[gump]

After a year with a K-70 I am comfortable enough to look at additional lenses. At this time it is improve upon the 18-55 kit lens for "portrait" shots. I am not professional and do not do a lot in this area so that makes me hesitate to invest big bucks. The Pentax 50mm seems a logical choice. It get high marks in PF reviews. There seems to be good selection in the used market. Where I have been stopped is that there are apparently 3 varieties, full AF and aperture control, MF with "A" setting, and the "M" which recalls the good old days. Yes, one is faster than another, aren't we all. The usual stuff I shoot does not demand any of these particular features.

The question. Are there any aspects, quirks, or problems in any variety of the lens that are missing from the reviews?

[aslyfox]

" there is an " article (s) " for that "

at least part of that:

Pentax 50mm Prime Lens Shootout
Introduction
Pentax DA 50mm F1.8 vs FA 50mm F.14 vs FA 50mm F2.8 Macro

What’s so nifty about a fifty millimeter lens? Recently digital camera makers have begun to release 50mm lenses, Canon, Nikon and now Pentax have all released a new prime 50mm lens. There are number of reason why this renewed interest in what was consider a “normal lens” for 35mm but for most digital cameras is a short telephoto. First, 50mm lenses are usually at least two stops faster than most reasonably priced zoom lenses on the market. Second, the 50mm focal length has long been used on 35mm cameras for decades and enjoys some of the best utilized and corrected optical designs. Generally 50mm lenses are often the sharpest optics in the manufacturer's line. Third, most 50mm are very reasonable priced and are a great entry point to obtain a prime lens. Because of the APS-C sensor size a 50mm lens has a field of view of a short tele - it corresponds to a 75mm lens on a 24 x 36 mm (aka full-frame) camera.

Currently Pentax makes three different 50mm lenses: the SMC Pentax FA 50mm F1.4, D FA 50mm F2.8 Macro, and DA 50mm F1.8. All three can be used on digital cameras and the first two are considered full-frame lenses. Although the DA 50mm is marketed as an APS-C-only lens, some speculate that it may also work on full-frame (i.e. film) cameras. There is thread concerning this issue on our forum, but until the issue is finally put to rest we will have to take the position that the lens is to be used only on APS-C digital cameras and is not full-frame compatible.

Read more at: Pentax 50mm Prime Lens Shootout Review - Introduction | PentaxForums.com Reviews

and then there is also the star 55mm F1.4 that some might consider as well:

Pentax-DA* 55mm F1.4 Review
Introduction
Pentax DA*55mm

Does having a star in your name really make you a brilliant choice? Recently we completed a comparative review of the Pentax 50mm lenses that are currently being produced titled, Pentax 50mm Prime Lens Shootout. We intentionally did not include the Pentax DA* 55mm F1.4 lens in the comparison for a number of reasons, as we found it to be a vastly different lens with an entirely different target audience than the other three lenses. Apart from having a slightly longer focal length, the DA* 55mm employs the KAF3-mount, which means that the autofocus is very quiet, but also that it won't autofocus on cameras older than the K10D. Its price tag is two to three times as high as that of the DA 50mm F1.8 (the winner of the 50mm shootout), but it is fully weather-sealed, adding a great deal of versatility.

Read more at: Pentax-DA* 55mm F1.4 Review - Introduction | PentaxForums.com Reviews

[pschlute]

After a year with a K-70 I am comfortable enough to look at additional lenses. At this time it is improve upon the 18-55 kit lens for "portrait" shots. I am not professional and do not do a lot in this area so that makes me hesitate to invest big bucks. The Pentax 50mm seems a logical choice. It get high marks in PF reviews. There seems to be good selection in the used market. Where I have been stopped is that there are apparently 3 varieties, full AF and aperture control, MF with "A" setting, and the "M" which recalls the good old days. Yes, one is faster than another, aren't we all. The usual stuff I shoot does not demand any of these particular features.

The question. Are there any aspects, quirks, or problems in any variety of the lens that are missing from the reviews?

If you go for an older A or M series you really should get a hood for it. This is good advice whatever you shoot with to be honest.

If you go for a M or A lens make sure your subject is good at staying still while you focus !!

The older lenses are also a bit problematic when using P=TTL flash. If you later branch out into using flash either on or off the camera you will have more options with a AF lens. Have a look for a second hand FA 50mm 1.4 or 1.7. Great performers and very reasonable.

[PJ1]

I have a few 50mm lenses (Super Takumar (50/1.4 and 55/1.8), M 1.7, FA 1.4 plus a Zeiss Tessar 2.8 (just for nostalgia)). They are all very good when used with their limitations in mind - mainly in the coatings. The older single-coated lenses will not be as flare resistant as the newer coatings. But that's about it for my money. If I wanted a 50 I could use any of them quite happily. The cheapest is probably the Super Takumar 55/1.8 and it is a very nice lens.

[bdery]

I suggest you read this in-depth review, it should be helpful for you:

Pentax 50mm F1.4 comparison: M, FA and DFA Review - Introduction | PentaxForums.com Reviews

[Gary H Perth]

My first thought is that any one would be good. I have several 50mm lenses, one each of all the types you list, all give good results on my K-70:
M 50mm/f1.4 is brightest in viewfinder so easy to focus, but wide open the depth of field is so narrow that it is hard sometimes to focus handheld. Mine is in great condition, rotates smoothly and the green button always gives me spot-on exposure (I usually shoot at f4-f8). You are a bit more limited in what features you can use with an M series lens on Manual setting with the green button.
A50mm/f1.7 gives me many great photos and the A setting allows the thumbwheel aperture adjustment. This was ridiculously cheap, optically perfect but has a slightly graunchy aperture ring - so I leave it on the A setting. Manual focus is easy with the f1.7 max aperture.
FA 50mm/f1.4 - autofocus solves the issue above of needing a good eye to get the focus precise as with the M. It looks a bit dated and plain but is a great lens to use and the autofocus is always good and quick.

in summary, I am reinforcing the reviews as being directly applicable in my case. I love the ergonomics of the M series way above the other two, but that is not about the image. Anything below $100 that you can test on your K70 would be satisfactory - the individual lens is a more critical choice than which lens series. Your K70 has a good screen where you can zoom your test shots before buying. I have a 49mm shade for outside use, as the older coatings are not as good as the later ones

I have an even older K-series 55mm/f1.8 and that is superb, but a bit of a cult classic and may be priced accordingly. The best of all my lenses in the hand.


Of course you could watch out for a 50mm macro which is more versatile but a slower max aperture and therefore a greater depth of field wide open. Mine is a Sigma EX 50mm/f2.8 macro and it makes a terrific portrait lens as well as a very sharp macro, but is usually closer to $200.

[Pentax Syntax]

Well the reviews of the many 50s are pretty complete so I am sure most of the quirks are in there somewhere. I own 6 50mm lenses and have used and sold many more. Here is my take:

The manual focus on the M and A series is so wonderfully damped and responsive that I much prefer them to the F and FA series.

The 50 macros are versatile but somewhat slower (2.8)

The large aperture 50s can produce dreamy images hard to reproduce in PP.
My favorite is the A 50 1.2.

As others have stated get a good hood.

The FA 1.4 (or1.7) are good overall choices.

Hope you enjoy your 50!

[Bertrand3000]

If you are budget limited, consider the DA 50 F1.8. It's the cheapest lens available new, and it will give you good IQ and AF.
If you don't care about AF, you have many choices, the most popular are A50 F1.7 and M50 F1.4.
Avoid A50 F2, it's quality is inferior.

Keep in mind that a 50mm lens on an APS-C body (e.g., K-70) gives you a narrower angle of view than it would on a 35mm film camera (or full-frame dslr). If you want the "normal" prime lens for an APS-C camera, you want something like a 31mm or 35mm. The focal length designation for a lens doesn't change depending on sensor size, but the viewing angle does.

Take a look at this range of lenses:
Prime Lenses between 31mm and 55mm | PentaxForums.com

I, myself, use the DA* 55mm but I don't do portraiture much, and mostly shoot outdoors, so I use a zoom for wider angles on the APS-C, and only use WR or AW lenses. As already noted, the 50mm f/1.8 is a terrific value, a great lens for a very reasonable price.

[gump]

Keep in mind that a 50mm lens on an APS-C body (e.g., K-70) gives you a narrower angle of view than it would on a 35mm film camera (or full-frame dslr). If you want the "normal" prime lens for an APS-C camera, you want something like a 31mm or 35mm. The focal length designation for a lens doesn't change depending on sensor size, but the viewing angle does.

Yes, I understand angle or field of view. I think my interests give me the flexibility to consider the Pentax 35, 40, 50. Third party lenses, or going outside the 35-50 range, is always possible. My kit lens does a descent job at 35mm but was looking to get better IQ at the upper end. My 55-300 does well at its lower end. I don't do people portraits but would if asked. I doubt if this would be heavily used so it dictates $$, but I have encountered particular objects that deserve a quality image which a prime would do. Who knows I might be right?

[HYS]

I used to work with SMC macro 50/2.8 for some time and still regret selling it. Fantastic lens for me...

[aslyfox]

as I often do, I recommend considering renting equipment before making a purchase

Information on Businesses that offer cameras and lenses for rent - Page 2 - PentaxForums.com

got an email from LensRental discount on rentals arriving by Oct 25 - PentaxForums.com

do your own testing

[stevebrot]

The question. Are there any aspects, quirks, or problems in any variety of the lens that are missing from the reviews?

The reviews are pretty complete and while it is pretty hard to draw generalizations beyond the obvious, allow me to give it a try...

• Almost all Pentax 50mm and 55mm lenses offer above average or excellent optical performance
• The exceptions to the point above would be the Pentax-M 50/2.0 and Pentax-A 50/2.0; both are average at best and are poor value
• The DA 50/1.8 is probably the best value in a 50mm lens for your camera in that it will work seamlessly in all exposure modes (including flash), does auto focus, and is very competent, optically. Manual focus is a pleasure, too. The trade-off is that it has no aperture ring or focus scale.
• All Pentax 50mm f/1.7 share optical design and are excellent performers and are arguably "better" at all shared apertures than their f/1.4 and f/1.2 counterparts. The same is true of the Pentax-K 55mm f/1.8 and f/2.0.
• The Pentax-K and Pentax-M 50mm f/1.4 share optical design while later versions offer a refinement of that design. Both have their fans.
• Getting f/1.4 or f/1.2 will buy narrower depth of field, greater weight, more aperture blades*, and a 2/3 or 1 stop low light advantage over an f/1.7 lens
• The best combination of build and feel will be found on Pentax-K, M, and metal-build A series lenses. The trade-off is that lack of auto-focus.
• Despite excellent optical performance, there is a general caution regarding the Pentax-A 50/1.7. A side effect of its plastic construction is a general weakness in its aperture ring construction such that most (all) will jam and fail if they have not already. This is not a huge issue if one can leave the ring in the "A" position and never use the lens with extension rings or bellows for macro or with most adapters on Canon or mirrorless cameras. If one wants the "A" contacts and great build quality, the Pentax-A 50/1.4 might be the better purchase.

I hope this helps.


Steve

* A higher aperture blade count is supposed to result in more pleasing background blur (bokeh). Some also feel that a six-blade highlight outline is ugly compared to that from eight blades.

[stevebrot]

I forgot to mention, that while 50mm is a traditional "normal", the 35mm focal length is a more versatile general purpose non-zoom for the K-70. The DA 35/2.4 is a fine little lens and great value. Even better might be the FA 35/2.0 if you find a good deal.


Steve

[aslyfox]

The reviews are pretty complete and while it is pretty hard to draw generalizations beyond the obvious, allow me to give it a try...

• Almost all Pentax 50mm and 55mm lenses offer above average or excellent optical performance
• The exceptions to the point above would be the Pentax-M 50/2.0 and Pentax-A 50/2.0; both are average at best and are poor value
• The DA 50/1.8 is probably the best value in a 50mm lens for your camera in that it will work seamlessly in all exposure modes (including flash), does auto focus, and is very competent, optically. Manual focus is a pleasure, too. The trade-off is that it has no aperture ring or focus scale.
• All Pentax 50mm f/1.7 share optical design and are excellent performers and are arguably "better" at all shared apertures than their f/1.4 and f/1.2 counterparts. The same is true of the Pentax-K 55mm f/1.8 and f/2.0.
• The Pentax-K and Pentax-M 50mm f/1.4 share optical design while later versions offer a refinement of that design. Both have their fans.
• Getting f/1.4 or f/1.2 will buy narrower depth of field, greater weight, more aperture blades*, and a 2/3 or 1 stop low light advantage over an f/1.7 lens
• The best combination of build and feel will be found on Pentax-K, M, and metal-build A series lenses. The trade-off is that lack of auto-focus.
• Despite excellent optical performance, there is a general caution regarding the Pentax-A 50/1.7. A side effect of its plastic construction is a general weakness in its aperture ring construction such that most (all) will jam and fail if they have not already. This is not a huge issue if one can leave the ring in the "A" position and never use the lens with extension rings or bellows for macro or with most adapters on Canon or mirrorless cameras. If one wants the "A" contacts and great build quality, the Pentax-A 50/1.4 might be the better purchase.

I hope this helps.


Steve

* A higher aperture blade count is supposed to result in more pleasing background blur (bokeh). Some also feel that a six-blade highlight outline is ugly compared to that from eight blades.

very detailed

I would add that there is only one star lens in the group:

Pentax-DA* 55mm F1.4 Review
Introduction
Pentax DA*55mm

Does having a star in your name really make you a brilliant choice? Recently we completed a comparative review of the Pentax 50mm lenses that are currently being produced titled, Pentax 50mm Prime Lens Shootout. We intentionally did not include the Pentax DA* 55mm F1.4 lens in the comparison for a number of reasons, as we found it to be a vastly different lens with an entirely different target audience than the other three lenses. Apart from having a slightly longer focal length, the DA* 55mm employs the KAF3-mount, which means that the autofocus is very quiet, but also that it won't autofocus on cameras older than the K10D. Its price tag is two to three times as high as that of the DA 50mm F1.8 (the winner of the 50mm shootout), but it is fully weather-sealed, adding a great deal of versatility.

Read more at: Pentax-DA* 55mm F1.4 Review - Introduction | PentaxForums.com Reviews

just in case that might be of interest