[Lowell Goudge]

What I have found helpful are the various lens club threads and the Lens Sample Photo Archive. Between the two, one can usually find a variety of subjects for a particular lens model as well as truly sterling examples of the lens at its best. There are currently 450 threads in the Lens Sample pool and 133 lens clubs, many of which are dedicated to particular lens "families". In the last few weeks, I have been filling adding some of my own shots to the sample pool, adding new threads where needed with the intent of providing photos showing what a particular lens can do without intent to show weakness or faults. Anyone can make a lens look bad, but it is very difficult to pull off technical magic with a lens that sucks.

Lens Clubs - PentaxForums.com

Lens Sample Photo Archive - PentaxForums.com

BTW...The index threads may be very out-of-date. I find it easier to do an alphabetical sort by thread name in the main sub-forum.

steve

except that i need to fix the format of some of the threads, AFAIK the index is fully up to date, the only issue is that the forum no longer automatically displays the thread title when linking the URL, so i have to edit them manually, i am slowly working through this task

the bigger issue is some of the early posters have deleted the uploaded photos from the forum,

[stevebrot]

the only issue is that the forum no longer automatically displays the thread title when linking the URL

I guess that explains why I was unable to find a few existing threads on the index. Thanks for the information and for your volunteer effort in maintaining this resource.


Steve

[buberfan]

@buberfan: What were your conclusions after all your testing?

Haha, yes I deliberately didn't put in my conclusions in my original post because I wanted others to come to their own conclusions.

But a few general observations:

1. All of the lenses are good enough, and in the right hands are capable of producing outstanding images. Yes, some are sharper than others, but unless you are planning to produce very large prints (or are a pixel peeper) they are all sharp enough.

2. In the light of the above point, other aspects (than image quality) are just as important: - ergonomics; ease of focusing and aperture change; aesthetics (how the lens looks on the camera). For example, the Yashinon 5cm f2 scores highly here - a great looker with a construction and smooth focus pull that puts it right up with the best Takumars. Similarly the Volna 1.8 scores well for being a K-mount. and the Pentax-A lenses get points for the camera aperture control.

3. Sample variation probably plays a big a role.

4. My three Helios 44 lenses all share excellent centre sharpness, colour, and cats-eye bokeh a the edges of the frame (which give rise to the famous Helios swirl). Before doing this test I would have put my 44-3 (which I've had the longest) at the top. But the 44m-7 is better optically, and the 13-blade silver version is very close behind it. I'd be interested to get hold of the K-mount version and compare.
5. Lenses I'll definitely be keeping for their distinctive bokeh are the Helios, Primoplan and Takumar sonnar design (58/2) - though the test shots don't always show this bokeh at its best.
6. Yes, the Trioplan 50 produces distinctive bubble bokeh, but to maximise the effect, a crop camera (or extension tubes) would be better than full frame.

7. The prize for sharpness goes (not surprisingly) to the Pentax-F Macro, closely followed by the DA*55 and FA43. I'll be keeping all three.

[cyberjunkie]

Haha, yes I deliberately didn't put in my conclusions in my original post because I wanted others to come to their own conclusions.

But a few general observations:
...........................

I fully agree with practically everything you write.
I don't own the DA* 55mm and the 43mm Limited, though.
Never used the old 50mm Takumar too. I'm not even sure I own a Sonnar-type 50mm, Takumar or of other provenance.
I have the same liking for one of the most unsharp fifties ever, the Primoplan. Even stopped down a little it still has plenty of "character".
I also confirm that one of my most loved designs, the Meyer Trioplan, is not the same soap bubble master in its 50mm incarnation, as the longer focals.
Using it with tubes, or at least on APS-C, is a sensible suggestion. The Fujinon 2.2/55mm, the only Unar-type fifty I'm aware of, could be a cheap alternative. Not much sharper, though
The Pentax-F 2.8/50mm Macro is probably the sharpest lens I own. Amazing, despite the age, and with a solid build under the plastic hood.
Your consideration about ease of use (PKA objectives) or ergonomics/build quality are also very true. The "feel" of a lens heavily influences the final outcome.
The number of diaphragm blades is not as relevant as it is believed to be, IMHO. I shoot certain lenses almost always wide open, so the number of the blades makes no difference. More relevant is the fact that lenses with plenty of blades are usually preset design, which allows for quicker operation, not affected by oily blades.

I appreciated your effort, and I will go back to it to check the images more thoroughly.

Regarding the issue of cat's eye bokeh, I believe it's all about mechanical vignetting.
I want to check soon if it's fully true. Once I find a scene that provides plenty of out of focus highlights close to the borders of the frame, I want to use one of those 4-elements 35mm designed in the fifties, with small max aperture (f/4.5), and see if a lens with VERY SMALL iris and relatively large front element (with the lens barrel shaped accordingly to the design), would show no deformed circles of confusion.
I am waiting for a Steinheil Culmigon 4.5/35mm, but anybody who owns a Meyer Primagon 4.5/35mm or the Enna Lythagon 4.5/35mm can try to check in first person. The three lenses are very similar.
Just an idea, I want to see if my hypothesis true...

[Breakfastographer]

Haha, yes I deliberately didn't put in my conclusions in my original post because I wanted others to come to their own conclusions.

But a few general observations:

Thank you. Sounds like you're still keeping quite a lot of these lenses.

[cyberjunkie]

Regarding cat's eye bokeh, I have noticed that a very sharp lens like the DA* 55mm does not get rid of deformed circles of confusion even stopped down quite a bit.
The old 1.2/50mm shows no such problem by f/1.6.
Interesting...
I guess it's not so surprising.
The DA* was designed for APS-C. The old f/1.2 had to cover 24x36mm.
The size of the front glass seem to suggest otherwise, at least at first sight... which makes me think that is more a problem of mechanical vignetting (barrel design), rather than an exclusive function of the optical design.

It seems that forum users have different opinions on this subjects, and that some prefer to see pictures with a higher iconographic value, not dumb test pics.
Though I still believe that a well chosen test subject can highlight important characteristics of the different optics, and guide the perspective buyer to a more informed purchase.
It is also good food for thought for those, like me, who are interested in vintage optics, and see them not only as collector's items, but also as usable picture taking tools.
The critical examination of well though test pictures con provide a lot of information that would likely be hidden in "beautiful" photos that are not meant to highlight the "optical signature" of the lens.

[kernos]

The critical examination of well though test pictures con provide a lot of information that would likely be hidden in "beautiful" photos that are not meant to highlight the "optical signature" of the lens.

Part of the optical signature is how the lens renders contrast, both black and white and color. Its hard if not impossible to test for, but you can see differences if you look at a large lens sample on flickr particularly for portraits and also for flowers where minute changes in color rendition tend to make the photo more alive. If you look at 20 natural light portraits of a single lens, you can see whether a lens produces this pleasing result. You can also see what other photographers think about a lens for portraiture or flower photography by trying to find 20 example natural light portraits as its a vote on whether a photographer is willing to invest their time with a lens (with the exception of rare lenses that are going to have only a few acolytes). So, until someone manages a test for this , "beautiful photos" are really the only way to understand this.

I agree that an objective test like buberfan's is interesting, but it doesn't tell me much about whether I would actually want to use a lens. I can see the bokeh represented, but it doesn't tell me if the bokeh is going to be meltingly beautiful behind a person although it does point to bokeh that would be wildly interesting in its own right.

[photoptimist]

Regarding cat's eye bokeh, I have noticed that a very sharp lens like the DA* 55mm does not get rid of deformed circles of confusion even stopped down quite a bit.
The old 1.2/50mm shows no such problem by f/1.6.
Interesting...
I guess it's not so surprising.
The DA* was designed for APS-C. The old f/1.2 had to cover 24x36mm.
The size of the front glass seem to suggest otherwise, at least at first sight... which makes me think that is more a problem of mechanical vignetting (barrel design), rather than an exclusive function of the optical design.

It seems that forum users have different opinions on this subjects, and that some prefer to see pictures with a higher iconographic value, not dumb test pics.
Though I still believe that a well chosen test subject can highlight important characteristics of the different optics, and guide the perspective buyer to a more informed purchase.
It is also good food for thought for those, like me, who are interested in vintage optics, and see them not only as collector's items, but also as usable picture taking tools.
The critical examination of well though test pictures con provide a lot of information that would likely be hidden in "beautiful" photos that are not meant to highlight the "optical signature" of the lens.

Ignore the nay sayers! What matters is that some people do find test images both interesting and valuable.

Ultimately, the only way to create images with the highest possible iconographic value is to master the tools of photography. And that means learning how different lenses handle different scenes. Careful test images are a great way to learn about lens behavior. In contrast, higher iconographic value images actually make poor test images -- is the look of the image due to the lens, the lighting, the scene, or the post processing?

[Breakfastographer]

[...] The size of the front glass seem to suggest otherwise, at least at first sight... which makes me think that is more a problem of mechanical vignetting (barrel design), rather than an exclusive function of the optical design. [...]

It seems to me that in the olden days, it was mostly assumed that the front element should be the determinant of maximum aperture. I believe it's only been in the last 15 years or so that manufacturers baffeled down the capabilities of the front lens to give a sharper image. My impression could be wrong - and even if mostly true, somebody will surely pipe up with a pioneering counter-example or two.

There are various corollaries, such satisfying pixel peepers who limit themselves to considering the merits of a lens only at the widest aperture, and not needing a 13-blade rounded aperture to give nice bokeh at the aperture where the pixel peepers might be satisfied.

I don't know if Pentax' DA 35/2.4 is an example of this, cut to size from an f/2 original. Maybe it was done for price point.

[...] It seems that forum users have different opinions on this subjects, and that some prefer to see pictures with a higher iconographic value, not dumb test pics.
Though I still believe that a well chosen test subject can highlight important characteristics of the different optics, and guide the perspective buyer to a more informed purchase.
It is also good food for thought for those, like me, who are interested in vintage optics, and see them not only as collector's items, but also as usable picture taking tools.
The critical examination of well though test pictures con provide a lot of information that would likely be hidden in "beautiful" photos that are not meant to highlight the "optical signature" of the lens.

Well, let me come out and say that I thought the test pictures were fantastic, no complaints here at all. Highly useful and appreciated.

[pinholecam]

I love to use vintage lenses. I always did, but after I bought the K-1 I'm appreciating them even more, cause I can finally use old optics on the same format they were designed for.
When I don't have the chance to photograph something more interesting, I like to play with old lenses and see if some of them have any practical worth as photographic tools, or just have some collector value.
Many times the result is just average, or worse, but there are times when I find that an old lens has a great practical value, either because it performs at the same level of a modern high quality zoom, or because its optical signature provides a kind of look that no modern lens would ever give.
I would love to find on this forum suggestions and examples posted by other members. It would help orient my purchases or make me stay away from hopeless lenses.
It would be even more useful to less experienced users who have just got involved with vintage glass.
Unfortunately most of the reviews are not very in depth nor very reliable, and often lack high definition examples of the kind of subjects that would highlight the strong points and the weaknesses of the various lenses.
I like to read well done comparative tests, but it takes time and a certain effort... so I haven't seen any of them recently, on pentaxforums.
Sample images would help, but most of the pictures posted here are shot with modern glass, and the relatively few taken using vintage lenses are either dramatically downsampled or represent subjects that (albeit nice to the eye) don't show the limits of the optic.
I'm not asking for newspapers or brick walls, just high res images of subjects that fill most of the frame and have a certain depth (to have at least some part of the image correctly in focus, in case of imprecise focusing).
I have no idea if other people would find it useful, or just plain boring. Personally I would like to see a thread dedicated to vintage lenses, with test pictures (and comments) that would help to understand what we can expect from such optics.
Recently I am shooting this kind of silly photos for myself, let's say it's a pastime to find out which of my old lenses is worth keeping in active use, and which are better kept stored as collector's items.
In the process, I'm finding that some old optics are really quite awful, while some others have impressed me beyond any expectation.
It doesn't take much: a correctly focused picture of a flower plant, or a bush, moderately post processed, and uploaded to a site that does not resize the jpg.

If any of you has done a comparative of various lenses for fun, for your own use, I encourage to post your findings.
I'm sure other users would find it interesting.
I understand a proper test would take time and a certain competence, so I'm also asking if there is any interest for a thread where commented test images of vintage lenses could be posted, with a more casual, less structured approach.

I had a running thread for about 2.5yrs (2014 to 2016).
[pinholecam] A week with ...... (random ramblings of a lens junkie) - 2015 | ClubSNAP Photography Community

I am disinclined to measurement type write-ups.
They are a pain and boring to shoot and adds nothing to my photography growth.
What I like is to just take the lenses out and shoot them over a period of time and hopefully cover various genres that I am interested in.
So over the period of shooting, I get to know the strengths, character, weakness of the lens.
It also improves me photographically to be able to use a lens to its strengths.


I gave up on the 'all sharp' vintage lens.
If one wants a MTF monster, pay the money and buy a modern one with the proven MTF figures.
Probably spend less that way than buying/trying many old lenses.

Personally, I find that I like old lenses for their character/trade-offs/flaws.

[cyberjunkie]

I gave up on the 'all sharp' vintage lens.
If one wants a MTF monster, pay the money and buy a modern one with the proven MTF figures.
Probably spend less that way than buying/trying many old lenses.

Personally, I find that I like old lenses for their character/trade-offs/flaws.

I will check that thread with curiosity. I'm always interested in this kind of subjects.

Regarding the practical photographic worth of "sharp" vintage lenses, I substantially agree with you.
Many of them are not as sharp as modern ones, and have nothing special to offer.
Though I haven't sold a single one... cause I love collecting them. Which in practice means that I have a problem parting with items that I didn't acquire by chance, or just because they were cheap.
Almost all of them were chosen for a reason: expected performance, historical relevance, mechanical construction, aesthetics, interesting optical flaws, identity/period/nation of the designer/maker.
A good number of them have a very special value to me. I studied the available info, tracked them down, and tried to ponder about the price and the state of conservation... there was a process before buying them.

Having said all that, it is true that the vast majority of vintage lenses worth acquiring make practical photographic sense because of their "character". Which in practice is the expression of their optical shortcomings.
Though I wouldn't generalise and make it a rule.
In the first place, there are objectives that work so well in manual focus, and have such a great build, that this reason alone could justify their use in specific situations or fields of use (like high magnification macro), in place of modern AF objectives.
Even if we forget about ease of use and the intrinsic pleasure of using well built, well designed photographic tools, there are a minority of vintage lenses that can actually compete with present time offerings in price/performance ratio.
Just think of a Leitax'ed Summicron 2/50mm. Even today, it can be considered a very sharp lens, with even performance across the field.
I personally found that a small number of old zooms are still competitive too.
The Vivitar Series 1 Flat Field 90-180mm has a very old design, but still gives a lot, even considering its not-so-cheap average price: 1:2 macro across the zoom range, and very good sharpness at close range and medium apertures. I don't see many modern alternatives...
There are not so many vintage zooms that are still competitive, but they do exist.

A few selected objectives still have a lot to give, especially considering their PRICE.
Similar (or better) modern lenses are expensive.
If we don't ask very good sharpness wide open, there are affordable vintage lenses (including a few zooms) that give an optical performance comparable with modern designs, at a fraction of the price.
Though in general I can say that I personally agree with you.
The real value of most desirable vintage lenses is due to their peculiar "optical signature", which in turn comes from optical flaws (aberrations).
Their "funny" rendering is the main reason for buying one.
Very few modern lenses can give the same kind of images, and usually have crazy expensive price tags (see Leica or present time Meyer).


EDIT:
Your shots with the little Pentax-M 20mm are a very nice example of what you can achieve with a good vintage prime that is not on par with modern offerings, especially wide open, but has other very important advantages (read: weight and bulk).

[Lowell Goudge]

I guess that explains why I was unable to find a few existing threads on the index. Thanks for the information and for your volunteer effort in maintaining this resource.


Steve

Take a look at the index , it is cleaned up, and I think Adam tidied up the links

[jcdoss]

Every Pentax image on my website was taken with a "vintage" lens, mostly M and K, and a few new A additions. Skill notwithstanding, I don't find much to complain about except the occasional fringing issues, which nowadays is largely correctable even in Lightroom. Feel free to view and ridicule as long as you wish.