Komura 105/2.5, Pentor 100/2.8, and Tamron 105/2.5 Compared

[woodrim]

I had mentioned a couple of times that I wanted to compare these lenses, so have finally gotten to doing it. I very much like all three of these lenses regardless of any perceived differences in the results. If I were to use my own argument of not needing any more than one of any focal length, well, I want them anyway. I've always had difficulty with these tests seeing any appreciable differences in similar lenses, and this exercise is no different for me. Any one of these lenses will provide excellent results and near impossible to differentiate without a hint like aperture shape showing up in a specular highlight. But with a critical eye and some nitpicking, I have come to my own opinion of which lens is sharpest and which provides the better bokeh. I will not be surprised if others see it differently since all are so close. I should also mention that I must not be very good at creating these type comparisons since this was my third attempt in as many days, and I still had difficulty getting it right. I took three pictures of every scene with each lens, refocusing each time. Damn good thing I did because there was at least one out of focus in each set of three. On top of that, I foolishly picked some subjects that were effected by wind. Please don't compare the same exact point in each picture, but find the best focus points for comparison.

The Pentor was shot wide open at f/2.8 while the other two were stopped down a fraction to f/2.8 for equal f-stop comparisons, although theoretically this would create a disadvantage for the Pentor. My conclusions are that the Pentor is the sharpest lens, followed by the Komura. The Komura has the best bokeh followed by the Tamron. The Tamron wins for being the biggest lens, the Komura is the smallest diameter, and the Pentor the smallest overall.

Full sized images can be seen at pbase by selecting "original" from the size menu under the pictures. For those interested in doing that sort of analysis, they can all be found here: http://www.pbase.com/mdlempert/pentamkom The images that follow are smaller versions:

Pentor 100/2.8

Tamron 105/2.5

Komura 105/2.5


Komura 105/2.5

Tamron 105/2.5

Pentor 100/2.8


Pentor 100/2.8

Tamron 105/2.5

Komura 105/2.5


Komura 105/2.5

Tamron 105/2.5

Pentor 100/2.8

[luisalegria]

Interesting.

I have the Tokina (Pentor), and the Tamron (In Adaptamatic mount, but I think its the same lens)
I don't have the Komura - that thing can fetch a good price these days !

I thought the Tokina had an edge in sharpness, but as you say this is difficult to check.

[dimitrygo]

[dimitrygo]

[woodrim]

Lusi: If yours is the Pentor that we discussed in other recent threads, then it's most likely a Tomioka. My Tamron is the Adapt-a-matic. If I understand you correctly, then you agree that the Pentor is a little sharper.

dimitrygo: Each set of three images were taken at the same shutter speed and f/2.8. Any difference in exposure is due to lens aperture variances or the small amount of light change while changing lenses.

[Pancolart]

My wish: posting those in oversize gallery and at least 1400px per photo. Additional crops where sharpness could be assessed (leaves are ok). Otherwise i am glad again to see this subtle style of testing.

[woodrim]

Pancolart: Full sized images are available at the pbase link I provided.

Any one of these lenses will make wonderful images and will be sharp with good bokeh. It's only when put up next to each other that you might see any difference, and that is minimal. I'm seeing little benefit to these types of comparisons because when it comes down to it, it's the feel of the lens and the perceived IQ of the images after a real session that counts. My 135mm lenses have best demonstrated this point to me; if I were to make side by side comparisons, which I have with some, I might critically point out subtle differences in sharpness and bokeh and etc., but when I go out and use them, then view the results, certain of those lenses' results impress me much more than through any testing. I have loved the results from my Vivitar Series 1 against all others, but when I got the Tair-11 133mm, that all changed. The Series 1 is the sharper of the two, and has great bokeh, but the IQ, even if not easily explainable, is the most pleasing to me.

The Pentor 100mm, believed to be a Tomioka lens, does this for me also. While not to the same degree as the Tair, the Pentor seems to provide for more pleasing overall results. However, I will point out that in this case, the Pentor is also the sharper of the bunch. In testing and comparing, I give the bokeh edge to the other lenses, but still, the Pentor bokeh is very pleasing in general use. I submit this picture as an example (see below). Very crisp where wanted and a very pleasing bokeh in my estimation. I should have pointed out earlier that my camera is a mere 10mp, so keep that in mind.



and here a 100% crop:


Other of my observations from using these lenses are that the Pentor is also sharper at distance, and we should recognize that while the above comparisons were made at f/2.8, the Pentor was fully open and the others stopped down a small amount. However, I still appreciate the rich colors and bokeh of the Komura. The Komura is sharp at short and medium distances, but not as much at longer distance.

[dimitrygo]

Pentor is not made by Tomioka. I saw a Chinon 100/2.8 lens made by Tomioka and Pentor is different.

[woodrim]

Yes, there is one major difference in that the focus turns in the opposite direction, but is that all so conclusive? The similarities are greater than that one difference. However, I'm not a Tomioka freak, so don't really care other than would be good to know one way or another. Perhaps if someday one of us has both we can evaluate better.

[Pancolart]

Sorry Woodrim, didn't read all text and missed your link. Cool.

Otherwise i also think Woodrim has Tomioka clone whereas Tokina made that Vivitar T4 styled one.

[dimitrygo]

[woodrim]

[dimitrygo]