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04-05-2014, 02:27 PM   #1
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Help needed with FA* 300 focus issues

Hi,

I recently bought an FA*300 to use for birding & general wildlife shots. I was going to use it with my 1.7x AFA. I took some test shots with this combo of some backyard birds, and none of the shots I got were in focus. I was locked down on a tripod using a Winberley Sidekick, and a cable release. I tried with both the SR on & off with similar results. I then started thinking that maybe my shutter speeds were just too slow. I remember reading here on the forum that a couple of guys were shooting handheld with this exact combo getting perfectly acceptable shots. My next thought was that it was the AFA causing the focus issues. I set up a test inside today using a focus chart at a 45 degree angle to the lens. I started with the AFA attached, and was still getting unusable shots at even f11 (corrected). I took off the AFA expecting to get completely different results, but to my surprise, the lens by itself didn't seem to perform any better. I was shooting about 20 feet away to make sure I was well past the MFD of the lens (which I understand is around 6.5 feet). I also tried coming closer to fill the frame with the test chart a little more. After all of my testing today I am at a loss & feel like this lens should be a lot sharper (even at f4.5) than it is.

I uploaded the shots I took here:

FA 300 Focus Test 040514

The shots are crops of the test chart about 9 feet away from the lens. I was shooting with a K-5ii on a tripod using a cable release & MUP, f4.5, ISO 1600, 1/640 sec, with no SR. The shots were: manual focus, AF w/ no adjustment, -10, -5, 0, +5, +10.

I really can't see a big difference here. Am I doing something completely wrong, or have forgotten something, or might there be a problem with the lens.

I appreciate any help and / or advice. Unfortunately I can't return the lens if in fact there is an issue with it. I've never had any issues with the AFA on any other lenses, and this is my first nice long lens, so I'm hoping it's my inexperience here and not a problem with the lens.

Thanks!

George


Last edited by gsrokmix; 04-29-2014 at 12:44 PM.
04-05-2014, 03:03 PM   #2
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I'm afraid it sounds very much as if the lens is faulty.
04-05-2014, 05:20 PM   #3
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Thanks, I of course hope you're wrong

I wanted to make sure I wasn't performing the test incorrectly to start.....
04-05-2014, 05:25 PM   #4
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Are the lens elements clear and clean when you look though it off camera?

If you have the F2.8 version it's probably worth getting it serviced.

BTW, the AFA works best with F2.8 or faster lenses.

04-06-2014, 09:11 AM   #5
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I have F4.5 version, purchased it second hand a while ago and absolutely love it.
if you have the same one check push-pull AF/MF ring , make sure that is properly locked in place.
04-06-2014, 01:15 PM   #6
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Yes it is the f4.5 version, sorry I forgot to mention in the OP.
04-06-2014, 02:17 PM   #7
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UPDATE: Well I did some more testing today & I'm pretty sure it's the lens. I took some more shots of the test chart, and then switched to the Tamron 90mm macro because it was handy. The results were night & day. Nice & tack sharp & contrasty wide open at f2.8. I put the 1.7x AFA on & at the corrected aperture of f4.5, still tack sharp & contrasty. The FA 300 just doesn't seem to get even reasonably sharp to me until f11.

It sucks because I bought this from KEH in EX+ condition for $999 & it's now a few months past their warranty period as I bought it in December...The few down & dirty test shots I made with it when I first got it looked good, and I haven't had time to play with it seriously until just a few days ago.....hard lesson learned there....

So now assuming it's the lens, can this be fixed? If so, who do I send it to, Eric H, or CRIS?

Thanks

George
04-06-2014, 03:17 PM   #8
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QuoteOriginally posted by gsrokmix Quote
o now assuming it's the lens, can this be fixed? If so, who do I send it to, Eric H, or CRIS?
Doesn't KEH have a 6 month warranty on all their used gear? I think they have an in house repair shop too.

04-06-2014, 05:48 PM   #9
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I have sent them an email. I think there are 6 days left on their warranty, so hopefully they can do something.
04-06-2014, 07:55 PM   #10
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I'd get them on the phone and get a commitment from them before sending it in.
04-29-2014, 12:50 PM   #11
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UPDATE #1

So Luckily I had literally a few days left on KEH's warranty. Good thing for that. They have had the lens for a few weeks now, and the salesman has told me that they can not duplicate the problem on 4 different camera bodies. I don't know if I mentioned in my OP, but the focus ring also never "stopped". It just would turn basically endlessly. I didn't think anything of this when I first got the lens for whatever reason. I have since learned that it is of course supposed to "stop" at both ends of the focus range. So today I received this email from my KEH saleman:

"Hello Mr. ******,

Your lens has been evaluated 4 different times by 4 different technicians, and unfortunately, it’s working fine on all of our cameras. We have found that from time to time, manufacturers make small changes in the electronics of their cameras and lenses, and as a result, a certain lens won’t work with a certain camera, due to the chip in the camera or in the lens. This must be the case with your lens. All I can do at this point is to either send you a different lens, or refund you for your lens. Please let me know what is the best option for you.

Thanks,

********"

Has anyone ever heard of this? Maybe with other systems but there are no chips in either the FA 300, or the K-5 ii that would be connected correct?

Either way, I'm going for the refund, which hopefully won't take forever.
04-29-2014, 01:13 PM   #12
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That lens has a push-pull MF-AF switch -- if you had it on AF it should move freely (so that you can't interfere with AF while holding it) so there's your lack of a stop. My guess is that you weren't even aware of the existence of this switch and it was somewhere in the middle the whole time messing up focus? Or you had it on MF and were interfering with the action? But I bet there is in fact nothing wrong with the lens or your camera or the combo thereof.
04-29-2014, 01:18 PM   #13
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Hey Von,

I should've been more clear with my last post. I was quite aware of the push-pull switch. The ring spun without stopping when switched to MF. I did all of my tests with the chart in both MF, & AF with the exact same results. KEH is saying that the lens is performing as it's supposed to.........I don't think so. I tested it on the camera directly, and with the 1.7x AFA. If you click on the link in my original post you'll see that all of the pix were OOF with low contrast.

Thanks!

George
04-29-2014, 01:22 PM   #14
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Hmmm...none of it makes sense really -- somebody is missing something obvious. If it were me I'd like to get it back and see for myself, but if you are up against a deadline...
04-29-2014, 01:33 PM   #15
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For anyone that's clicked the link to see the FA 300 images, here is one for comparison. It's the Tamron 90mm macro. It looks like it's front focusing a little (?) but it's night & day from the 300.

Thanks George
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