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SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF] Review RSS Feed

SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]

Reviews Views Date of last review
26 130,426 Fri September 20, 2019
Recommended By Average Price Average User Rating
81% of reviewers $179.14 7.46
SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]

SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]
SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]

The SMC Pentax-FA 28-105mm F3.2-4.5 is faster than its Power Zoom version, but it employs a lighter design consisting mostly of plastic.

SMC Pentax-FA 28-105mm F3.2-4.5 AL[IF]
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Aperture Ring
Yes (A setting)
Automatic, 6 blades
12 elements, 11 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
AF (screwdrive)
Min. Focus
50 cm
Max. Magnification
Filter Size
58 mm
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 55-16 ° / 46-13 °
Full frame: 75-23 ° / 65-19 °
PH-RBC 58mm
Lens Cap
Plastic clip-on
Weather Sealing
Other Features
Diam x Length
66 x 66 mm (2.6 x 2.6 in.)
255 g (9 oz.)
Production Years
2001 (start of production)
Engraved Name
smc PENTAX-FA 1:3.2-4.5 28-105mm IF & AL
Product Code
28007 (black), 27997 (silver/black)
User reviews
One aspherical element.
Silver and silver/black
Screwdrive AutofocusInternal FocusingAperture RingAutomatic ApertureFull-Frame SupportDiscontinued
Sample Photos: View Sample Photos
Price History:

Add Review of SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]
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Senior Member

Registered: October, 2018
Location: Paris
Posts: 117

2 users found this helpful
Lens Review Date: September 20, 2019 I can recommend this lens: Yes | Price: $100.00 | Rating: 8 

Pros: compact, versatile range
Cons: optical quality in some situations
Sharpness: 7    Aberrations: 5    Bokeh: 7    Autofocus: 8    Handling: 10    Value: 9    Camera Used: K1   

This lens is really far from perfect but i like it.

Let's begin with what's wrong :
- Borders can be really soft especially at long end
- Chromatic aberrations
- Important vignetting.

So why still I use and like this lens ?
- This is a perfect zoom for travels : compact and versatile. I liked my tamron 28-75, I like even more my HD D FA 24-70, but they take a lot of place in a luggage ! What I gain, i use it to take some primes. This zoom is a lot lighter and offer a significantly longer max focal lenght.
- The colors here have really something. Forgot pixel peeping and look and the global result : this lens produce very bright images, and I still am surprised each time I use it.
- It's not a constant F/2.8 lens but F/3.2-4.5 is very usable without pushing the ISO too high when you lack some light, and you can even produce some bokeh

One picture is better than words : this one by nightime during a trip in Japan, with bokeh (at 60mm) and vivid colors in the background

So this is not the best lens you'll ever use, but you can rely on it for what it is good at : traveling, colorful pictures and even low light situations.
Veteran Member

Registered: April, 2007
Location: Toronto/Victoria
Posts: 312

1 user found this helpful
Lens Review Date: February 4, 2019 I can recommend this lens: Yes | Price: $125.00 | Rating: 9 

Pros: Surprisingly sharp, great value, great IQ
Cons: Build quality could be better, screwdrive AF, CA
Sharpness: 9    Aberrations: 8    Bokeh: 9    Autofocus: 8    Handling: 9    Value: 10    Camera Used: K-1   

I had a mediocre silver copy of this lens from 2005 on my *ist DS. I repurchased a black one used from The Camera Store for C$180 for my K-1 in 2017 and for the price it blew my mind.

It is a very compact lens for its range and speed (58mm filters). The IQ is excellent. Sharpness is surprisingly good all the way to the corners and the most noticeable weakness is a fair bit of red/blue CA. However, I'm happy to use it as a travel lens and would say its sharpness is better than my FA24-90 at the expense of slightly less versatile zoom range. They both have similar IQ overall including the CA.

The colours are also very good, and I've noticed that many ghostless SMC lenses share a similar trait that friends have historically referred to as "clean laundry".

The screwdrive AF is fine, but I've been spoiled by SDM/DC lenses. It also lacks WR/AW of course.

If you get a good copy and don't mind losing the modern functional features of the DFA28-105, this is a very good lens even for more than what I paid for it.
Loyal Site Supporter

Registered: March, 2010
Location: North-East of England
Posts: 16,157

4 users found this helpful
Lens Review Date: June 17, 2018 I can recommend this lens: Yes | Price: N/A | Rating: 7 

Pros: Film-era rendering, good contrast and colour, nice bokeh
Cons: AF hunting
Sharpness: 7    Aberrations: 7    Bokeh: 7    Autofocus: 6    Handling: 7    Value: 7    Camera Used: Pentax K-3   

I picked up my copy (in black) as part of a very inexpensive job lot from a local seller, and it came with the original hood.

It's compact, light and reasonably solid, although it doesn't feel as robust as the FA primes.

Optically, it's decent on APS-C. Colours and contrast are nice, and there's plenty of detail in the centre when stopped down just a little. Rendering is unusually decent given the class of lens. Out of focus highlights have a slight ring around them, which can often suggest bokeh will be rather "busy", but that's not the case here. At maximum aperture, out of focus highlights are circular, but become progressively more hexagonal as the diaphragm is closed down - yet they're never harsh or angular, suggesting that the blades are at least partially rounded.

Wide open, it's a little soft and displays "blooming" around bright edges. There's also some blue fringing in slightly out of focus bright edges, due to longitudinal chromatic aberration, and it's especially noticeable at longer focal lengths. Stopping down quickly reduces the extent of both effects, as you'd expect.

From 28 to approximately 70mm, the lens is actually usable in the centre wide open, but benefits significantly from being closed down one or two thirds of a stop to increase detail and reduce the effects of CA. Above 70mm, it really needs to be closed down by a minimum of one third of a stop for acceptable results, and two thirds of a stop for good results. Casual testing suggests it's at its sharpest in the centre around f/8 at all focal lengths, which is no surprise. For decent edge sharpness on APS-C at any focal length, expect to use f/8 and narrower.

The Achilles Heel of this lens is AF at longer focal lengths (especially the longest). On older bodies such as the K10D it will often fail to achieve focus, but even on my K-3 it requires a clear and contrasty target, especially in less than ideal light. As a result, one needs to consider the AF target a little more carefully than with some other lenses.

I can't speak for its performance on full-frame, but on APS-C it's a versatile and optically-pleasing lens if the focal length range works well for you. For a film-era zoom lens, it performs well, and I'm fond of the rendering - but I have no doubt whatsoever that the new D-FA28-105 will be far, far superior in resolution and CA correction, especially in the borders and corners. Which lens renders more pleasingly will depend on your personal preferences.
Veteran Member

Registered: March, 2010
Location: Bologna, Amsterdam, Chiang Mai
Posts: 1,108

5 users found this helpful
Lens Review Date: May 13, 2018 I can recommend this lens: Yes | Price: $130.00 | Rating: 9 

Pros: Quick AF, very good IQ for the price, rather fast
Cons: Not-so-great construction (like other "silver" FA zooms)
Sharpness: 9    Aberrations: 7    Bokeh: 7    Autofocus: 9    Handling: 8    Value: 10    Camera Used: K-1   

Just bought two examples, I will test them and probably sell one.
The first arrived a couple days ago. It's in spotless condition and with the original shade.
Paid 110 euros shipment included (about $130).
Many reviewers don't consider shipment, but it's part of the total cost, and should be included.
If we don't buy our lenses from a brick-and-mortar shop, usually we pay for VAT and/or shipment. I don't see why that expense shouldn't be added.
I don't own the new D FA 28-105mm, but I have read a post from a user who compared the two lenses. The most important differences are WR and faster, smoother AF. The IQ of the new one seems to be only marginally better.
My rating reflects that. If the new lens could get a 9, the old "silver" FA version deserves a 8.
I gave an overall of 9 cause some old reviews reflect a negative judgement due to AF problems with old digital bodies.
I briefly tried the lens on a crop body, a K-01. The AF worked as expected.

This is the first review on full frame. My first example of this lens works very well on my K-1. The AF is fast, in a kind of abrupt, violent way, because of the short travel. Sometimes I have the impression that it's focusing so fast that it gets past the point of accurate focusing, and has to adjust a little to lock perfect focus.
The lens is light and easy to handle, but it extends a lot to reach the longes focal.
The build seems to be in line with other silver zooms of the same generation. Though it seems better built than the other two lenses of the same "family" I already have (Pentax-FA f/4-5,6 35-80mm and Pentax-FA f/4,7-5,8 100-300mm). Unlike the other two, the 28-105mm has a metal bayonet, not a plastic one. Another difference is the presence of an aspherical element (the other two have normal glasses).
All three lenses have a better optical performance than their older F and FA counterparts. Considering the abysmal build it's quite a feat! The 35-80mm is very wobbly and plasticky, and the 100-300mm is also very cheaply made. I opened the latter to clean some fungus. In reality the problem was different (two flower-like principles of separation in a cemented doublet), but the group would have been uncleanable, because it's encased in a molded plastic abomination that can't be opened!.
The 28-105mm shares the same mechanical concept but is not wobbly and feels more substantial (I guess has more metal in it). Of course the pleasure of handling a K or A* series is miles away, but in the end it's not as terrible as I feared. The lens is quite pristine though, I don't know how it would stand heavy prolonged use.
The optical performance at 28mm and 50mm is very good for a consumer zoom. At 105mm it's not as sharp, but still more than decent at mid diaphragms. I expect some distortion at 28mm, but I had no time to test.
I didn't test vignetting either. From the first generic pics it seems well controlled, for a consumer film-era zoom.
The quality of my first round of pictures confirms my opinion. From my personal experience I can say that the latest generation of consumer FA zooms for film cameras were extremely well designed, and even on digital are definitely better than comparable zooms of the F and (non-silver) FA series. Because of the poor build quality, I'd stick with gently used examples (or buy hem from a reliable source).
I already knew that this lens performs very well on digital APS-C. I found that even on full frame the pictures are crisp, contrasty and with strong pleasant colours.
I shot all the photos with the hood on. The front element is very exposed, and the minimum focal is 28mm. The use of a proper hood is recommended. The original one is petal shaped, bayonet mount, and can be reversed. IIRC it should be possible to find a cheap compatible chinese hood on eBay, if the original one is missing.

I mainly use fast MF primes, mostly shot wide open (or barely stopped down), but there are situations, and subjects, that require the use of an easily portable AF zoom. I have 3 or 4 fast, recent objectives that rival primes in optical quality, but unfortunately they are huge bazookas Often I end up leaving them at home cause they take a lot of room and the weight is excessive.
The answer is to go out for a walk with a single "generic" zoom, or choose a couple of small zooms that will leave some room in the bag for more "specialistic" objectives.
In my experience, the Pentax-F 35-70, Pentax-FA 28-70 f4, Pentax-F 70-210 are all good enough to compete with decent primes, but this zoom is the only one with a range of focals wide enough to be considered a true generic lens.

As soon as I get the second example I will continue the test, and will edit this review according to my findings.
Would be nice to compare this lens with two other Pentax film era zooms I have: the earlier FA Powerzoom and the F 35-105mm (which has macro range).
To give an idea of the size of the lens at 28mm and fully extended at 105mm, and how it looks on my K-1, here are 3 pics:

Here one photo of a bad, bad boy who ate in a few hours half of a young jackfruit tree I planted in my yard (grown from the seed of a fruit I ate a few months ago).
This image show this lens at its worst. Closest focusing distance and zoom fully extended (105mm).
The optical performance degrades in a visible way approaching the longest focal. Optical quality is definitely better at 28mm and closer to infinity.
I think this is characteristic of the design, cause I received the second example, and it performs the same way. Sorry for the grainy picture, it was shot at 5000 ISO.

Caterpillar eating my tree by spaulein, on Flickr

K_1_4795 by spaulein, on Flickr

K_1_4809 by spaulein, on Flickr

The second photo is shot almost wide open, and it shows the great colours and the "pop" of this underrated lens.
The third gives an idea of the impressive sharpness stopped down.
All pics were converted to JPG (cropped and resized 50%), with basic PP.

Registered: June, 2013
Location: Nevada, USA
Posts: 3,348

8 users found this helpful
Lens Review Date: October 3, 2013 I can recommend this lens: Yes | Price: $100.00 | Rating: 8 

Pros: Excellent colors, very light weight, metal mounting surface
Cons: Feels fragile
Sharpness: 8    Aberrations: 8    Bokeh: 4    Autofocus: 7    Handling: 7    Value: 9    Camera Used: Pentax K-30   

This lens is a design of dichotomy. Let me cover them as pros/cons.

First and foremost, the greatest performance factor here is the color rendition. I don't know what Pentax did but they did it right. The colors are deep and vibrant without being saturated or artificial. I shoot in RAW and this makes post processing much easier. That said, if you wanted to go for an artistic saturation then it is very easy to achieve.

I found this lens to be decently sharp despite what others have said. It is at least on par with the 18-55mm kit lens in most situations. Maybe their autofocus needs adjustment? (i.e. front / back focus adjustment) Like any lens you should learn its strengths and weaknesses. Even a $1k lens used the wrong way can produce bad images. In general, you can f/8-it and forget about it. Slight aberrations are present in some cases but aren't terrible or distracting.

This lens is a bit larger with a f/3.2 opening. It's incremental probably over a f/3.5 but I'll take it!

It has plenty of hand holding reach at 105mm and is decently sharp there. Beyond that you should have a different lens anyways (and a tripod).

It has an aperture ring so this lens could be adapted to other systems.

The mounting surface is made of metal for those that care about that sort of thing.

The shortest focal length is only 28mm but it was designed during the film era for a film camera. From that perspective, 28mm is just fine.

Some would say that this is a con but I call it neutral. It does not have any macro capability. I think that for macro photography you should have a dedicated lens for that. Closest focusing distance is 6 inches which can still provide decent close-ups.

Mine came with the stock petal hood which is nice but I think any other petal hood would work too.

This lens does tend to cause focus hunting. I think its because the lens is so lightweight that the screw drive overshoots the focus point. The camera then needs to reverse the motor a bit only to overshoot again. Focus is achieved and it gets it faster than most contrast based systems but the hunting is noticeable. Some people have said that they hold their finger against the moving focus ring to slow it down. I use continuous focus and track my subjects. It works out well although this does drain the battery.

Being so lightweight the lens does feel fragile. Internal bits can torque and bend if you poke around with your finger. You can feel the mirror and shutter fire through the body of the lens. If all you do is handle the zoom ring then you'll probably be OK.

I wish the lens had a bit of a barrel extending beyond the body. The front element almost protrudes beyond the end. Put that lens cap on carefully!

Bokeh is there but it's nothing like a Helios 44M.

I think this could make a great walk-around lens. It's a great lens for events like birthday parties, weddings, nature walks, etc. The colors are phenomenal and that alone makes up for any cons that I could find with the lens! Focus performance can be iffy for some but I find it adequate. The lens is very lightweight which is good for carrying less heft but bad for durability. I would be hesitant to travel on an airplane with it unless I can hold it or have it in lens case and inside a durable travel case. I would happily recommend this lens with some warnings. This lens does not tend to appear for sale very often so I am happy I have it!

Nothing speaks better than samples. Here are some scaled-down images from my flickr account. There was very little post processing in most cases except for a tad of sharpening. The sunrises had some additional processing to balance out the extremes between light and dark and to exaggerate the colors a bit.

100% crop of a close focus

28mm wide angle view of a yard

1600 ISO shot at somewhat close focus of apples

Somewhat exaggerated colors from a sunrise

Nice blues from a sunset about to occur
Inactive Account

Registered: March, 2007
Location: Atlanta
Posts: 31
Lens Review Date: May 3, 2013 I can recommend this lens: No | Price: N/A | Rating: 7 

Pros: Good range, 3.2 @ 28mm
Cons: Won't focus on DSLR bodies
Sharpness: 8    Aberrations: 7    Bokeh: 7    Autofocus: 6    Handling: 6    Value: 7    Camera Used: MZ-5n   

This is like the tale of two lenses. It was my go-to walk-around lens in my film days. The silver finish complemented my MZ-5n well and I made quite a few really nice photos with it.
Once I moved to digital, I had to all but retire this lens as it had serious focusing problems with my *ist-d. It has the same problems with my K10 and my daughter's K-r.
I was really bummed.
Honestly though, I find that on crop sensor cameras, that 28mm short end isn't sufficiently wide for my walk-around lens.
Anybody with a film camera want to buy this?
Veteran Member

Registered: December, 2009
Posts: 325

1 user found this helpful
Lens Review Date: January 2, 2013 I can recommend this lens: Yes | Price: $180.00 | Rating: 8 

Pros: Color Rendition, Size, Weight
Cons: Sharpness
Sharpness: 6    Aberrations: 7    Bokeh: 9    Autofocus: 9    Handling: 10    Value: 10    Camera Used: K-7, K-5   

This lens is great for walking around. I've owned two due to LBA. As others have stated color rendition is definitely up there and bokeh isn't bad either! It's reasonably fast aperture is handy, but it isn't all that sharp and CAs can be an issue unless you stop down. Overall, the lens is a great value and a good, slightly faster alternative to the kit lens even though it is not sharper. The color rendition alone may make it better for some photographers.

The Pied Piper by Manila Vanila, on Flickr

IMGP2175 by Manila Vanila, on Flickr

Palace Hotel by Manila Vanila, on Flickr
Junior Member

Registered: June, 2012
Posts: 49
Lens Review Date: October 31, 2012 I can recommend this lens: Yes | Price: $150.00 | Rating: 8 

Pros: AF issue is not a problem on Pentax K-30
Cons: a little bit AF issues with K-r and K200D
Sharpness: 8    Aberrations: 8    Bokeh: 8    Autofocus: 8    Handling: 9    Value: 8    Camera Used: Pentax K-30   

This lens is a sleeper. I have a black one which produce awesome pictures and dovetails nicely with my black K-30. The AF issues, a little bit hunt at focal length over 80mm and apertures lower f/5.6, will gone, if you use it with the new Pentax K-30 .

Registered: February, 2010
Location: Northern Michigan
Posts: 4,795

15 users found this helpful
Lens Review Date: January 13, 2012 I can recommend this lens: Yes | Price: $180.00 | Rating: 8 

Pros: Superb color rendition; well suited for landscape work
Cons: Some optical shortcomings at the wide end; potential auto-focus issues
Sharpness: 8    Aberrations: 7    Bokeh: 7    Autofocus: 4    Handling: 8    Value: 9   

This lens is a bit of a sleeper. It does have some issues; hence the (relatively) low rating given by some of the other reviewers.

I bought the lens as an upgrade to the A 35-105/3.5. That old A series zoom, while a very fine lens, does tend to show its age in landscape work. The FA 28-105 enjoys the advantage of later technology, particularly in terms of flare control and color rendition.

Indeed, it is in color rendition that the lens really shines and the primary reason I purchased it. The colors this lens produces are somewhat unique in the Pentax lineup. Generally speaking, it features the usual FA, rather than DA, profile, with brighter blues and somewhat cooler colors than what we generally find with the DA lenses. What distinguishes the FA 28-105 from other FA lenses (excluding the star and limiteds) is the colors are a bit brighter and have more pop.

In terms of resolution, the lens tends to run from good to very good, except at the wide end of the lens, where border to border sharpness suffers, even at f8 or f11. The far corners also remain a problem through the entire range of the lens, even when stopped down. Likely, this problem would be worse on FF or 35mm film.

There's quite a bit of distortion on the wide-end. I haven't done any scientific tests, but I would contend that it's significantly worse at 28mm than the DA 16-45 at 16mm. CA issues also tend to create issues at the wide end, including some nasty red and green fringing that can be difficult to remove in post.

In short, most of the optical problems with the lens are concentrated at the wide end of the lens. From about 40mm to 90mm, the lens performs quite well, and it's more than decent at 105mm.

Build quality for the lens is, at best, merely adequate. This is largely a plastic lens which, unlike the A 35-105, will not likely stand the test of time. On the plus side, the lens is compact and light, coming in at less than half the weight of the A 35-105 and the DA 16-50.

The chief weakness of the lens, however, involves its tendency to exhibit autofocus issues. This is by far the worse autofocusing lens I've ever run across. While I can usually coax it toward accurate results in landscape work, in non optimal indoor light it's wildly inaccurate and hardly useable (at least with the K-5: haven't tested it on any other camera). Since I bought the lens solely for landscape photography, this is not a problem for me; but it may be a problem for others. (I would also note that not everyone has reported issues with the AF on this lens. For some people, the AF seems to work fine.)

How does the lens compare to others in its range? Below are brief comparisons:

A 35-105: The FA 28-105 is sharper in the center between from about 40mm all the way to 105. At the wide end, the FA is considerably less sharp as one moves away from the center. Throughout the rest of the range, the differences in border to border sharpness become less significant. The FA also has a bit more contrast and a clear advantage in color rendition. The 35-105 renders more nicely than the 28-105, with better bokeh, more attractive rendering of lines and transitions, and better rendering of depth. In other words, the A 35-105 is better for portraits and still life, the FA 28-105 is better for landscape.

DA 16-45: At 28mm, the DA 16-45 is clearly better across the board. At 45mm, the differences aren't so striking. Indeed, the FA 28-105 may be a bit sharper, particularly in the center. Neither lens has an advantage in color rendition. They render colors differently from one another, but both are, in their own unique ways, excellent.

DA 18-55: At 28mm, there's not much difference in center resolution. The DA kit zoom has a palpable advantage toward the borders, at least at close range. At longer focal lengths, resolution improves for the FA and worsens for the DA lens. Moreover, despite the slight resolution disadvantage at 28mm, the FA 28-105 nonetheless tends to produce better images at that focal length (and all others) due to better contrast and much more striking color rendition. There's more to a lens than just resolution.

Examples (all at f8):

At 28mm:

100% resolution:

At 50mm:

100% resolution:

At 60mm

At 105mm:

100% resolution:

New Member

Registered: March, 2011
Location: Tuktoyaktuk, NWT
Posts: 6
Lens Review Date: March 27, 2011 I can recommend this lens: Yes | Price: $70.00 | Rating: 9 

Pros: Light weight, internal focus, lens hood, non-rotating front element
Cons: Looks and feels a little cheap

Although I initially rated this as an eight, today I tried hard to find faults with this lens but couldn't so I am rating this a nine because the image quality is good with my copy and it focuses fast and accurately. No it isn't as good as the FA 28-70mm f4 but that lens is a constant aperture zoom which is a big plus. I find that I have gotten sharp images with decent contrast and no examples of extreme CA. It is even fast enough to use indoors without a flash as long as you use high ISO and noise reduction software.

I know the silver finish on my is a little cheap looking but the lens works, very well. I own a *istDL in the Canadian colour, silver, and this lens looks more at home here than on a black camera. The build quality is typical of FA lenses from that particular aesthetic era, a little loose and plastic but not to the point of causing any problems, and the internal focus makes it fast even on the old DL.

Overall I like it, it works very well on my DL and my K20D but will see very little time on that camera since it is practically welded to the *istDL. I understand that some people have had serious issues with this lens but when you get a good one it is very good indeed.
Junior Member

Registered: February, 2011
Location: California
Posts: 32

1 user found this helpful
Lens Review Date: March 10, 2011 I can recommend this lens: No | Price: $118.00 | Rating: 5 

Pros: Fast Focus, Light
Cons: IQ

I got this lens today. Took it out and did a dozen test shots against other lenses I have. It was obvious that I really is not producing clear, sharp images in comparisons. It is as weak as its plastic construction would make you think it would be. It won't be in the collection long.....
Senior Member

Registered: August, 2010
Location: Leeds
Posts: 152

1 user found this helpful
Lens Review Date: January 9, 2011 I can recommend this lens: No | Price: $180.00 | Rating: 4 

Pros: Nice zoom range, light and compact
Cons: focus problem

This is a lens I really wanted to like. I had a Sigma 28-105, but sold that to buy this (as I thought this lens would be better).

I have now bought two copies of this lens, and returned both. Basically, both have problems focusing - especially at the 105 end. At least 50% of the time it wouldn't focus. It would get to the point of focus, but then the focus confirmation light would flicker but fail to lock (similar to what happens if just slightly too close for a lens to focus).

I don't know if it makes any difference which camera this is used on, but I have a Pentax k-r. (Worried it was a problem with the camera, I took the second lens into my local camera shop and - with their permission - tried the lens on their K-r and a K-7, and had the same problem.)

Read more at:

Otherwise, I would have definitely wanted to keep this lens.

As such, I would only recommend this lens if you are able to try it first, to check it focuses okay (or at least check that you can definitely return it).

To be honest I wasn't sure how to rate this, but rated it on my experience.

As I have bought two copies of this, the price given is (roughly) an average of the two.
Forum Member

Registered: August, 2010
Location: Illinois
Posts: 53

1 user found this helpful
Lens Review Date: December 20, 2010 I can recommend this lens: Yes | Price: $160.00 | Rating: 8 

Pros: Good range, fast (for cheap zoom), IF, versatility
Cons: Some wide distortion

In my opinion, the Pentax SMC-FA 28-105 f/3.2-4.5 is underrated here, especially considering the very useful range and relatively fast speeds for a cheap zoom lens. Itís wide enough to capture a group of people only a few feet away, and long enough to get a headshot from across the room. I think that is its primary value- it is a good lens for taking pictures of friends and family at holidays, parties, and gatherings when I only want to bring one lens.

For picture quality, it is not as sharp as my primes or my 50-135 f/2.8, but at a fraction of the cost (used, if you can still find it) it is acceptable. The color rendition is natural. There is some distortion, especially at the wide end, but this did not bother me since I tend to shoot longer. Mine did not come with the original lens hood, but have not had any trouble with stray light or reflections.

The build is plastic and lightweight, but it is still solid enough. The operation is smooth and quick, and the focus is fast and accurate. I have really only noticed lens creep when I am mounting or removing the lens from the camera body. It doesnít seem to move while I am shooting. (My Tamron 28-75 f/2.8 is far worse in this regard, but has a zoom lock to compensate.) It does focus internally, which is especially nice for the price I paid. Aesthetically, the silver color makes it stand out a bit from the black camera body.

This was my walk-around lens until I got my 50-135 f/2.8, and I still keep this on my second body so that itís ready to go if I need it. I have used it for a wedding as a backup, and still got some great (and important) shots. It is not the best lens I own, but it is so versatile that I canít see myself getting rid of it until Pentax covers this same range again in a faster model.

Features: 8
Picture quality: 8
Build: 7
Versatility: 9
Inactive Account

Registered: October, 2009
Posts: 2

1 user found this helpful
Lens Review Date: November 28, 2010 I can recommend this lens: Yes | Price: $300.00 | Rating: 8 

Pros: Light, good range, fairly fast
Cons: Wobbly construction

I got this as a fairly cheap upgrade over the 18-55 kit lens. You lose 10mm at the wide end, but I don't do much wide angle shooting, and I really appreciate the additional zoom. I haven't done any scientific tests but the IQ to me looks at least as good as the kit lens, maybe better. It's also a bit faster than the kit lens.

When I have time to set up a shot I prefer to use prime lenses. They are faster in low light, have nicer bokeh and just look somehow better. But autofocus prime lenses are very expensive, so I have to use old manual ones, which are no good for capturing immediate action. Thus this is the lens I leave on my camera most of the time, ready for anything.

When buying a lens you have to compromise between: cheapness, IQ, zoom range. For me this a good compromise. You could probably get 18-300 range for a similar price but then the IQ would be lower. If you use the 200mm range then that might be a better option for you, but I use it so rarely I don't mind having to change to a difference lens for telephoto. I expect the new 18-135 has better IQ than this, but it's a lot more expensive.

Construction is a bit wobbly and the zoom mechanism allowed a hair to get inside the lens.
Veteran Member

Registered: March, 2009
Location: Salt Lake City, UT
Posts: 509

2 users found this helpful
Lens Review Date: October 3, 2010 I can recommend this lens: Yes | Price: $140.00 | Rating: 7 

Pros: Light, reasonably well constructed, close focusing, large range
Cons: So so IMQ

I have a FA 28-70mm f4. Let me use that as a comparison.

Positive side:
1. It is better constructed. Better fit and finish, even though the silver coating is less sturdy.
2. Very compact and surprisingly light with reasonably large apertures throughout the range.
3. Come with a lens hood which fits tightly
4. Internal focusing which means fast focusing and non rotating front element.
5. Better zoom range and the inclusion of AL elements allow more balanced performance throughout the frame (good corner).
6. A newer optical design

1. A bit less contrasty.
2. so so IMQ, particularly from 70-105mm. Some observable CA at the long end.
3. Hard to manually focus due to short focus ring throw
4. Hunt more in low light and focusing is not always very good in low light on my Kx digital.
5. 6 blades on the aperture. Does this matter to you?

All in all, a good walk around lens. But do not expect too much. Is it going to substitute my FA 28-70 f4? Probably not.

Would rate 7.5 instead.

Built: 8.5
IMQ: 7
Price/quality ratio: 8.5
Add Review of SMC Pentax-FA 28-105mm F3.2-4.5 AL [IF]

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