[onlineflyer]

That's a very good comparison of each lens, Wild Mark.

[Dipsoid]

Pentax-M 28mm f/2.8 (first version, with silver decorative ring) is excellent stopped down to f/11. The second version (without silver ring) is excellent at f/8.

I found the first version really poor. It may have been my copy but my 18-135 was much sharper at equivalent apertures.

[chapolin]

Thank you very much for your answers !!
It really help me and more with comparisons of the different Smc 28mm

The choice is so so hard. Maybe I will take Smc k 28mm f3.5 because it will be the safest in time to be happy. I think that if i take a Kiron it will be the A one to not have mechanical problems but the price of the bargain is same of te Smc ...
But maybe the smc F 28mm f2.8 but seem to be less under ...

On the photos of Wild Mark, the differences are at the same time not important and ... important with a long utilization ... but depend also of the photographer lol
Do the smc k 30mm f2.8 is up to its reputation and can represent an alternative to k 28 f2 ? or k28f3.5 ?


Thank you very much again.

[KC0PET]

They probably aren’t good investments at all, just great lenses.

Most of the K primes have dropped to lunch money prices the last couple years. I hectored J. Colwell years ago to get my hands on his K35/3.5 but he wouldn’t let go of it. I won’t admit what I eventually paid for the copy I use, but I recently acquired a NOS copy still in the plastic, in the case, in the box, for $99.

It takes a certain breed of cat to appreciate K primes.

Yes, good point, from a financial perspective not a good investment. Many lenses are really a bargain these days. In the late '80s and early 90's when I started having money to buy camera equipment I was paying similar or higher prices for similar lenses both new and used. The ones I have sold I feel like I have given them away. Adding inflation into the mix really camera equipment in general is a bargain these days. But from a "buy a lens that you will love and never want to get rid of" it may be a good investment. For us folks that like vintage manual prime lenses it seems that most really like the K primes.

And I will own up to being a special breed of cat

---

Last edited by KC0PET; 02-02-2019 at 09:10 AM.

[baro-nite]

Do the smc k 30mm f2.8 is up to its reputation and can represent an alternative to k 28 f2 ? or k28f3.5 ?

It's very sharp (although disappointing when reversed for macro), smaller than the other two in your list. Quite a bit more expensive than the 28/3.5, I think mainly because it relatively rare (as opposed to the K28/2, which is rare and expensive because it was a costly lens to produce in the first place). Is it worth the price premium compared to the 28/3.5? Probably not, unless the smaller size and slightly faster maximum aperture are important to you.

[Wild Mark]

Thank you so much for the comparison images.
I took a look at these in some detail and my impressions are:
1. The K 28 2 has the best bokeh wide open. The out of focus areas are smooth and not 'pixelated' in appearance.
2. The central sharpness at f11 is ~ the same across the board without disceranable differences (I have one eye that is at 15/20 still).
3. All showed chromatic aberrations (fringing) when wide open at the high contrast areas where the sea spray meets the land, however, the K 28 2 and K 28 3.5 have much less than the A a M lenses (the A seems to have the most fringing).

Spot on! The K28/2 has almost no fringing. The K28/3.5 has a little and also has a noticeable pentax 'purplish cast'. The A and M 28/2 do exhibit more fringing - definitely, the M being worse than the A. This is why I feel the M28/2 is not as good as the K28/3.5 despite its bokeh benefit wide open and is why I rate the A28/2 a notch above the K28/3.5. Of course, the K28/2 is in a class of its own (and paying the price for one is indeed necessary).

---------- Post added 03-02-19 at 08:47 AM ----------

Do the smc k 30mm f2.8 is up to its reputation and can represent an alternative to k 28 f2 ? or k28f3.5 ?

I can go back to the same spot if you like and check the result of the K30/2.8. Many say the K30/2.8 is the poor mans FA31/1.8. I feel that is a fair label too (and I have read somewhere in unsubstantiated chit chat that the K30/2.8 was the precursor to the FA31/1.8).

[chapolin]

The K28/3.5 has a little and also has a noticeable pentax 'purplish cast'

I seen very carefully all your f11 photos comparative and I see a lot the 'purplish cast K28/3.5, other users do not think it is too much ? I am affraid with that thing if i buy this lens ...

I can go back to the same spot if you like and check the result of the K30/2.8.

yes thank you very much in advance if you can do that !

[officiousbystander]

Don't forget the Ricoh Rikenon XR 28 2.8. It's usually quite cheap. But Pentax forum members know quality when they see it.Ricoh 28mm F2.8 Rikenon XR Lens Reviews - Ricoh Lenses - Pentax Lens Review Database.

[Wild Mark]

I seen very carefully all your f11 photos comparative and I see a lot the 'purplish cast K28/3.5, other users do not think it is too much ? I am affraid with that thing if i buy this lens ...






yes thank you very much in advance if you can do that !

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

[chapolin]

The K28/3.5 has a little and also has a noticeable pentax 'purplish cast'

I have looked carefully side by side all your f11 photos and I see the 'purplish cast' strongly and I do not found it with the other 28 on yours photos ... It is always like that with the K28/3.5 ? It is not a problem for the users or it is a thing that they like ?

I can go back to the same spot if you like and check the result of the K30/2.8.

Yes thank you very much in advance if you can do that and it will not take too much of your time. I really hesitate to choose the k30, even if it can be a lot of money. I need a 28mm because I will make some photo in the sky with my paramotor. I will shoot in hyper-focal (I do not know if it is the good term in English), but I think that the 30mm is not far of the 28mm in term of angle.


Ps I posted this message yesterday but I had a problem with the interface

[Wild Mark]

Yes thank you very much in advance if you can do that and it will not take too much of your time. I really hesitate to choose the k30, even if it can be a lot of money. I need a 28mm because I will make some photo in the sky with my paramotor. I will shoot in hyper-focal (I do not know if it is the good term in English), but I think that the 30mm is not far of the 28mm in term of angle.

If you are shooting night skies then you will need a faster lens and possibly wider than 28mm. You might do better with the K24mm f2.8 if funds are tight.

I have looked carefully side by side all your f11 photos and I see the 'purplish cast' strongly and I do not found it with the other 28 on yours photos ... It is always like that with the K28/3.5 ?

I have a few copies of the K28/3.5 - I can test these and see if there is a trend or if it is my personal copy.

---------- Post added 03-02-19 at 09:12 PM ----------

I need a 28mm because I will make some photo in the sky with my paramotor

Ok, not night skies, Paramotor is a flying gadget. Sounds like fun.

[Jonathan Mac]

A 28mm f/2 will be generally more useful that an f/3.5 because of the extra speed. The image quality of the K 28/3.5 is exceptional and the third-party f/2s don't have that touch of magic but they be more flexible in use.

If it's just for landscapes and you're sure you really won't need the extra speed the K is a better choice. But for general use I'd go for the f/2.

[chapolin]

If you are shooting night skies

Yes I want also to shoot at the end of the day but it will be not the priority. Last week I founded a A24mm f2.8 in Ebay for 130€ but I missed it, it had stay only 2 or 3 hours before someone buy it ...

Paramotor is a flying gadget. Sounds like fun.

I do not want also to make photos with my paramotor but generally I make a lot of photos in the sky.

Here you can see with a gopro one of my fly the last summer :

Youtu.be

Youtu.be

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)


Now I really hesitate with the k28f3.5 because it is cheaper solution but I am afraid with 'purplish cast' color. If it turned out I will prefer the other solutions more expensive ...

[chapolin]

I founded an interesting photo :


Pentax M28 vs. K30 | Same scene, uncropped, tripod mounted, ? | Flickr

[Lowell Goudge]

If you decide on the Kiron or Vivitar equivalent, be sure the aperture is clean and in good working order. Sticky blades are common.


Steve

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

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

is that true only for those lenses or is that something to be careful about with other vintage lenses ?

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