| Author: | | Pentaxian Registered: March, 2010 Location: Chiang Mai, Bologna, Amsterdam Posts: 1,198
11 users found this helpful
| | Review Date: February 15, 2013 | Recommended
| Rating: 9 |
| Pros: | everything, if used correctly | | Cons: | everything, if used the wrong way | |
After reading a few of the previous user reviews, i think it's better to try to understand what this piece of equipment was meant for. when it was manufactured.
Before buying any tool, the first thing to do is to realize what IT IS, and what IT IS NOT.
What it is NOT:
1) a conventional converter, there are cheaper and better choices, either 2x or 1.4x
2) good for zooms; even a conventional converter does not mate well with zooms!
3) a replacement for a full-fledged AF system: the focusing of the lens must be roughly adjusted beforehand
4) a converter for AF lenses (there is not such a thing - EDIT: sorry, i didn't check! I have seen them on sale... too expensive, IMHO)
5) compatible with slow MF lenses (it should not lock the focus with lenses slower than f/4.5, better if little faster, if there is scarce illumination... but i had success a few times with a f/5.6 lens, so i guess it's dependent on the amount of available light)
What it IS:
1) the only way to turn a compatible MF lens in an AF one
2) a decent 1.7x converter, if used with the "right" lenses
3) perfectly compatible with the electric contacts of KA lenses, allowing to use any exposure mode with modern DSLR cameras
Super-fast lenses apparently don't mate well with this converter, but i have little personal experience about it.
I didn't notice any particular problem with my 1.4/50mm M, but i didn't use it wide open with the AF converter.
I am sure that it performs admirably with a Tamron 2.5/90mm Macro, with P-KA Adaptall-2 adapter.
While high magnification macro photography is done strictly in MF mode, macro "hunting" at much lower magnifications can benefit from AF focusing (which allows to shoot quickly).
I have been very satisfied by the Tamron/1.7x AF combo: if we add the conversion factor to the crop factor of the APS-C sensor, we can get a powerful macro tele which allows to shoot small critter from a distance, filling the frame with the subject.
In such condition, a monopod and an off-camera fill-in flash would be extremely helpful.
I used the AF converter with a 2.5//135mm K, with decent results, but the best match are A lenses.
The way i use the camera, K and M lenses aren't exactly super fast to operate... so there would be little meaning in turning them into autofocus ones, to save one or two seconds!
The other lenses i own are not perfect candidates for the AF adapter, as wide angles (albeit sometimes usable as "normal" on DSLR) don't match well with optical converters. Retrofocus design isn't made for duplicators!
Most of the others, for a reason or another, are not good for this converter.
I must admit that i have a couple of A* lenses (1.4/85mm and 2.8/200mm) which could be a good match, but i never had the heart to bring them with me when i use the 1.7x AF. That is, when i leave for a naturalist/macro outing in the deep of the bush.
For other types of pictures, i prefer to use manual focusing, so the AF adapter isn't needed.
Someday i will test those lenses in AF/converted form, just for curiosity 
Depending on the lenses you own, and how you use them, this adapter could be either extremely useful, or worthless.
There are no other tools that can be used in its place.
For what it does, it does it extremely well, provided that you use it with the right lenses.
One advice: if you want to know in advance how this adapter would mate with your lens, and you can't find the right informations on the web, it is very likely that a lens that works well with a 7-elements duplicator, would also give a satisfying IQ with this AF teleconverter.
| | | | | | | Site Supporter Registered: October, 2010 Location: Paris, TX Posts: 39
9 users found this helpful
| | Review Date: January 20, 2012 | Recommended | Price: $125.00
| Rating: 8 |
| Pros: | good build quality; performs as designed | | Cons: | overpriced if $400; must carefully select lens used with it (i.e. 200/2.5, MF 300/2.8) | |
Back in the day Pentax had a mighty lineup of manual focus lenses for film bodies. Then oops Minolta started the AF revolution, Canon and Nikon jumped on board, and Pentax... well they created the little 1.7x AF Adapter.
Skip forward many years, and I wrote a review on this adapter. Today I am completely revising that review upwards. I have changed my mind about the 1.7x Adapter, rating it 8 instead of 7, and going with a 'yes' recommendation.. It could be because I'm thinking of selling my spare one soon.
Other reviewers tell about the pros and cons of this lens. They mention the occasional sky ooohigh price. If I were offered $400 I would try to tell the buyer he could spend less for something more useful. But the average of recent ebay 'sold' listings is a bit over $200, which could be a fair deal, counting for inflation since it first came out.
If you have a certain lenses it can be useful, though sometimes slow to get the shot. My favorites, with FF or digital crop factor, in no particular order:
A* 200/4 Macro [yummie]
M 200/2,5 [510mm / f5.1 in a small package, though heavy and slow to focus.
A 50/2 or A 50/1.4 - especially good full frame combos.
85/2
most any 90 - 100 lens: normal or Macro, MF or AF, f2.8 or 4.
M 300/f4
old Cult Classic Vivitar 90-180/f4.5 zoom, with tripod foot - see M200/2.5.
I never had the A 200/4 or the 400/5.6 so can't comment.
I tried it on my FA* 600/f4 several times but could not get the Adapter to quit hunting, not even with the 600 set to Manual Focus.
Look for my spare to be for sale somewhere, sometime. I just don't shoot much beside family snaps anymore.
| | | | | New Member Registered: February, 2012 Posts: 17
8 users found this helpful
| | Review Date: February 5, 2015 | Recommended | Price: $90.00
| Rating: 8 |
| Pros: | Works brilliantly with Pentax-M 50mm f1.4 | | Cons: | Less well with everything else I have tried ... | |
This gadget, that I bought in from an on-line photography site, launched my obsessive collecting of Adaptall lenses, so it has a lot to answer for.
In combination with the Pentax-M 50mm f1.4, I find it flawless. The combination is still fast compared with my usual consumer and bargain fare (about f2.3), it is compact, and it handles well. At events, I manually set the aperture and speed, prefocus to somewhere short of infinity, and then seldom have to adjust anything again. Autofocus is instant, I have no complaints with respect to its accuracy, and bokeh, sharpness and colours are all excellent.
Since I've been using an aggressive hood, I've come to prefer the look from the 50mm f1.4 to the 50m f1.7. I have a Pentax-A 50mm f1.7, and the combination works effectively, but to my mind the images offer nothing over the slightly slower Sigma 70-300mm f4-5.6 DG, which is at its best at shorter focal lengths.
As mentioned by others, the 1.7x AF requires the presence of a K-style aperture lever to activate the autofocus function, so it doesn't autofocus M42 lenses with adapters, or T2 lenses. With these it functions as a 1.7x Teleconverter. It's O.K., but I get better central sharpness from a Kiron 1.5x (though the Pentax is better than the other 1.5x TC I own).
If I mount a T2 or M42 lens on the 1.5x TC (which has an aperture lever), and then mount the TC on the Pentax-F 1.7x AF, it will autofocus if the lens is fast enough (f4.5), but the images that have resulted have been soft and lacking in contrast.
Although it is only specified to work with lenses f2.8 and faster, in my experience the Pentax-F 1.7x AF autofocus mostly locks on reliably, albeit slowly, when the lens wide-open aperture, after allowing for the adapter, is f11 or greater, on my Samsung GX-20 in good light.
Whether you will be able to discern more detail in the image created by the 1.7x than you would find in a 'digitally zoomed' version of an image taken without the 1.7x is another matter. Ones that pass this test for me are:
- Pentax-M 50mm f1.4
- Pentax-A 50mm f1.7
- Pentax-M 75-150 f4
- Pentax-M 80-200 f4.5
- Tamron Adaptall SP 70-210mm f3.5 19AH
- Tamron Adaptall-2 70-210mm f3.8-4 46A
- Tamron Adaptall 80-250 f3.8 Z250
- Tamron Adaptall 70-350 f4.5 CZ735
- Tamron Adaptall SP 300mm f5.6 54B
- Sigma 75-300mm APO f4.5-5.6
- Tamron Adaptall-2 135mm f2.5 03B
- Tamron Adaptall SP 90mm f2.8 72B
- Tamron Adaptall 200mm f3.5 CT-200
- Tamron Adaptall-2 200mm f3.5 04B
- Tamron Adaptall 300mm f5.6 'Auto Tamron'
- Tamron Adaptall 300mm f5.6 CT-300
- Tamron Adaptall SP 300mm f5.6 54B
- Tamron Adaptall SP 500mm f8 55BB
- Vivitar (Tokina) TX 400mm f5.6 first version (77mm, 8 elements in 8 groups)
Ones that I have tried, but which don't seem to play so well are all the other Adaptall, Adaptall-2 and Adaptall SP (60-85)-(210-300) f(3.5-3.8)-f(4-5.4) zooms.
However, for all of these with a maximum focal length of 200mm or less, it begs the question, why would you? For example, the Pentax FA 80-320mm f4.5-5.6 covers almost the entire range of any such lens used with the adapter, it will be faster, lighter (even than the Pentax-M 75-150mm f4 plus 1.7x AF combination), will concede nothing in image quality, and will likely cost less than the Pentax-F 1.7x AF on its own.
Out of curiosity, I also tried my long AF Telezooms, and compared them on their own, and with the Teleplus MC4 Pz-AF DG. The MC4 only autofocuses when the attached lens is f4.5 or faster, so the 1.7x AF, which works to f5.6 and beyond, potentially offers some additional reach. My results were as follows.
- The lenses are reported as A lenses
- You have to set the shake reduction focal length manually
- The aperture for the Sigma 70-300mm f4-5.6 DG could not be set successfully via the camera. The lens obviously made a complete hash of its PKA-compatible communication attempts.
- The two Pentax 100-300mm zooms seemed to work properly as PKA lenses
- The Pentax FA 100-300mm f4.7-5.8 wouldn't lock focus reliably past about 180mm
- The Pentax F 100-300mm f4.5-5.6 would lock all the way out to 300mm, and it gave the best images that I achieved with the 1.7x AF, but I got better results by 'digital zooming', and still better with the MC4.
In summary, my only unqualified successes, in so far as the combination gives me something that I cannot achieve more easily and cheaply in some other way are:
- Pentax-M 50mm f1.4
- Tamron Adaptall SP 90mm f2.8 72B in macro mode
- Tamron Adaptall 80-250mm f3.8 Z250
- Tamron Adaptall 70-350mm f4.5 CZ735
- Tamron Adaptall 500mm f8 55BB (needs a bright day and high-contrast target, but it works)
- Vivitar (Tokina) TX 400mm f5.6
And two of these make the grade because the manual lenses were such astonishingly good value.
When I am going out with just fast primes, I do pack the 1.7x AF for the potential additional reach, and to fill the gaps, but I seldom deploy it.
So, whilst I recommend the Pentax F 1.7x at the price I paid for it, I would never be able to justify paying $200 plus.
| | | | | Senior Member Registered: August, 2007 Location: Los Angeles Posts: 233
7 users found this helpful
| | Review Date: January 15, 2013 | Recommended
| Rating: 8 |
| Pros: | Grants limited AF to MF lenses. Not a 2X teleconverter | | Cons: | Can't use as teleconverter for AF lenses. Doesn't work for screw mount lenses either. | |
This is a really strange animal.
For years, I held off on getting one because the prices are so high and I generally don't like teleconverters that much (due to the lost of quality and my being a wide angle guy).
That being said, I really love manual lenses and having even limited AF on them sounds really appealing. Finally, I found a good price on one and decided to give it a try.
This thing gave me one pleasant surprise and two bad ones.
Good news first: The lost of quality is pretty minimal, better than most teleconverters and better than a 2x tele for sure. Also, despite its limited AF capability, it is pretty easy to focus into "close enough" range for this thing to take over. For "A" class lenses, it also correctly translates the f-stop to compensate for the loss of light.
Bad news 1: This thing can't be used as a teleconverter for natively AF lenses unless you want to lose your full AF and live with a "limited" AF! I was shocked that no one ever mentioned this! When mounted, the camera's AF only moves the AF of the teleconverter, the screw doesn't reach the actual lens at all, so now your normally fully AF lens is a limited AF lens! (I guess I should have downloaded the manual before buying, but it just never occured to me.)
Bad news 2: This doesn't work with M42 screw mount lenses even though you have an original Pentax M42 adapter. Apparently, the aperature lever clicks something on this thing and it allows the AF function to engage, since M42 lenses don't use the K mount aperature lever (it uses a pin), it just functions as a Non-AF teleconverter if you mount screw mount lenses to it. This sucks.
If you use this thing with "A" class lenses, it works just as advertised. Allows you to focus almost as quickly as an autofocus lens for the price of 1.5 stops of light and a 1.7x magnification.
If you use it with "M" and "K" class lenses, it still works OK, of course you have to use your camera in M mode with the green button unless you just shoot wide open.
If you use it with any autofocus lenses, you've just downgraded your lens to a semi-autofocus lens.
If you use it with any M42 screw mount lens, then it's just a plain old dumb tele-converter.
So the guy who wrote the review saying that this isn't a teleconverter was correct. This is a device meant primarily to convert "A" class lenses to partial AF lenses. It just happens to provide 1.7x maginification. In that regard, this thing works just perfectly.
| | | | | | | Site Supporter Registered: November, 2010 Location: California Posts: 2,223
6 users found this helpful
| | Review Date: April 20, 2011 | Recommended
| Rating: 10 |
| Pros: | It convert manual lenses into Autofocus and also multiplies the focal lenght | | Cons: | Takes almost 2 f-stops of light | |
The reason I chose Pentax over Canon is because I could make some manual lenses AF with this converter. So, this is a must have adapter. This lens is like a wife, it it good but this or that, but you have to have one. Really, this lens works fine with my Pentax M50mm, f1.4, f1.7, f2, M28mm f2.8, M135mm f2.8, M200 f4, but did not work well with my Pentax M400 f5.6 although it tried. It works fabulous with my Manual Tamron Adaptall SD 300mm f2.8. Sometimes I wish it were 1.4x instead of 1.7x. I hesitated to buy it, but after a while, and after having the 300mm f2.8, I had to have it. So, go and get yours quickly. It also works well with all my FA and A lenses. It is a must with my PKA and my Adaptall lenses. I have two and looking to get one more.
The photo below was taken with my Tamron 300mm f2.8+ the 1.7xAFA
Update:
Here is a photo with the Vivitar 105/2.4:
 Vivitar105mmf2.5&PX1.7xAFA-BigFly-1 by Palenquero, on Flickr
 Vivitar105mmf2.5&PX1.7xAFA-Moth1-1 by Palenquero, on Flickr
| | | | | Site Supporter Registered: February, 2010 Location: Salt Lake City, UT Posts: 1,915
5 users found this helpful
| | Review Date: August 16, 2010 | Recommended | Price: $350.00
| Rating: 8 |
| Pros: | Af for any lens. Pairs well with excellent primes and some zooms | | Cons: | Don't use it with glass faster than 2.8 | |
This, as with any TC is somewhat of a mixed bag. If you throw it on a lens with already mediocre performance, you'll be sorely unimpressed.
If you choose solid glass, this TC will provide you with stunning results.
A few notes of caution. I've not had much success with glass faster than 2.8. At that point you're better off just getting your somewhat longer glass out anyway.
When attached, this makes your lens behave as an A series lens, and you must manually pick the focal length. Therefore, it's not a great choice with zooms unless you're sticking to one end of the focal length. (It will make your SR over or under correct essentially).
The built in AF usually requires you to make a first "close" focus adjustment yourself. This tends to work out fine for me, but your results may vary. It seems to work with 2.8, 4, and 4.5 glass quite well.
Although you have to pick the focal length, the TC does adapt the aperture, so it will appear mostly correct in your exif data.
Once you understand these limitations, this TC can create some excellent results.
One more thing to note, with slow glass, I've found the AF accuracy in liveview outperforms the AF in the viewfinder on my K-7. I was getting surprisingly good results taking pictures of the moon with this attached to my 1000mm F/11 Reflex and letting the TC handle the focusing in live view. Perhaps even better than if I had tried to focus it myself.
| | | | | New Member Registered: October, 2020 Posts: 4
4 users found this helpful
| | Review Date: March 18, 2021 | Recommended | Price: $250.00
| Rating: 10 |
| Pros: | Doubles your number of lenses, maintains or improves sharpness | | Cons: | PF, quite a fragile build on it, AF only works on K mount | |
This piece of glass is a joy to use. Snap on a lens to it and instantly have a new one with a new focal length and max aperture. I use my Vintage Auto Sears 50mm f1.7 on it and get an Auto Sears 85mm f 2.55 lens which auto focusses. Snap on a vintage 50mm 1.2 and get an auto focus 85mm f1.8 (which would be awesome). There is no noticeable loss of sharpness from the original lens.
The converter seems to produce some PF though which is very negligible and can easily be fixed in PP. My major complaint on the converter is that it will only auto focus on K mount lenses. Pentax has a lot of awesome lenses in M42 mount. The converter will not auto focus on an M42 lens with K mount adapter snapped on to it  Another flaw on the converter is it has major difficulty giving AF on macro lenses (or lenses with a very long focus throw). The build quality is on the fragile side.
The converter does not come cheap but is such a joy to use. I can just imagine snapping a Pentax A* 300mm f4 on to it so I can get a Pentax A* 510mm f6 with auto focus
Image uploaded was taken with the converter and my vintage Auto Sears 50mm f1.7 lens
 | | | | | New Member Registered: January, 2012 Posts: 4
4 users found this helpful
| | Review Date: January 27, 2012 | Recommended | Price: $400.00
| Rating: 9 |
| Pros: | gives me a good portrait lens with 50mm f1.7 | | Cons: | none | |
I got this gadget on a hunch -- one of those impulse purchases on e-bay. When I combine it with with my manual 50mm f1.7, it becomes an f2.8, 85mm lens -- very useful for portraits on my K5.
But here's the absolute plus: the portraits that the combo creates are much more interesting attractive, and warm than those same subjects taken with my 77mm ltd. I love the character of these new pics. The colors are more accurate, the subjects more calm and alive than in pics with the more clinical 77mm -- a lens I also like.
The combo has become a very special lens for me.
| | | | | Junior Member Registered: November, 2008 Location: Lyon, France Posts: 31
4 users found this helpful
| | Review Date: March 11, 2011 | Recommended | Price: $350.00
| Rating: 10 |
| Pros: | AF magic, good IQ, mag 1.7, bokeh | | Cons: | High cost | |
This the main reason that I switched from Canon to Pentax, and I never regret of that.
This magic TC transforms any manual lens to semi AF lens. Only in Pentax, Nikon has the same thing, but it is very difficult to find.
Pros:
+ Transform MF lenses -> AF lenses.
+ Can works with lenses faster than f4.5 even f5.6 (in very good conditions)
+ Magnification 1.7x
+ Very good IQ, (I rate the IQ about 9.5/10)
+ Can deliver "Excellent" bokeh with some lenses which have "Ugly" bokeh (e.g my Minolta 50mm 1.2 has very ugly bokeh, but in couple with this TC, it allows very smooth bokeh. cf photo)
+ Transform automatically the aperture.
Cons:
- High cost.
- Difficult to find.
Photos:
With Minolta 50mm 1.2
With Kiron 105mm 2.5
| | | | | Veteran Member Registered: September, 2017 Location: Medellín Posts: 1,322
3 users found this helpful
| | Review Date: December 23, 2019 | Recommended
| Rating: 10 |
| Pros: | Build quality, compatibility, unique. | | Cons: | | |
This TC really sets Pentax apart, since it turns any manual lens into an AF one. Works great on my K 135/2.5 and turns it into a 230/4,2 AF assisted lens. My A 50/1.2 turns into an 85/2. A three MF lens kit turns into a five piece (2 AF).
Side note: You should only really be shooting this with normal to tele lenses, since shorter focal lenghts is not what TCs are for. Shorter focal lengths have mor DoF, thus are more forgiving in terms of nailing the perfect focus. This is why this adapter comes in handy with longer focal lengths.
| | | | | Pentaxian Registered: April, 2015 Location: USA Posts: 2,875
3 users found this helpful
| | Review Date: June 25, 2018 | Recommended | Price: $350.00
| Rating: 10 |
| Pros: | fairly fast, dead on accuracy, works on adapted Zeiss & Leica R lenses | | Cons: | need to prefocus the lens manually to the approximate distance before hand - this adapter only will "fine tune" the last little bit | |
.
I only shoot manual-focus, premium, prime lenses. However, there are occasions when I find that it would be handy to be able to shoot an auto focus lens. Also, with my old eyes getting worse by the year, I'm beginning to think auto focus lenses just might enable me to take photos further into my golden years.
That said, I sure don't want to have to give up the incredible image quality I'm getting with my adapted Zeiss and Leica R lenses just because of aging eyes. What am I to do?
Well, I just discovered how I can have my cake and eat it too. In other words, use my adapted Zeiss and Leica R lenses in the AF mode.
A few months ago I purchased a Pentax SMC Pentax-F 1.7x AF adapter. Never shot it "until today".
Below is the first photo I took with it. I attached this little adapter to adapted Zeiss ZF 35mm f/1.4 lens, and attached this combination to my Pentax K-1 camera, and shot away at f/2. WOW, am I impressed! The auto-focusing was fairly fast and dead on accurate. As many of you know, the Zeiss "Classic" ZF 35mm f/1.4 lens (with heavy Leitax adapter) is a fairly large and heavy lens - but this little adapter had no trouble at all with it.
Just put your camera in the AF mode and fire away (well, it does help if you manually move your lenses' focus adjustment to somewhere close to your shooting distance before shooting). My favorite way to use it is in Live View with back button focusing. Another side benefit to using this AF adapter is that it will speed up the taking of photos a little bit (not as much as a fully auto-focus lens, but maybe half way between an AF lens and the MF lens without this adapter).
Some of you will ask, "does this adapter reduce the image quality of photos taken with it?". This AF adapter does have 6 optical elements in 4 groups inside of it. Being an expensive Pentax product, it is well made with premium optical glass inside. Having said that, if you are a pixel peeper, maybe you will be able to detect a tiny TINY drop in sharpness if you look really hard. So, if you are a photographer who demands as much sharpness out of their gear as is possible, then you may want to not use this AF adapter. However, the great majority of photographers will not be able to detect a reduction in an image's IQ by using this AF adapter.
While many of you are already familiar with this AF adapter, I guess that I thought it would not work on my "adapted" Zeiss and Leica R lenses. Well, I'm here to tell you it works just fine on adapted Zeiss and Leica lenses. So, if you love Zeiss and Leica R glass like I do, here's a little accessory that you just might want to consider trying out for yourself (especially if your eyes are not what they used to be)!
.
.
| | | | | Forum Member Registered: January, 2011 Location: United States Posts: 63
3 users found this helpful
| | Review Date: July 13, 2011 | Recommended | Price: $50.00
| Rating: 10 |
| Pros: | Amazingly little quality loss, adds AF to manual lenses, reasonably fast AF | | Cons: | Nothing really | |
I have found a NEW unused copy of this beauty online. It was marked down CLEARANCE for $30 and I paid $20 for overnight shipping. For the price I paid, I must say, this is a spectacular piece of glass.
I have a nice collection of Pentax A lenses (50mm 1.7, 28mm 2.8, 135mm 2.8) and this converter adds autofocus to all of them at only one and half stop light loss. Having this adapter is like having three more primes that has AF. I have always liked manual focus lenses better than AF lenses, so having to approximate focus first does not really bother me. I have also tried this with my DA 18-55 and 55-300 and Tamron 70-300. Works alright with them as well. Since these are not very fast lenses, the performance is not nearly as good as my fast primes. I don't use my zoom lenses very often anyway.
Overall, I think this is a great addition to anyone's collection. And, if they have Pentax manual lenses, then this is a MUST as it will produce incredible versatility.
| | | | | Site Supporter Registered: November, 2008 Location: Tasmania, Australia Posts: 8,209
3 users found this helpful
| | Review Date: January 25, 2011 | Recommended | Price: $254.00
| Rating: 8 |
| Pros: | Adds autofocus to A lenses and earlier | | Cons: | Applicable in IQ terms mainly to longer lenses | |
After reading much discussion (some good, some not so good, and some odd - I don't see the point in reviewing something that is only half-working, for example) on this Forum, I decided that, on balance, this TC would be a good addition to my long-range kit. I haven't really been disappointed with the results, but one has to exercise discernment in choosing which lenses it's attached to.
I've used it successfully with my A400/5.6 and on my smc-Tak 135/2.5, with good resultant sharpness and only a tiny loss of contrast. It's really pointless (unless you're desperate for the shot) putting it on anything shorter than that. I've also tried it with usable success at the lower end only, of my K400-600 cat, but that lens isn't the sharpness king at the best of times, and I could simply zoom it to the same focal length, anyway (it might just be usable at the long end in brilliant sunshine).
Exposure compensation, as others have mentioned, is necessary on some lenses, but that doesn't pose much of a challenge to any photographer worth their salt.
It's a necessary adjunct to most Pentax shooters kit, in my view - I'm sorry I didn't get one earlier.
| | | | | Veteran Member Registered: March, 2009 Location: Salt Lake City, UT Posts: 509
3 users found this helpful
| | Review Date: April 22, 2010 | Recommended | Price: $300.00
| Rating: 9 |
| Pros: | Fast AF, decent IQ, and creative design | | Cons: | Some limitations; work better with some lenses | |
This is a controversial and unique item. Some reviewers seem to have negative experiences. Mine has been good so far. If used properly, it creates reasonably good images (perhaps not as good as the best dedicated Pentax converter). Does Pentax make any AF converters? Not to my knowledge.
It is unique in design, bridging the gap between a large number of MF Pentax lenses and AF. It is perhaps more suitable for A series lenses. I have found good results on some lenses.
There are some limitations to the use. So make sure to understand the limitations before use. For instance, it is perhaps not good for f1.7 or larger apertures. The glass in the rear seems quite small (much smaller than that of my 50mm f1.2). This may explain why the use with my 50mm f1.2 creates quite soft images at the maximum aperture. However, it may not be a bad thing for portrait shots. The image quality improves dramatically by lowering just one stop. It does not work well in low light or with lens f4 or smaller. It does not work well with zooms. (Think about the number of glasses combined!!!). Finally, it only support a number of lenses outlined in the brochure.
[edit] It works much with some lenses than others. It works best with my standard primes and 100mm f3.5 macro. It did less well on my 135mm f2.5 and my 200 f2.5 (to my surprise). I will explore more about the combinations. I suspect that this might be the reasons for the varied opinions and results.
First two examples were with my 50mm f1.2.
The 3rd one was 100% crop of the 2nd. The last one was taken with my 50mm f1.2 at the largest aperture (f2.8--do not ask me why). It is 100% crop. Not bad ehh!
EDIT: Increase my rating to 9 due to the fact that it works very well with DAL35. When stop down a bit, its images are as sharp as those of any other prime lenses that I have. Moreover, it makes DAL35 a quasi macro lens.
Note: the noise is due to my K10D and high ISO.
100% crop
Kx DAL35 + F1.7X f10 1/500s ISO:200
 | | | | | Site Supporter Registered: February, 2008 Location: MT Posts: 1,350
3 users found this helpful
| | Review Date: October 17, 2008 | Not Recommended | Price: $110.00
| Rating: 5 |
| Pros: | helps modernize early lenses to autofocus | | Cons: | big sharpness decline with * lenses | |
I'm being nice scoring this "toy" a 5. If you want snapshots, family photos or pictures of a bird sitting on a power pole in front of your house, this thing must be OK--judging from the high demand and positive forum talk. HOWEVER, if you are trying to take publication quality images for magazines or ads don't bother with this teleconverter. I've tried it with A*200/4 Macro; A*300/2.8; and F*600/4 (for magnification not autofocus), and never got a single "keeper" photo. All images are noticeably soft to the point of not being saleable. Comparing results from this 1.7x to the 1.4XL proved the 1.7X to be vastly inferior. Sold mine for $40 back in the '90's, and don't miss it a bit.
Perhaps the razor sharp images of the * lenses makes the less sharp 1.7X versions seem worse than they really are. Perhaps this product is optimized for use with "standard" consumer lenses? Pentax didn't promote this as a "pro quality" product like they did the XL teleconverters so perhaps I'm just too picky and have unrealistic expectations. Also, 1.7x is considerably more magnification than 1.4x so it should have more image degradation than a 1.4x. Still, if I can't at least attempt to sell images made through it, then it has no use in my kit.
Beware of this item as it's getting lots of positive forum talk.
| | |
