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SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM Review RSS Feed

SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM

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150 489,312 Mon January 4, 2021
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94% of reviewers $800.41 9.01
SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM

SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM
SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM

Like all current DA lenses, the SMC Pentax DA* 50-135mm is designed only for Pentax APS-C DSLR cameras. It was announced in late February, 2007. It auto-focuses with an SDM ultrasonic motor on the K10D (firmware 1.30) and newer cameras. On older cameras the lens will auto-focus with the 'screw drive' mechanism.

SMC Pentax-DA* 50-135mm F2.8 ED [IF]
©, sharable with attribution
Image Format
Lens Mount
Pentax K
Aperture Ring
Automatic, 9 blades
18 elements, 14 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
AF (in-lens motor or screwdrive)
Min. Focus
100 cm
Max. Magnification
Filter Size
67 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 31.5-11.9 ° / 27-10 °
PH-RBK 67 mm
Lens Cap
Weather Sealing
Yes (AW)
Other Features
AF/MF Switch,Internal Zoom
Diam x Length
77 x 136 mm (3 x 5.4 in.)
685 g (24.2 oz.)
w/ Hood: +80g
Production Years
2007 to present (in production)
$877 USD current price
Engraved Name
smc PENTAX-DA* 1:2.8 50-135mm ED [IF] SDM
Product Code
User reviews
In-depth review
Unofficial Full-Frame Compatibility Tests by Pentax Forums
★☆☆ Usable with reservations at select F-stop/focal length combinations
Show details
Internal zoom.
Three ED elements.

Screwdrive AutofocusSupersonic AutofocusQuick ShiftWeather SealedInternal FocusingInternal ZoomingAutomatic ApertureAPS-C Digital Only
Purchase: Buy the SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM
In-Depth Review: Read our SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM in-depth review!
Sample Photos: View Sample Photos

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Forum Member

Registered: April, 2018
Location: Tartu
Posts: 78

5 users found this helpful
Lens Review Date: December 19, 2018 I can recommend this lens: Yes | Price: $500.00 | Rating: 9 

Pros: light weight - weathersealed - sharpness - bokeh
Cons: slow AF
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 7    Handling: 10    Value: 10    New or Used: Used    Camera Used: K50 & K3 & K1   

Pentax DA*50-135 F2,8

My thoughts after 18months of use.
(not a review, I don't have the necessary know-how and equipment to review a lens.)

Ergonomics and design
  • Very good size and weight. You can definitely carry it around all day, even shoot one handed on the wider end.
  • The weathersealing is tight. It will even survive underwater for some time. (don't ask me, just know it's not completely watertight :P) In rain, no question.
  • The grips are from rubber and real tight. The rubber hasn't slipped once even after I've removed it from the zoom ring various times. (why? Keep reading)
  • The resistance on both the zoom and focusing rings are good. No complaints there.
  • The hood is long and tough. It might seem sometimes it doesn't attach properly, but in real use it has never come loose so no lost points there. I'm actually glad it's big. Makes you feel bigger and helps keep the contrast.
  • This lens has an dedicated MF/AF switch. I don't use it much at all because in addition it has quickshift: you can use manual focus in AF.
  • Mounted on a tripod (a rather cheap one ~50$) it doesn't move in landscape orientation. When I turn my ballhead 90 to the side (portrait orientation) it has a hard time keeping steady and sometimes starts sliding. So a tripod collar would have been nice with this lens :/
  • The housing is made from metal and the paint hasn't started coming off from any parts. My copy is almost 8 years old and it still looks like a mint one from the outside.

  • It's okay. The bokeh is smooth (no onion rings etc) and keeps it's round shape throughout it's apertures.
  • There is some aberration, but very minor and mostly goes unnoticed.
  • Haze is under control when shooting into a bright light source. Don't expect anything exceptional though. You'll still lose a lot of detail in the shadows as with most lenses.
  • Sharpness at f2,8 isn't the best, but from f3,5 it's tack sharp until f11~f13 where it gets soft again.

Compared to Tamron 17-50/f2.8 and Pentax-M 50/1.4 all at f5.6, I'd say the 50-135 takes a close second behind the 50/1.4, but well ahead of the Tamron (which is a very sharp zoom lens).

*When I started photography, I noticed many people telling something like "shoot with a kit lens at f8 and it's as sharp as premium glass wide open". I have to disagree Even though it's a bit hazy at 2,8 there's a lot more fine detail visible. So don't trust that misbelief.

  • It's slow. There's no point in sugarcoating it. Not ideal for close range fast paced action @f2,8.
  • For everything else, it's more than enough. Goes from infinity to close focus in just over a second.
  • Sometimes it feels a bit laggy and has trouble locking focus.
  • More rarely, the lens might start and take the first couple of shots a little out of focus. Usually this issue goes away with a few seconds of focusing(AF).

*People have also pointed out it's not precise. I have to disagree. Having used a K30, K500, K50 and now a K3, the issue lies inherently within Pentax's own AF system. I can never be 100% sure I'll get pixel perfect focus. There's always a small room within which the AF system misses and catches focus and it has done so with all my cameras and different lenses. With fast glass these tiny errors show up more.
**My copy of this lens needed AF microadjustment. More on the older bodies, less on the K3.

Problems and FIXES

Let's start with the big one:

SDM failure

The good news is that in most cases the SDM doesn't die, it simply gets stuck. If you can't fix it via warranty and don't want to convert this lens into a screwdrive one, there is a simple fix available. I've made a separate blog post about it here: LINK

*this happened to me once and I fixed it

focus locks up

Turning the screwdrive screw on the back of your lens should do the trick.

*this happened to me once

Misses focus on some focal length, but not others

This indicates the zoom ring pins are bent or broken. See my link above, I also talked about this in my post. Again, it's an easy fix that doesn't require any mayor lens disassembly.

*never happened to me

Doesn't find any focus at all, only focuses inside a narrow range and doesn't respond to manual focus

I don't know why this happened, but I've read once or twice about it online too so I'm not the only one.
I just took the lens off and afterwards it worked perfectly again.

*this happened to me once

You might think this lens comes with a fair share of potential problems, but I assure you, all of them are rather rare and every lens regardless of manufacturer has problems like that. Newer copies of this lens have a better SDM that doesn't get stuck so easily. After doing a lot of research and meddling with the interior of my lens I'm convinced this lens won't magically break. For everything that happens there's a reason and most of the time the fixes are rather easy.

I recommend this lens. It's probably the best APS-C zoom lens for Pentax.

*I also tested it on the K1. The lenshood produces a good chunk of the vignette. Without the lenshood you can shoot @50mm and do a 1,1~1,2x crop to get rid of the dark edges. 1:1 crop has no vignette. Really, the vignette is not that bad without the hood. Works as a FF lens in the higher mm range. AND it remains sharp. So, no need to sell it just because you upgraded to a K1.
Senior Member

Registered: December, 2012
Location: Vancouver Island, BC
Posts: 237

5 users found this helpful
Lens Review Date: September 14, 2015 I can recommend this lens: Yes | Price: $325.00 | Rating: 10 

Pros: Near prime quality across a nice zoom range
Cons: SDM

Well, this is my third DA* purchase - already bought two DA*16-50 (one for me, one for my daughter)
This was bought used - advertised as only being Manual Focus as the SDM had died. Thanks to the members on this forum (and great threads documenting this technique) I bought the lens for a virtual song knowing that it was almost certain that I could get the lens converted to screwdrive and have a pro-quality AF zoom lens for about a third of the cost of a new one.
Once received, I tried "waking up" the SDM - unsucessfully, and after about 15 minutes of trying to revive the SDM mechanism decided that it was indeed dead, and proceeded to convert the lens to screwdrive by changing the lens rom. (look in the forum if you want to find out how)
About 30 minutes later the lens was whirring away happily on screwdrive - nailing focus and taking some really nice sharp pictures.
So... happy camper here. I wouldn't hesitate to buy this lens at all, as long as the prospect of having a somewhat noisier AF doesn't bother you.
Great handling, fast, sharp. And at the price I paid amazing value. Definitely a keeper.

Registered: April, 2016
Posts: 505

4 users found this helpful
Lens Review Date: January 7, 2017 I can recommend this lens: Yes | Price: $500.00 | Rating: 10 

Pros: Sharpness wide open, beautiful rendering, smooth bokeh.
Cons: SDM unit prone to failure
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 8    Handling: 10    Value: 10    New or Used: Used    Camera Used: Pentax K-3   

This is probably the best APS-C lens that Pentax have ever made. Nothing else comes close in providing the utility or quality that this lens provides. The colour, sharpness and bokeh are amazing. Like one reviewer put it, this lens makes a mediocre snapper look like a great one.

I've had five copies of this lens, all used. Three out of five have had SDM issues but all of these were easily fixed by opening up the lens and massaging the motor. Tutorials can be readily found for this procedure.

The copy that I now use exhibited a squealing motor as well as sluggish response to autofocus so I converted it to screwdrive using my K100d. Again, a procedure that is well documented. Autofocus is now much more responsive.

In all, this is the one lens I'd pick if I could only have one. It's equivalent to 70-200 on full frame so it's really not wide at all, but the images produced are out of this world. Ignore the autofocus issues. Screwdrive is worth the extra tiny bit of noise if your SDM motor dies. This lens is THAT good.
Veteran Member

Registered: May, 2011
Location: Las Vegas
Posts: 366

4 users found this helpful
Lens Review Date: March 21, 2012 I can recommend this lens: Yes | Price: $650.00 | Rating: 9 

Pros: Simply Irresistible
Cons: Heavy-ish.
Sharpness: 9    Aberrations: 9    Bokeh: 9    Autofocus: 10    Handling: 10    Value: 9    New or Used: Used    Camera Used: K20D   

Simply amazing.
After much debate with my wallet, I found a good deal here on the forums and took my chances even with the shaky SDM failure rate talk on the forum recently.
I lucked out. The copy is excellent and it does some amazing things.

I mainly focus on portraits, Cosplay Portraits, mostly. This lens packs quite a punch when used in 80-105 range, from what I've noticed. This lens suits my shooting style and I couldn't be any happier with the results. Shooting in the rain was just too much fun. While I was in the rain, shooting, other photographers were hiding under the cover and babying their equipment and complaining that they can't take photos. ahahahaha. WR rocks.

As with many Pentax lenses, bokeh is smooth and pleasing as usual. Nothing to complain about the Image Quality of this lens. Manual Focus is actually better than any other AF lenses I have ever used. AF noise is barely noticeable.
First time I used it (This is my first SDM lens), I thought the AF was broken because I didn't hear any sound nor vibrations from the camera

Couple of pictures taken last weekend.
The second photo was taken in the slight rain.

IMGP8341-2 by RickyFromVegas, on Flickr

Spike by RickyFromVegas, on Flickr
Site Supporter

Registered: November, 2014
Location: Washington, DC
Posts: 1,609

3 users found this helpful
Lens Review Date: January 10, 2020 I can recommend this lens: Yes | Price: $400.00 | Rating: 9 

Pros: Rendering; focal range; sharpness
Cons: autofocus

This was my first 'pro' level lens, and WOW is it a good lens! I had been using my HD DA 55-300 as an event lens, as it runs (if I remember correctly) around an f/4-4.5 for a good portion of its range. I found myself needing the extra stop of light indoors, and so I sprung for this lens. I was at first concerned, coming from the 55-300, that this zoom range would be restricting. This has not proved to be an issue in the least! It is a very versatile range with good quality.

I got it used with a failed SDM and had it converted by our good 'ol local Pentax Forums convertor, and now it runs great on screwdrive. It has a weird thing still that at 90mm it will back/front focus horribly - so I learned to avoid that focal length for autofocus. The focus isn't great, and I find it difficult to trust at f/2.8. Especially at 135mm, which isn't quite as sharp as the other focal lengths, it is easy to miss the focus by a hair. So I generally shoot at f/4, but f/2.8 is indoors doable with care, a monopod helps.

The rendition and colors are fantastic, so is the sharpness. It is a great lens. I've started taking this and the DA21 limited as a simple fairly compact two lens combo for events, and it works out really nicely. It has proven leagues above the HD DA 55-300, but there are still some impediments that I deal with for the low price I got it for.
Senior Member

Registered: May, 2010
Location: WA
Posts: 166

3 users found this helpful
Lens Review Date: October 1, 2019 I can recommend this lens: Yes | Price: $455.00 | Rating: 10 

Cons: Some report AF issues

I rented this lens in 2015 for a weekend trip to a race track. I needed a lens with moderate range, great image quality, and decent low light performance. My previous lens were good kit lens, the 18-135mm and the 55-300mm.

This lens surpassed all of my expectations.

Image Quality is fantastic. Great colors, excellent contrast, and sharp photos. I was amazed to see my test shot of a race car 500 feet away come out sharp. The lens rarely came off the camera the rest of the weekend. I came away with larger amount of sharp photos than I had previously done. The autofocus was great, weight was fine for hand shooting.

By the end of the year, I made sure to purchase my own copy. It has since been my go to lens, more so than my Tameron 70-200 F2.8.

My only complaint is that it stops at 135mm.

Junior Member

Registered: September, 2012
Posts: 29

3 users found this helpful
Lens Review Date: December 15, 2015 I can recommend this lens: Yes | Price: $800.00 | Rating: 10 

Pros: Great build quality, sharpness of prime lenses, weather sealing
Sharpness: 10    Aberrations: 9    Bokeh: 10    Autofocus: 8    Handling: 10    Value: 10    New or Used: New    Camera Used: Pentax K3   

One of the best Pentax DA lenses you can get! SDM still works great 5 years strong with lots of use.
IMGP0890 by Richard Mozis, on Flickr
IMGP0881 by Richard Mozis, on Flickr
Senior Member

Registered: May, 2014
Location: Galway - Ireland
Posts: 213

3 users found this helpful
Lens Review Date: August 17, 2015 I can recommend this lens: Yes | Price: $950.00 | Rating: 9 

Pros: IQ, build quality
Cons: AF
Sharpness: 9    Aberrations: 10    Bokeh: 10    Autofocus: 6    Handling: 10    Value: 9    New or Used: New    Camera Used: K3   

The 50-135mm is a great zoom for portraits and street photography. The range should also be great for press work and concerts.

This lens is big with the lens hood on, but still light to carry and work with. The focus rings are great, it is weather sealed, the construction is awesome.

This is the main limit of this lens : the AF is really sloooow (on K3). It is not usable for sports. Even for street photography it is not fast enough. It should be ok for studio portrait.
I manually focused for most of my real-life shots, but it is not what we could expect from this kind of high level zoom.


This lens is sharp from f/3.5. The sharpness is great at f/2.8 but not outstanding, wide open the image is slightly soft which makes it perfect for female portrait. The lens sharpness seems to be at its best in the 60-100mm range.

Bokehs are really great and soft, perfect for portraits.

No fringing and no major issues for me.

I did not notice any flare issue for this lens. Ghost is well controled.

Perfect for me ! Great rendering, a little bit warm.

Nothing noticeable in field conditions.

Nothing to care about...


>70-200mm APO Sigma f/2.8 EX
The 70-200mm provides the extra 135-200mm range that can be usefull in some conditions. The AF is really really faster than the 50-135mm, which makes this lens reliable for field conditions. However the image quality is not as clean as the pentax one because of fringing, ghost and flare.

> 105mm macro sigma f/2.8 EX
Using the 135mm at minimum focus distance, you can get some 'proxi' pictures. This is not the sweet point of the 50-135mm, so using the Pentax lens for 'macro-like' pictures is not a great idea, you should rather go for a macro lens.

If you can afford this lens and need a portrait lens, this one should be on your list for polyvalence and image quality. However be sure than you don't need a fast AF because it is the main limit of this lens.

Veteran Member

Registered: October, 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659

3 users found this helpful
Lens Review Date: August 3, 2009 I can recommend this lens: Yes | Price: $795.00 | Rating: 10 

Pros: Excellent IQ, bokeh, FL range ideal, water resistant
Cons: More difficult to use on a vertical oriented tripod head
New or Used: New   

I've had my DA 50-135 for 3 days now, and its everything folks said it was: great IQ, rendering, bokeh and nothing unusual in the focusing department (except that its extremely quiet)

I didn't have access to my computer equipment for the first day, so had to check image sharpness with the LCD. I noticed right away that i had to significantly increase my normal magnification to find a lack of sharpness. This seemed true till i reached the telescopic FL of 135mm.

Negatives from a few reviews:
a. There was one website review that observed on their copy that there was softness at 135 FL F2.8. I have a Pentax A 135 f2.8 which i think highly of so i took one handheld shot with the DA at 135mm and then 2 shots with the A135 f2.8 of a line on my deck 10 feet away. With 1:1 crops in Lightroom, i saw no difference in sharpness between the two lenses. With 2:1 crops in Lightroom, I could now observe that the A135 f2.8 images were sharper than the DA 50-135. (One review in Pentax Forums Database indicated that at F4 and above, the reviewer thought that the two lens were equal) In any case, i'm happy with 135mm focal length image quality.

b. One reviewer indicated that the hood was pretty flimsy in its attachment. I didn't notice that to be a problem. The hood attaches like a bayonet in the same way as the DA 300. It inserts axially, than rotates clockwise until it hits a partial stop, and then snaps into place. The action is lighter than in the DA 300 but adequate IMO.

c. One reviewer thought that the range should be higher than 135mm. Of course this is a personal thing. I spent one day walking along the shoreside of Port Townsend, taking architectural shots, and seashore scenes. In the long exposure nightime scenes that i enjoy doing, as well as the local playhouse stills that i take for them, this FL range is ideal for me. If anything, i would like to see a slightly wider FL.

d. The one complaint i have is that when i mount this on my tripod ball head, and then flip that ballhead over to a vertical orientation, i find that there is a tendency for the weight of the lens to loosen the camera body on the mounting stud. So this requires a firm tightening of the mounting stud collar and care in handling the camera body in the vertical orientation. Considering the many other virtues of this lens, its a small price to pay :-)

Here's one image of the DA 50-135 compared to the Tamron 18-250. The problem i had with using the Tamron for theater work, is that i often found myself at F5.6 and ISO speeds of 1600 and greater. With some F2.8 primes that i tried, one could work at ISO 800. Please note that on the first image, that i'm trying a 1 inch deep rubber hood from B&H instead of the provided plastic hood. Also note that the DA extends 5 1/4 inches from the mount to the end of the lens, not including hood. The Tamron, fully extended is about 6 7/16" long to the end of the lens. The Tamron weighs one lb while the DA is 1 1/2 lb. The reason for the comparison is that many Pentax folks have tried the Tamron or seen it and might be able to relate to the DA's physical size that way.

(Non working link deleted)

In the next image, the supplied DA hood is installed. Its 3 inches deep compared to the 1" depth of the rubber hood that i bought from another source:

(Non working link deleted)

The next image shows that the DA 50-135, installed on a K10 or K20 fits nicely into the Lowepro 200 AW slingbag with about 1/2 inch to spare. The rubber hood may be collapsed and left on the lens for storage while the plastic hood would have to be removed and stored in one of the pockets:

(Non working link deleted)

Finally, IMO, the following 3 lenses would make a nice light-weight walk around kit. Of course, many other light weight short FL lenses can be substituted for those shown.

Whether one likes to shoot with primes or zooms, i think we can all admire an excellently designed lens. The large shape of the DA 50-135 enables the lens to eliminate the normal telescoping 3 sleeves such as the Tamron design, which would be a nightmare to seal for water. The strong shell is likely to be more resistant to physical abuse than a telescoping design.

This lens is a class act all the way. The second day i had it, I used it to take portrait shots of 21 actors for a Shakespeare play brochure. The shots looked professional and got compliments.
Veteran Member

Registered: November, 2006
Location: London, England
Posts: 1,187

3 users found this helpful
Lens Review Date: December 27, 2007 I can recommend this lens: Yes | Price: N/A | Rating: 10 

Pros: Sharpness, colour, contrast, bokeh, weatherproof, silent
Cons: Size and weight

Overall: 10/10
A class act

Usefulness: 10
The APSC equivalent of the classic 70-200. Everyone should have one. great for candids, gigs, portraits....

Sharpness: 9
Wide open, it tails off in sharpness as you approach 135mm but overall its very sharp at F5.6 at all focal lengths. It really shines from 50 - 100mm. There are very few compromises here.

Colour/Contrast: 10
What really gets me about this lens every time is the quite exceptional colour and contrast. Stopped down a bit its hard to separate from a top ranking prime lens like the 77LTD, and even wide open its not too bad.

Bokeh: 9
The bokeh is exceptional for a zoom. Really nothing to choose between it and many primes in the same range.

Handling: 9
The focus ring is enormous - much larger than the zoom ring which is close to the body. Not really an issue but I sometimes grabbed the focus ring instead of the zoom when I first got it. However despite the size and weight it only needs 67mm filters and is well balanced with the C of G well towards the rear of the lens. A tripod collar is not really necessary.

Build Quality: 10
Excellent. Smooth and with very tight tolerances. Internal zoom.

CAs and Flare: 8.5
There is a bit of CA as reported but although its noticeable at the extreme focal lengths its not that bright and not an issue most of the time. Flare is minimal.

Distortion: 10
Not an issue at any focal length.

AF speed: 9
AF without USM is quite OK, but a little sluggish is low light. With USM it hunts less and is therefore faster although rotation speed is no different.
Site Supporter

Registered: January, 2013
Location: Ottawa, Canada
Posts: 2,682

2 users found this helpful
Lens Review Date: April 15, 2020 I can recommend this lens: Yes | Price: $850.00 | Rating: 9 

Pros: Optical qualities, Size, Focal length range, 'all weather'
Cons: Autofocus (see below)
Sharpness: 9    Aberrations: 9    Bokeh: 10    Autofocus: 7    Handling: 9    Value: 9    New or Used: New    Camera Used: K-3 II, K-5 II   

The Pentax DA* 50-135 was one of the first lenses that I bought in late-2011 after getting my new K-7, and it has been one of my most-used lenses. As a lens that I rarely leave at home, it easily receives c.a.m’s 4.5-star Gold rating of Highly Recommended!

The optical qualities are excellent. The lens is sharp across the field, with very good performance even in the corners at most settings. While the lens is usable wide open across the focal length range, I’ve noticed a slight softness at f/2.8 compared to other commonly-used apertures, especially at the longer end. However, I’ve never had a concern about distortion, vignetting, or aberrations, and the colours, contrast, and overall rendering are superb. In particular, the bokeh is typically pleasing at wide apertures.

At a mass of just under 700 grams, I find this lens to be comfortable to carry and handle. It is significantly smaller and lighter than my Sigma 70-200 f/2.8 HSM – which illustrates a strong benefit of the APS-C format. It’s a versatile lens that pairs nicely with my DA 20-40mm Limited. The lens has proven itself in a variety of shooting environments, including trail hikes, cityscapes, concerts, and portraits.

My copy was afflicted by autofocus issues four times during 2012-2013, during the height of many user reports of ‘SDM failure’. Warranty work included two new motors, cleaning, adjustments, calibration, and “gearing and clutch cam ring” repair. On the fifth instance, the AF seized again and the lens could not be focused manually. At that point, I converted the lens to ‘screwdrive’ mode, and it has worked flawlessly ever since.

I have conducted a rigorous AF Fine Adjustment (AFFA) calibration, assessing the settings at 50, 90, and 135mm; at focus distances of at least 30 x focal length; and variably focusing from the minimum focus distance and infinity positions. I found that the optimal AFFA setting varied according to focal length and focus direction; the optimal setting that gives the sharpest autofocus at all focal lengths is AFFA = +3 when focused from the near position. So, I simply preset the focus to the near side of the subject before each shot, which is an extra step but not a big deal. Note, however, that the AFFA is a function of both the lens and the camera acting together, so this issue may not be entirely a fault of the lens itself. This detail – and the SDM issue – is reflected in my lower rating of ‘7’ for AF.

The AF accuracy is typically spot-on and the shot-to-shot focus consistency is very good. I tend to take pictures mainly of static subjects, and I find that the autofocus is sufficiently quick and assured on my K-3 II. I don’t find that the screwdrive movement is annoyingly noisy, but it’s certainly more noticeable than the nearly-silent SDM mode. On the other hand, the screwdrive focus action is somewhat faster than the SDM, and it works.

- Craig

Site Supporter

Registered: July, 2011
Location: Melbourne
Posts: 778

2 users found this helpful
Lens Review Date: September 30, 2018 I can recommend this lens: Yes | Price: $1,150.00 | Rating: 10 

Pros: smooth bokeh in a compact lens
Cons: price

Well I used this lens for the September Single in challenge for the month of September 2018. I started off the month playing with this 50-135 2.8 hoping to finally see why people like it so much. After a month of shooting with it I have gained a respect for it. The photos taken at 2.8 seem to have a special quality about them, the way it handles areas of out of focus is very pleasing with a nice transition from in focus to smooth bokeh. The speed of autofocus and lack of hunting for focus worked well with my style of shooting. The size and balance with the K3 worked well and the lack of bulk made the combination easy to take with me each day. When I examined the photos closely I was unable to fault the sharpness of the lens other than due to using too slow a shutter speed leading to some softness from me rather than the lens. I can now see why it has such a great following. The silent lens focusing worked well for me and compared to the older screw drive mechanism, I found it very effective. The large zoom and focusing rings were easy to use and turn in the "correct" pentax way. Examples taken with this lens can be found in the following album
I highly recommend this classic lens

Registered: December, 2013
Posts: 795

2 users found this helpful
Lens Review Date: July 23, 2018 I can recommend this lens: Yes | Price: $610.00 | Rating: 10 

Pros: Sharp, fast, versatile, IQ
Cons: Big, heavy, slow AF
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 7    Handling: 9    Value: 8    New or Used: Used    Camera Used: K-30, KP   

This zoom lens excelent IQ. Near to primes. The zoom range is very versatile for portraits and from 70mm the F2.8 aperture gives sufficient background blur. The bokeh is excelent in the full zoom range. The build quality also very good, the zoom and focus rings are smooth, maybe the best I ever used on an AF zoom lens. The hood is bigger than what I would like, but the lens works well without it. In general I like the small primes, but this lens worst it. The AF is the only weak point of this lens, it's slow and occasionally I had acccuracy problems also. Overal this lens is the best zoom I ever used.

Here are some images:
IMG170422_0004 by Benjámin Czétényi, on Flickr

IMG170414_0056 by Benjámin Czétényi, on Flickr

IMG170603_0284 by Benjámin Czétényi, on Flickr

IMG170603_0190 by Benjámin Czétényi, on Flickr

IMG170603_0202 by Benjámin Czétényi, on Flickr

IMG170611_0002 by Benjámin Czétényi, on Flickr

IMG170923_0079 by Benjámin Czétényi, on Flickr

IMG170923_0029 by Benjámin Czétényi, on Flickr
Forum Member

Registered: December, 2012
Location: Warsaw
Posts: 83

2 users found this helpful
Lens Review Date: November 18, 2017 I can recommend this lens: Yes | Price: N/A | Rating: 9 

Pros: IQ
Cons: SDM failure.

New Member

Registered: August, 2010
Location: San Diego, CA, USA
Posts: 11

2 users found this helpful
Lens Review Date: September 7, 2016 I can recommend this lens: Yes | Price: $965.00 | Rating: 10 

Pros: Sharpness, color
Cons: Heavy
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 7    Handling: 9    Value: 9    New or Used: New   

It's been a spectacularly good experience owning this lens over the last 6 years. It never ceases to amaze me. Nothing makes me look like a good photographer more than this lens. Incredibly sharp and the colors never need to be corrected. The 3-D effect is something hard to find in a lens, but this one excels at it. Pixie Dust galore. I can't say enough good things about this lens!
Add Review of SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM Buy the SMC Pentax-DA* 50-135mm F2.8 ED [IF] SDM

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