[aslyfox]

My experience exactly, both my 24/2 and 28/2 are sticky

---------- Post added 02-03-19 at 08:40 AM ----------



I'm sure it is a common issue, but I have about 50 vintage lenses, and of these one super tak 135/3.5 and my two newer kiron 24/2 and 28/2 are the only ones with sticky blades. When you consider the population I have the kiron seem much more prone to the issue

Mine has had no problems

[TwoUptons]

I took a lot of photos with my 18-135 but I think I can make better with a f28f2.8, K30, A28f2 or k28f3.5 shooting in hyperfocal (I think it is not possible or very hard to focus manually while driving at the same time)

There is a proper order for these things: aviate, navigate, communicate, picture take...

Don’t drop the paramotor to fly the Pentax

-Eric

[monochrome]

My experience exactly, both my 24/2 and 28/2 are sticky

---------- Post added 02-03-19 at 08:40 AM ----------



I'm sure it is a common issue, but I have about 50 vintage lenses, and of these one super tak 135/3.5 and my two newer kiron 24/2 and 28/2 are the only ones with sticky blades. When you consider the population I have the kiron seem much more prone to the issue

I’ve had a Kiron / Vivitar 28/2 that arrived with sticky blades.

[pres589]

I’ve had 15 different 28mm lenses.

This is my kind of party.

---------- Post added 02-03-19 at 10:36 AM ----------

... I took a lot of photos with my 18-135 but I think I can make better with a f28f2.8, K30, A28f2 or k28f3.5 shooting in hyperfocal (I think it is not possible or very hard to focus manually while driving at the same time)...

I don't know what's going on with the mention of 'driving' so I'll leave that alone. If you're shooting hyperfocal, stopped down to f8 or f11, you will have a very hard time improving upon your 18-135. If someone had one of the above lenses and the 18-135 and wanted to demonstrate ala Wild Mark's excellent comparison shots, I think you'd find that the 18-135 may be the best performer here at circa 28mm and stopped down to f8.

[chapolin]

I don't know what's going on with the mention of 'driving' so I'll leave that alone.

I have the gaze command in my right hand, so I can take the camera in my left hand and shoot with only one finger with my right hand. So with the auto-focus it work with the 18-135. If not, need to shoot in hyper-focale. At the same time if the 18-135 is better in the sky I will use my new lens in other conditions on the floor. But have a comparison between the 18-135 and other lens that we talked about here is also a very good question. Even if I think that the 18-135 is a middle good lens who have some limits especially with vignetting ...

[JVi]

The K28/3.5 saturates very well and generally better than most other lenses. The purplish cast is a classic Pentax signature. Many of Pentax lenses give this purplish cast - it is just a Pentax thing. You can dial down the amount of this in two ways - in camera modifications to the jpg settings or post processing.

Regarding the K30/2.8 - a task for tomorrow afternoon. Just got back from an outing and now settling in for the evening

I heard a documentary on the radio less than a year ago concerning human color perception. Remarkably, certain populations in eastern Europe were found to have insensivity to dark blues and purples (short wavelength end of the visible spectrum). This was discovered in relation to noticing that this group of people had no word that describes the color blue/purple in their language. As it turned out, none of these folks could see color in that range, thus the sky was just the sky and never described to have a color.
Frankly, the deep purplish cast described as a "Pentax" signature is mostly absent in my vision. I do see the sky as blue, though, but not harsh purples in the images described for certain Pentax lens images. That is what I call an innate corrective feature for purple or violet.

A link to the story can be found here:
https://www.businessinsider.com/what-is-blue-and-how-do-we-see-color-2015-2

[Wild Mark]

I heard a documentary on the radio less than a year ago concerning human color perception. Remarkably, certain populations in eastern Europe were found to have insensivity to dark blues and purples (short wavelength end of the visible spectrum). This was discovered in relation to noticing that this group of people had no word that describes the color blue/purple in their language. As it turned out, none of these folks could see color in that range, thus the sky was just the sky and never described to have a color.
Frankly, the deep pruplish cast described as a "Pentax" signature is mostly absent in my vision. I do see the sky as blue, though, but not harsh purples in the images described for certain Pentax lens images. That is what I call an innate corrective feature for purple or violet.

A link to the story can be found here:
What is blue and how do we see color? - Business Insider

Vision and perception is definitely a variable thing. My job (career) centres on my ability to see things very well (one of my roles is to find things like a needle in a haystack). In performing this role I note variance in my colleagues aptitude (we call it observer bias). It is amazing the kinds of arguments that arise from this bias (I put these differences down to two things: inherent vision ability and learned/ cognitive processing of this input). Colour is simply a component of vision and we know this aspect of vision varies across the human race (e.g. colour blindness). In fact one of my colleagues is partially colour blind and when asked to find a certain orchid (red and green in colour), the person told me that he used differences in tone to find it (amazing skill / adaptation).

The purplish cast could be more evident because the other lenses exposed a little better (here I am trying to say that the f2 lenses seemed to grab the scene a little better from a light perspective). If I used some exposure compensation then I might get equivalence between the K28/3.5 and other lenses. This might lessen the purplish cast. Hmmm, food for thought.

[niceshot]

I’ve had a Kiron / Vivitar 28/2 that arrived with sticky blades.

do you know ,it is not a big deal. You remove the back lens group , clean them with zippo light fluid and you in action in less than 30 minutes.Be honest they are great Lens Especially the 24mm kiron.

[monochrome]

The purplish cast could be more evident because the other lenses exposed a little better (here I am trying to say that the f2 lenses seemed to grab the scene a little better from a light perspective). If I used some exposure compensation then I might get equivalence between the K28/3.5 and other lenses. This might lessen the purplish cast. Hmmm, food for thought.

I think you are describing a perception effect of the SMC coating which is no longer evident now that HD coating is the standard. In my experience the Takumar lenses, especially the S-M-C Takumars had a warm cast (decidedly not purplish or bluish. OTOH the coatings applied to the M and A lenses had a distinct and perceptible cooler cast that one could call a bluish tint. I found this especially noticeable on the M and A 50/1.4. I don't see it on every lens, particularly not the 35's which seem to render reds better than many Pentax lenses on the Macros which reder quite neutral (whar I see is what I get). I definitely don't think the K28/3.5 renders blue or purple - it is IMO warm rather than cool.

[nocturnal]

I have the K28 f3.5 and the Vivitar (Komine 28xxxx) 28mm F2.0 MC Close Focus Wide Angle in K mount

Vivitar (Komine 28xxxx) 28mm F2.0 MC Close Focus Wide Angle Lens Reviews - Vivitar Lenses - Pentax Lens Review Database

The K28/35 is a great landscape lens with little distortion.

The Vivitar 28/2 I consider is a great close up lens, it is a great 'flower' lens that produces a unique 'paint daubs' bokeh with results that look like artist paintings. I don't like it for landscapes as it suffers from lens flare, is not great at infinity and has a green/blue colour cast. But for up close flowers and leaves etc. it is a specialist being very sharp wide open at f2 with the wonderful background bokeh.

Since buying the HD DA 20-40 Limited I barely use both as I usually do landscapes and don't have to change lenses so often, plus the 20-40 is brilliant!

[Jonathan Mac]

My experience exactly, both my 24/2 and 28/2 are sticky

---------- Post added 02-03-19 at 08:40 AM ----------



I'm sure it is a common issue, but I have about 50 vintage lenses, and of these one super tak 135/3.5 and my two newer kiron 24/2 and 28/2 are the only ones with sticky blades. When you consider the population I have the kiron seem much more prone to the issue

I must be lucky - I have both the Kiron and Komine versions of the Vivitar 28mm f/2 and neither has sticky aperture blades.

[chapolin]

At the end I choose to buy a Smc k30 for 217€. I will have it in one week from Japan and we will see for the custom tax. Maybe nothing with luck and maybe around 70€ in more ...
It was so so hard to choose and I strongly hesitate with the k28f3.5 and the F28f2.8. But I really want to try the K30 and I think it will be possible to sell it without loose too much money to try the k28f3.5 or the F28f2.8.
I think the best choose was to found the A28f2 but it is rare and the only one I seen was at 400€ ...

I will post some photo here when I will receive the k30.
Thank you very very much again for your help.

[monochrome]

You made a good decision.

[BryantCP]

Hello


I use a Pentax K-5 with an Smc 18-35 and I want now a better lens but for not a lot of money. That is why I want an old manual lens. Manuel is not important for me.

I read everywhere that the Smc pentax-k 28mm f3.5 is a very very good lens but it is a little much money for me. So I founded information's on the Kiron 28mm f2 and I have the temptation to buy it also because it is a f2, more sharp I imagine ?

If the Smc is very much better than the Kiron, I will do an effort to buy the Smc, but if the Kiron is not so far of the Smc, for the pric I will preffer the Kiron.

Please can you give me an advice about this question for help ?

Thank you very much in advance !

I don't have any experience with the Kiron 28mm f2,0, but I do have their 24mm f2.0 in Nikon mount. With film, it was probably my favorite lens. Using it mostly with slide film it seemed sharp & rendered nicely. A few years ago, I bought a nice used Nikon D700 so I could use it & my other F mount lens. On the D700 it doesn't seem as sharp or contrasty as it seem on my film Nikons, probably due to inferior lens coatings not optimized for digital sensors (compared to Pentax's SMC coatings). The Kirons are nicely made lens, I wish they were still in business.

[pres589]

My Kiron 28 f2 is wonderful for low-light photograhy on my K-5. A hood helps with some of the softness and lack of contrast in daylight. I really like it on film as well.