Aldo R. Perez says:

First let me say that my first copy of this objective is entirely bad, throughout almost all soft at f / 8. 0. My second copy behaves very bien.Estoy using this lens on a Pentax K2000 (Km in Japan), which has the same sensor that the Pentax K200. Other lens I have several but my best lens is a SMC Pentax-FA 50mm f / 1. 4 and define clarity, color and contrast depending on the quality of this lens (one of the best 50mm primes). In f / 2. 8 is soft in the center or corners depending on the focal length. However, the test also shows the potential of small images after sharpening, especially in the shorter end. My Pentax SMC-FA 50mm f / 1. 4 provides much better images at f / 2. Q # 8 f / 4. 0 todo so much improved, especially the center sharpness, but there are signs of some weakness in the extreme corner in some focal lengths. My Pentax SMC-FA 50mm f / 1. 4 is even better at f / 4. 0.en f / 5. 6 This goal can go “hand in hand with my Pentax SMC-FA 50mm f / 1. 4, and sometimes I think the Tamron is better. I suspect that both objectives are higher resolution camera sensor in this opening. The fact that this quality in this opening is so consistent throughout the entire focal length gives muchos.en Tamron points f / 8 lens acts a little strange. In some longer focal lengths, is almost as good as when used at f / 5. 6, while the shorter end is lost in quality. Totally usable and remains good at f / 8, but the unexpected loss of quality is on the short end, better than the f / 4. 0 in the center without the soft corner in the short end, but not as good as f / 5. 6.en the sharpness is excellent, and to f / 5. 6 – P / 7. 1, very good and still good f/8-f/11 with little distortion f/13-f/16 that hablar.Macro is very good in 75 mm f / 8.Mi biggest problem with the lens are: the first copy was bad and people write similar experiences. That is the quality control is not buena.Mi second issue is that from the standpoint of expectations, at least in my Pentax K2000, the objective seems to be a good constant f / 4 lens with f / 2. 8 in case of emergencies. I would avoid using the f / 2. 8 opening if possible (remember, I have a SMC Pentax-FA 50mm f / 1. 4 lens and used to very good quality at f / 2. 8). Now, since I paid $ 400 for the lens and that’s more or less what Sigma charge for a similar purpose and 2 / 3 ’s of what they charge for their Pentax SMC Pentax-DA 17-70mm f / 4 to the SDM (which is a bit soft at the longer end, but wider at the short end) this is a good compra.Si not for the quality control issues to achieve this objective would be a simple “yes”. As it stands, I like thinking about it and be ready for testing and return if necessary. If you get a good copy you could find a good valor.Si would give this objective 4. 5 stars and not 5 for quality control issues. Moreover, the images look really once I get a good copy. Rating: 5 / 5

dan says:

likes: it feels very solid, well built. constant 2. 8 opening. when acute, its very very fuerte.No Dislikes: front focus / back focus issues. Fortunately, the K20 is capable microadjustment lens, which helps a lot. very heavy. pettiness, but I would like the zoom of 18mm. 28 is inconvenient for the purpose grupo.Comprado photos of the wedding, and it definitely helped. When his sharp, his incredibly sharp. The “bokeh” is great. Some shots at 2. 8 (established in the central focus point), was 10 feet (about me), that is completely ridiculious, but were friendly when it was worth it. I do not buy this camera that lets you adjust the focus setting automático.Calificación: 4 / 5

Daniel J. Tripp says:

I recently started wedding photography, and this goal does the job. It does a great job in low light. I’m very glad I purchased this goal, it was well worth the money. Rating: 5 / 5