Every now and then something fun happens. You run into an old friend on the street when you were just thinking about them. You remember how long it has been since you saw a good rainbow and the next day it rains and gives you a good one. That happened to me recently, an old photography friend who used Pentax gear for years contacted me about rehoming some lenses he was not using, at the time I was literally on ebay just browsing old wide angle lenses for fun. In my film days I used Canon cameras, with my trusty AE-1 Program I took a lot of fun photos and learned a LOT. When I was in Scotland in school I ran across and bought an inexpensive Vivitar 19mm lens, this one here: https://www.pentaxforums.com/userreviews/vivitar-19mm-f-3-8.html  It was my first ultrawide lens and introduced me to a whole new way of seeing the world.

When his message came up I told him I was up for a re-homing and gladly accepted the gift. Not knowing WHAT lenses he had for me, beyond a few m42 screwmount's and some other K-mount lenses. FYI K-Mount is the mount for most Pentax Cameras made after the mid 70's.

A few weeks later I met him for breakfast we had a great chat and he handed me two BOXES of lenses. I was VERY excited to see a lens I had been looking at in one of the boxes when I opened them up. The Auto Vivitar Wide-Angle 20mm f3.8 manufactured by Kiron/Kino in Japan. This lens listed here: https://www.pentaxforums.com/userreviews/vivitar-20mm-f38-auto-wide-angle.html

I had never dreamed that I would just have one just drop into my lap! I have the Pentax 15-30 f2.8 that I have talked about previouslym but I had been toying with the idea of a Pentax branded lens of the same era/series of my other old manual focus lenses as a smaller walk-around for street shooting. This one actually https://www.pentaxforums.com/lensreviews/SMC-Pentax-K-20mm-F4-Lens.html the problem being price... and finding one in good repair. So to say I was excited would be quite the understatement, as soon as I got home I immediately put my m42 to Pentax adapter on my K1 and mounted the Vivitar up.

First Impressions:

The front element is really quite large, especially for the modest aperture.

The lens is all metal and quite well made, it handles nicely and is not too big nor too small.

It can focus REALLY close, like REALLY REALLY close (More about this later)

It is not super sharp at closest focus distance and wide open (i.e. aperture not closed at all)

It gets sharper stopped down and if you back off a few inches.

I have since had it on my camera a fair amount, and I am ready to post some photos and talk about how it performs. 

My first desire when I put on a lens for streetwork is that it gives me a different way to look what I see everyday. Often my only chance is transferring from the bus to the train downtown, and maybe deliberately skipping a train so I can deviate a block or two.

My second desire from a lens is reasonable sharpness in a decent sized package. I have big lenses that are very sharp, but cumbersome, and not what I want to carry on the train for the days commute. I will trade a little sharpness, and a smaller aperture wide open for size and portability. There are far more qualified folks to talk about that than me, but those are my priorities.

This Vivitar seems to meet these criteria fairly well, I don't think it is the sharpest ever, especially at infinity focus, but it does seem to do reasonably well at medium to close distances, and the wideness helps to change HOW you see through the viewfinder.

This is at or near closest focus and wide open (f3.8) it is a little soft, however, and this is a big however. It can isolate subjects reasonably well due to the close focus, the background blur (Bokeh it is called) is not terrible and I think this lens will be quite useful up close.  

Being able to place a subject inside of it's environment is a benefit to ultra wide angle lenses, often the juxtaposition of the subject to the surrounds creates the flow and charm of the image. At medium distance and medium f number this lens is quite acceptably sharp. (IIRC this was f8 but the lens does not communicate with the camera so I do not know.)   

I photographed this sculpture many years ago, it is in an old neighborhood that I like to go back to occasionally. I played with different apertures varying the background blur, again I find the rendering acceptable, there is some light drop off in the corners but nothing too drastic. 

The drama that the lens can produce and the overall rendering work well, I do think it will become a part of my street kit.

Now, I wanted to do a little comparison to my other ultrawide lens my Pentax DFA 15-30 f2.8, so I set up a quick and dirty scene in my kitchen this morning to compare the two lenses relative to how they render wide open and stopped down and see how the closest focus compares. I found out a few things. First the relative position of the front of the lens to the subject is VERY different between the two lenses.

This is as close as the 15-30 can get.

Without moving anything but the stuffie this is as close as the Vivitar can get.

That introduced a little chaos into my test shots, but I think is illustrative of how these lenses differ in use. So I tried but ended up having the 15-30 set at 19mm instead of 20mm, but you will notice that the field of view varies between the two with the camera position untouched and just switching lenses. This first set of photos is the 15-30 @ 19mm per the lens starting at f2.8 and going smaller in 1 stop increments to f22. Notice the change in depth of field and rendering of the background. I put the focus on the first and second teeth on the stuffies smile. The only processing was to increase the exposure by one stop, reduce highlights by 50% and increase shadows by 100%, using the same preset for ALL photos.

Now all I did for this set is switch to the Vivitar, not moving anything and trying to focus in the same spot, I used the same aperture and shutter speed as the first series, though there is no f2.8 as the Vivitar starts at f3.8 (which is effectively f4) First thing I noticed was the lens APPEARS wider than the 15-30 @ 19mm. I think in part to how much bigger then 15-30 is and how close the front of the lens is to the subject.

So I put the 15-30 back on and zoomed out to 15mm, it changes the perspective a little but it is not the same, maybe a little more dramatic. 

I was rapidly losing light on the stuffies head so I re-arranged a little for one more shot at 15mm 

I then put the 20mm back on with the camera in the same position. The appearance is just that bit different isn't it. 

Now to illustrate HOW different the close focus ability makes things. All I did was turn the Vivitar to the closest distance it will focus then move the stuffy to place the in focus point in close to (but not quite) the same place as before without moving anything else. That changes the appearance significantly. I do not know the magnification ratio of this lens, but getting much closer will require some interesting lighting adaptations. If you scroll back up to the overhead shots taken with my cell phone you will see just how close this is to the front element. There is quite a bit of separation of the subject from the background and this can be quite the dramatic effect.   

I would be quite comfortable at f5.6-f8 with the balance of sharpness to bokeh at closest focus. That will likely entail higher ISO when in the shadow of buildings to keep shutter speed up to avoid motion blur, but for street stuff that is not a problem.   

f22 still isn't bad at all in regards to sharpness, but there is some due to diffraction from the small aperture.   

Overall conclusion: I like this lens, I will be adding it to my street shooting arsenal and it is a keeper. The close focusing ability combined with the wide angle of view will allow for some unique perspectives and and a different way to see the world compared to more conventional focal lengths for street shooting. From me two thumbs up!

Thanks for making it to the end, if you have questions or concerns feel free to email me: [email protected]