| Author: | | Forum Member Registered: July, 2010 Location: Lubbock, TX Posts: 59 | | Review Date: January 27, 2011 | Not Recommended | Price: $53.00
| Rating: 4 |
| Pros: | Lightweight (all that it has going for it) | | Cons: | Really bad zoom creep, you can feel the plastic in its construction, hard to focus, REALLY bad CA and purple fringe, soft focus, dodgy IQ | |
Vivitar lenses are hit or miss with the few hits being really good, according to what I've heard. But this one is a big miss in my opinion. 
I bought this off of KEH right after I got my K-x just to try it out. It even handled and felt well on my K-x. After a bit of experimentation, I found that this lens only makes decent pictures at a distance of 10 - 12 feet (3.04 - 3.57 meters). The minimum focus distance is around 6 feet (1.82 meters).
The CA and purple fringe on this thing are horrendous (even egregious in a few cases), and plague a lot of the photos I've taken with it. The focus is really soft which makes for constantly fuzzy pictures. The zoom creep is really bad on this thing; among the other zoom lenses I own, this thing goes really fast on zoom creep. You can tell it's made of cheap plastic when you pick it up and hold it. It's hard to focus in a lot of instances and macro mode is hit or miss.
I've gotten a few good pictures with it, but overall, I wouldn't recommend this lens. Should you go ahead and buy it, beware that it has the Ricoh pin in it (PK-A/R mount), which requires removal before mounting on AF Pentax cameras, or else it will get stuck and leave you in a bad situation (fortunately I didn't have that happen to me, as I removed the pin).
Technical specifications were derived from the Canon mount version (which is the same thing, only with a Canon mount) from photographyreview.com (I'm giving credit where it's due).
| | | | | | | Junior Member Registered: May, 2010 Location: Bekasi Posts: 32 | | Review Date: April 5, 2011 | Not Recommended | Price: $45.00
| Rating: 4 |
| Pros: | usable | | Cons: | really low-res, feebly zoom scale, slow (ah well) | |
This Cosina built has many brand label as I recall.
Cosina, Tokina, Vivitar, Tamron, Phoenix etc. Also available in AF version, eh?
Same optics, I don't think one of them is any better.
It's too slow as long telephoto, impossible hand-held, dim finder.
Low-res, my shots with this lens enlarged to 5x7" look soft.
Seems designed as is 
Please accept it's destiny... | | | | | Pentaxian Registered: April, 2011 Location: Lost in translation ... Posts: 18,076
1 user found this helpful
| | Review Date: November 5, 2012 | Not Recommended | Price: None indicated
| Rating: 4 |
| Pros: | One touch, relatively small size ... | | Cons: | A lot ... zoom creep, etc. - see previous reviews - The Cosina version is slightly better ... | | Sharpness: 4
Aberrations: 4
Bokeh: 4
Handling: 5
Value: 4
| |
Bonjour,
I am not sure that I should even be reviewing this lens given the condition of the thrift store copy that I snapped up ... bought it mainly for parts, ie the rear mount assembly, in order to possibly convert another lens to a PK mount ... the front element coatings on this copy are in bad shape by either wearing off or just plain old age ...
I have a Cosina version of this lens which I gave a "6" and a negative recommendation ( see https://www.pentaxforums.com/userreviews/cosina-100-300mm-f5-6-6-7-mc-macro.html ). The Cosina version is more metal in its construction and thus feels and handles nicer IMHO. The test shots which this Vivitar version were not good at all, poor IQ, bland colors, etc.
Thus, even through my copy suffers from old age and maybe some abuse, I won't recommend this lens and give a "4" rating, which is harsh, yet true.
Allez et salut, John le Frog | | | | | New Member Registered: July, 2014 Location: Eau Claire Posts: 14
1 user found this helpful
| | Review Date: November 2, 2014 | Recommended | Price: $10.00
| Rating: 6 |
| Pros: | Inexpensive, Birding Lens | | Cons: | Terrible zoom creep, CA | |
I had just bought my first Pentax (body only) and has purchased one lens to go with the camera. The very next week I found someone on Craigslist was looking to sell their old pentax gear for $45.00. The gear included this lens and 3 others.
After the first week, I set this lens aside because I didn't like the results I was getting. With a little practice, I'm able to get some pretty good shots of birds out the back patio. For the price I paid for s lens with this type of magnification, I'm pretty happy.
 | | | | | | | New Member Registered: June, 2022 Posts: 10 | | Review Date: July 14, 2022 | Recommended | Price: None indicated
| Rating: 7 |
| Pros: | | | Cons: | | | Sharpness: 6
Handling: 5
Value: 6
Camera Used: k-s1
| |
I had it at home, someone buyed it in the 90's and it was never really used. I m trying to shoot with it with a K-S1. This was tonight, a village distant 9.5 km from me, shooted with a tripod. I think it can be adsolved and used sometimes, in given conditions it can do acceptable work.
Sorry about leaving all notes empty, not enough skilled to fill it... | | |
