[subidoc]

I already have a Takumar Bayonet (not SMC) 135/2.5 and I am getting used to it... I still need to explore it some, but any deficiencies I have noted are likely related to my skill than the lens, I'd like to think. Color though seems a little blah, but I may need to tweak the settings a bit.

However, I also am seeming some SMC 100/f4 Macro in the thread-mounts out there, and I know the 100/2.8 is supposed to be brilliant. Here is my dilemma:
1. Should I get the 100/f4 as well, and see which one I like better (100 v/s 135), and likely get rid of the 135 later? Is the 100/4.0 a better long-term investment from a collection point of view, as well as pleasure of use?
2. Should I wait for an affordable (whaterver that means) 100/f2.8? I can't seem to be able to find it less than $180-200.

I use a *ist DS. I would like to begin to grow a collection of fast primes that I might use professionally (part time) for portraits, etc. I am not really into bugs, insects etc, so the macro does not really interest me.

I have a 28/2.8 SMC, 50/1.7 SMC, Tamron 28-75/2.8 XR Di, 18-55 DA AL II, Spiratone Pluracoat 70-105 with macro (that I am going to get rid of), and the Takumar Bayonet 135/2.5 (single coated) in K-mount. I have an M42 adapter, but no lens at this time.

Also, what is a Preset lens? I saw a 105/2.8 preset, but don't know anything about it.

Seeking some words of wisdom from the wise and expereinced.... Thanks in advance.

[Mechan1k]

I'd say a 100/4 Macro Tak will be a very sharp lens indeed.

I can't comment on the 135/2.5 .... but i can comment on the 135/3.5 as it is a very nice lens ... nice colours and contrast ... and sharp with nice bokeh as well.

If you can ... definitely try and get a 100/2.8 lens though ... it's a nice little lens.

[reeftool]

The 100/4 is a macro which makes it worth owning both.

[Just1MoreDave]

On a DSLR, 135mm lenses are a little too long for portrait, in my opinion. They are great if you want to take a portrait from the next room. I am more comfortable using something from 50-105mm. Within that range, you'll find a lot of macro lenses. The macro lenses can double as portrait lenses too. They are bulkier, possibly slower focusing and more expensive, but they work fine. I might eliminate the SMC Pentax-M 100mm f4 macro (or the identical 100mm f4 Takumar, K and A versions) because the f2.8 lenses will have a brighter viewfinder and the option of a narrower depth of field.

That leaves a lot of lenses. You already have a 50mm so skip that for now. There are some 55mm options that I like but they're close enough to 50mm to skip also. Here are some inexpensive suggestions:

SMC Pentax-M 100mm f2.8 - There's a Pentax-A version that's nearly the same, works better with your camera, has an integral hood, but is harder to find and more expensive. Takumar 105mm f2.8 lenses have similar performance. A Super-Takumar 105mm f2.8 might be $70, a Pentax-M $100, Pentax-A $200.
Tamron Adaptall-2 90mm f2.5 - You'll need an Adaptall to K-mount adapter. The lens itself is common and you can sometimes find them for under $100. The adapter is $20 for the basic model, $80-100 for the KA mount version.

You can get a couple of 85mm lenses for less than $300:
Super-Takumar 85mm f1.9 - Built for portraits, a convenient size, and works great, but demand pushes up the price.
Bower/Samyang/Rokinon/Vivitar 85mm f1.4 - A new lens with manual focus and KA mount. It's sold under several different names and prices.

Beyond that price level, you can get more expensive versions of those lenses or some new lenses with AF. Many of these will be macro lenses, like the Sigma 70mm, Tamron 90mm, Pentax 100mm and Sigma 105mm. There's also the Pentax-DA 70mm f2.4, Pentax-FA 77mm f1.8, new Sigma 85mm f1.4, and some expensive manual focus options.

[Just1MoreDave]

Also, what is a Preset lens? I saw a 105/2.8 preset, but don't know anything about it.

It's one step in the evolution of Aperture Control. It's very convenient to focus with the aperture fully open, but we also want a range of apertures to shoot images. Here's a post describing how the preset lenses work:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/55603-pentax-p...tml#post540121

They're typically older M42 lenses, maybe 1950s. There are also lenses with cocking levers, like the Auto-Takumar series. Later Takumars have Auto-Manual switches.

The actual technology matters more when these lenses are used on the M42 cameras they were designed for. On a DSLR, the camera can't interact with the lens like an older camera, so you need to figure out methods to get the aperture open for focusing and closed for shooting. As long as that's possible, it doesn't matter much how it's done.

[subidoc]

The 100/4 is a macro which makes it worth owning both.

I think that puts a different argument for owning both. I'll admit that I did not think about that. Maybe because I haven't ventured into the world of macro-photography....

I'd say a 100/4 Macro Tak will be a very sharp lens indeed.

I can't comment on the 135/2.5 .... but i can comment on the 135/3.5 as it is a very nice lens ... nice colours and contrast ... and sharp with nice bokeh as well.

If you can ... definitely try and get a 100/2.8 lens though ... it's a nice little lens.

I'd love to get the 100/2.8. But the prices are just too high... As for the 135s, I hear better reviews of the SMC 3.5 version than my 2.5 single coated version. But that makes me more determined to seek out the highlights of this lens, and just have fun with it.

[Lowell Goudge]

In my K mount collection, I have SMC 135F2.5, 105mmF2.8 and 100mmF4 macro

In my M42 collection I have several 135mm lenses (F2.8 tele lentar and F3.5 SMC Tak) but nothing at all until 85mmF1.9.

I am missing the 105mm tak, or equivelent, and it is a useful FL for indoor head and shoulder portraits, where you don;t want to be in the face of the subject. the 105 mm is still on my list of lenses to get for M42 to make my collection complete.

The 135 is a great outdoor portrait and medium tele lens.

My 100mm F4 (K mount) is a macro lens, and very useful, but I will use the 105 over the macro except for close work due to extra speed.

[Marc Sabatella]

I'd love to get the 100/2.8. But the prices are just too high

Which 100/2.8 are you looking at? There are several in K-mount - the M100/2.8, the A100/2.8, and A, F, FA, D-FA, and D-FA WR versions of a 100/2.8 Macro. Of these, the "M" is the cheapest, and you should find it for closer to $100 than $200, and maybe even a little under $100 if you're patient. If nothing else, as I recall the regular price at KEH is around $130 in BGN condition, and they probably have this lens in maybe 25% of the time.

[subidoc]

On a DSLR, 135mm lenses are a little too long for portrait, in my opinion. They are great if you want to take a portrait from the next room. I am more comfortable using something from 50-105mm. Within that range, you'll find a lot of macro lenses. The macro lenses can double as portrait lenses too. They are bulkier, possibly slower focusing and more expensive, but they work fine. I might eliminate the SMC Pentax-M 100mm f4 macro (or the identical 100mm f4 Takumar, K and A versions) because the f2.8 lenses will have a brighter viewfinder and the option of a narrower depth of field.

That leaves a lot of lenses. You already have a 50mm so skip that for now. There are some 55mm options that I like but they're close enough to 50mm to skip also. Here are some inexpensive suggestions:

SMC Pentax-M 100mm f2.8 - There's a Pentax-A version that's nearly the same, works better with your camera, has an integral hood, but is harder to find and more expensive. Takumar 105mm f2.8 lenses have similar performance. A Super-Takumar 105mm f2.8 might be $70, a Pentax-M $100, Pentax-A $200.
Tamron Adaptall-2 90mm f2.5 - You'll need an Adaptall to K-mount adapter. The lens itself is common and you can sometimes find them for under $100. The adapter is $20 for the basic model, $80-100 for the KA mount version.

You can get a couple of 85mm lenses for less than $300:
Super-Takumar 85mm f1.9 - Built for portraits, a convenient size, and works great, but demand pushes up the price.
Bower/Samyang/Rokinon/Vivitar 85mm f1.4 - A new lens with manual focus and KA mount. It's sold under several different names and prices.

Beyond that price level, you can get more expensive versions of those lenses or some new lenses with AF. Many of these will be macro lenses, like the Sigma 70mm, Tamron 90mm, Pentax 100mm and Sigma 105mm. There's also the Pentax-DA 70mm f2.4, Pentax-FA 77mm f1.8, new Sigma 85mm f1.4, and some expensive manual focus options.

I can't say I have found a 105/2.8 in a K or M SMC-lens (did not know it came available like that). I thought it was always an M42 mount. Also, just looking at the numbers ($$), I would probably look at the following order of prices: 105/2.8 (as M or A), followed by the 85/1.4 (Bower/Samyang/Rokinon/Vivitar), and then Pentax/Super-Tax 85/1.4. I know the FA-77/1.8 is a beauty, but maybe one day...

I think I should just wait and watch. I'll play with the 135/2.5 until I find an 85/1.4 in great condition. Just how good are the Bower/Samyang/Rokinon/Vivitar versions? Reviews seem equivocal, but I can't say I have seen something comparing them to the 100/2.8 (which is certainly what I'd like to have).

[Marc Sabatella]

The K-mount 105 is a "K" (ie, SMC Pentax, no additional letter), not an M or A. The M & A lenses are 100's. See his sit for reasonably complete & accurate info on Pentax K-mount lenses:

Pentax K-Mount Lenses and Lens Accessories

[subidoc]

Which 100/2.8 are you looking at? There are several in K-mount - the M100/2.8, the A100/2.8, and A, F, FA, D-FA, and D-FA WR versions of a 100/2.8 Macro. Of these, the "M" is the cheapest, and you should find it for closer to $100 than $200, and maybe even a little under $100 if you're patient. If nothing else, as I recall the regular price at KEH is around $130 in BGN condition, and they probably have this lens in maybe 25% of the time.

Its is my understanding that the 100/2.8 is excellent. But is there a difference in performance based on the families you have mentioned (M, A, F, FA, D-FA and D-FA WR)? I don't think I need the D categories (certainly not the WR), but I should look at the others more closely.

[Lowell Goudge]

I can't say I have found a 105/2.8 in a K or M SMC-lens (did not know it came available like that). I thought it was always an M42 mount. Also, just looking at the numbers ($$), I would probably look at the following order of prices: 105/2.8 (as M or A), followed by the 85/1.4 (Bower/Samyang/Rokinon/Vivitar), and then Pentax/Super-Tax 85/1.4. I know the FA-77/1.8 is a beauty, but maybe one day...

I think I should just wait and watch. I'll play with the 135/2.5 until I find an 85/1.4 in great condition. Just how good are the Bower/Samyang/Rokinon/Vivitar versions? Reviews seem equivocal, but I can't say I have seen something comparing them to the 100/2.8 (which is certainly what I'd like to have).

Note as marc has commented
K mount ~100mm lenses are SMC Pentax 105F2.8 and SMC pentax 100mm F4 macro
there is a SMC-M 100mm F2.8. as well as an SMC100mmF4 macro

In M42, there is a 105mmF2.8 in various versions (tak, super tak, smc tak etc) and I believe also, but never seen one, a 100mmF2. In addition as you already mentioned the 100mmF4 macro

IN M42 lenses from pentax there are various 85mm F1.8 and F1.9 lenses but no F1.4. An F1.4 lens did not appear from pentax until th eSMC-A 84mm F1.4 with internal focusing.

[Just1MoreDave]

I can't say I have found a 105/2.8 in a K or M SMC-lens (did not know it came available like that). I thought it was always an M42 mount.

It's not very common, and priced a little high. The K-mount version is the same optically as the Super-Multi-Coated Takumar version. At some point the older versions (Super-Takumar or older) are optically different. Some people rate it as better than the Pentax-M or A 100mm f2.8. I think this is a pretty small difference.

[subidoc]

The K-mount 105 is a "K" (ie, SMC Pentax, no additional letter), not an M or A. The M & A lenses are 100's. See his sit for reasonably complete & accurate info on Pentax K-mount lenses:

Pentax K-Mount Lenses and Lens Accessories

That is a very useful site. Thank you! It helps for keeping my thoughts in order. Now I understand why the 135 (almost any) in the SMC group could perform better than the non-SMC Tak 135/2.5 I have. I will refer to this site before bidding from now on....

BTW, any one have any thoughts on the PERFORMANCE of the 105/2.5 Preset?

[pacerr]

Consider the Tamron Adaptall 90/2.5 macro lens. With a PK adapter it will essentially be an SMC-M or -K lens in use and will offer excellent results and versatility. Add the Tamron Adaptall 1.4x TC and you also have the equivalent of a 180/3.5 lens with macro potential. About $120-140 used with the PK adapter.

Adaptall-2.com

and specifically,

Tamron SP Adaptall-2 90mm F/2.5 Model 52B

I have the Super Tak 105/2.8 (M42) which is a pleasure to use also.

H2