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Old Feb 8, 2007, 12:16 AM   #1
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I hate it when I type a whole message with background and extra information, and then have my internet connection go out on me, and I have to start over. Probably for the best, my last post was (as usual) a little long winded.

My situation is this - I have a Kiron 80-200 lens that had been my fathers. I never liked it because it seemed so soft when I compared it with a Pentax F 70-210 lens I used to own. Several months ago I noticed that the lens wouldn't stop down - I had never noticed that there was oil on the aperture blades. I played with it a bit and the lens will now reluctantly stop down, so today I spent lunch taking pictures with it and the DA 50-200, using both the K100 and the K10.

I found out that the K10 doesn't meter very well when the lens is stopped down. The K100 did a bit better when using f8 and f11, but was as hopeless at f22. Don't know if that's the nature of manual lenses (my other M lenses are fast primes and I never use them smaller than f4) or reflects the poor condition of the Kiron (doesn't always stop down completely, and always does it slowly).

I also found out that the Kiron at f8 (shot raw and the overexposure problem wasn't too much for ACR to correct) was sharper than the DA 50-200 at f8 and f11 (still wonder if there isn't something wrong with my DA lens but can't figure out how to tell).

I talked to my local camera shop who quoted me $70 to get it fixed. That's probably more than what I could get for the lens (figured $50 or maybe $60 at the most), the reason why I haven't done anything about it. However, since it is sharper than the DA lens, I'm tempted to get it fixed and use it until the new Pentax * lenses come out. I can deal with the overexposure problem if it isn't a lens problem (I'll take one of my fast primes to work and see if the cameras do the same thing tomorrow). I'd be trading in AF and AE in on a manual lens that is bigger, heavier, and focuses the wrong way just to get sharper pictures (it was so grey today and I didn't work at sorting out the exposure situation enough to evaluate color rendition).

If you were in this situation, would you spend the money to get the Kiron fixed?
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Old Feb 8, 2007, 8:56 AM   #2
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if i had the DA 50-200mm I'd use that one for the 200mm range.

the small amount of sharpness it loses against the Kiron can probably be corrected in post processing, and you have all the advantages of a small, automatic lens, with a broader zoom range.

I'd keep it as a backup. Wouldn't get it fixed for 70$, as you could probably find a new one on ebay for less than that price.

The problem with the lens is probably that the camera stops it down too slow when taking the shot, thus overexposing it.

Maybe it's something that cna be fixed by playing with the lever a couple of times. Set the lens to f22 and push the lever on the back of the lens a few times. Maybe it'll go faster when after moving it around a few times...
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Old Feb 8, 2007, 6:11 PM   #3
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Played a bit more at lunch today, but ran out of time to do all that I wanted. I found out that the K10 has no problem metering with the M24mm 2.8 at any aperture, so the problem is definitely lens-caused (no sign at all of an over-exposure problem, thank heavens!). When I played with the lever on the lens a bit I discovered that it is only stopping down to about f8, no matter what the lens is set for. At f11, thelens doesn't stop down as fast as it does at f5.6 (as well as not stopping down all the way), so that's probably why I'm getting such consistently overexposed pictures - the green buttonmust stop the lens down longer than a normal shutter speed. Tonight I'll see what the pictures look like that are properly exposed, and if they are significantly better than with the DA lens I probably will get it fixed. I won't fix it to sell because its not worth it, but it might be worth fixing for my own use, if the pictures are better. I rather like the push-pull zoom.

Still haven't made up my mind.
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Old Feb 8, 2007, 8:36 PM   #4
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If you have a sticky aperture, you will never get it to work perfectly unless you either clean it yourself or have it done. It will close too slowly to meter properly and you will be getting a meter reading on its way closed and not where you have it set.

You can still use it if you take the lever on the base of the lens that stops it down when you push the shutter release and lock it in the closed position. That way the lens will become a manual lens and you can meter properly with your DSLR's. It will then stop down as you move the aperture ring and stay there.

Tom


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Old Feb 8, 2007, 9:29 PM   #5
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the kiron you have is a very sharp lens but you can replace it from ebay for quite less than 70usd
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