forgotten, Pentax!