K5 and sigma lens problem and kennedy's

[ricstew]

my 28-70 2.8 ex is giving me the pip.........I cant get it to focus properly at the 28mm, 34 or even 50mm.......70mm seems ok........it worked fine on my Pentax KM but not on my K5.......so has anybody dealt with Kennedy's over an issue like this. This is a replacement lens.......( replacing one that didnt work ) purchased originally 09/08/2010......at Camera house in Melbourne
cheers
Jan

[bdparker]

I had the same issue with my K-7 and my sigma 17-70 2.8-4.5 macro. Sent both to Kennedy's (there were other issues with my camera as well) got them back the week before Christmas (within 2 weeks), all done under warranty and no charge. Camera all good but still not happy with the lens, but I think I'm expecting my lens to perform better than it actually can.

[ricstew]

Thanks ?Barry.........I know this lens is as sharp as sharp at least on the KM/K2000........on the K5 its a dud

[ricktas]

Kennedy's have a good reputation!

[ricstew]

Thanks Rick.......I have never dealt with them......and as silly as it sounds I don't need to be told I am imagining it
cheers
Jan

[pixy]

Is it a front focus /back focus issue,you have in the camera adjustment for this, which can be applied to each lens, if you don`t feel comfortable doing this your self you can send the camera and lens to Kennedy`s for adjustment,maybe a phone call or email to them and seek their advice.

Jack.

[ricstew]

I dont think it is Jack.......I can achieve focus at 28mm and 34mm but above that is blurry not just front or back unfortunately sometimes the motor just doesn't seem to run??
cheers
Jan

[Cage]

Keep us posted Jan.

I've had my K5 for 2 days, and almost got it sorted, 'almost' being the operative word, so I hope it's a lens gliche.

[pixy]

Jan, still contact Kennedy`s explain to them and they will sort it out, I have found them very helpful.

Jack.

ps I have a 28-70 sigma which works OK, but is soft at 2.8 on the longer focal lengths, but gets better stopped down have you tried this .

[ricktas]

Jan, still contact Kennedy`s explain to them and they will sort it out, I have found them very helpful.

Jack.

ps I have a 28-70 sigma which works OK, but is soft at 2.8 on the longer focal lengths, but gets better stopped down have you tried this .

Most lenses have a sweet spot, usually between about f8 and f14 where they are sharpest, and generally the further you go either side of the sweet spot, they become softer, so it is not uncommon to see lenses that are softer at f2.8 and f22, than mid range aperture values. Its just science.

[ricstew]

My test shot were all at f8 which showed just how blurry it could be Will ring Kennedy this arvo.....phooey
cheers
Jan

[crafty1tutu]

I had trouble with a Sigma 70-200 2.8 lens that I bought when I was in Hong Kong in 2009. It was obviously a dud as it was back with CR Kennedy 14 times in the first 12 months and back to Sigma in Japan twice (it wouldn't auto focus). In the end Sigma replaced the lens and throughout all the problems, CR Kennedy were marvellous. If you are not happy with the lens, you will just keep taking it to them until a result can be found. I have since sold it and bought the Canon version, which I probably should have waited to buy, even if it meant saving for a little longer.