Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-12-2007, 02:30 PM   #1
Veteran Member
Toshi's Avatar

Join Date: Sep 2006
Location: San Francisco, CA
Posts: 431
Aperture blades sticky?

I just got a Super-Multi-Coated Takumar 200mm f/4 lens and I tested the aperture blades by setting it to f/22 and pressing down on the pin. When I push the pin in, the hole gets smaller, and when I let go, it opens up again as it should - however, it seems like it's a bit slower than when I did this same test when I had a SMC Takumar 1.4 which opened and closed almost instantly. Is this considered sticky/oily blades? I purchased it from a seller who repairs lenses and it was stated the the blades were cleaned. Is this normal for this type of lens? Lasty, what effect will this have on taking photos and the result of the photo?

04-12-2007, 02:47 PM   #2
Senior Member




Join Date: Apr 2007
Posts: 161
I don't think it will affect the pictures, since you have to manually stop down the lens on your DS anyway. Could you post some pics taken with the lens, as I'm interested in the 200/4 Tak as well.
04-12-2007, 03:20 PM   #3
Veteran Member
FotoPete's Avatar

Join Date: Feb 2007
Location: Toronto
Photos: Gallery
Posts: 1,710
Wait first of all..is the lens still sharp. Haha. The weakest aspect of disassembly is the part where you put it back together. You gotta get all the lenses back in the right place and stuff.

Put the pin down a couple times. It may loosen up the blades. Anyhow, Mile's right. Its a screwmount lens so you have to manually stop it down anyways.
04-12-2007, 03:49 PM   #4
DAP
Senior Member




Join Date: Feb 2007
Posts: 151
It definately sounds like oily blades (a lot of times you can't see any evidence of oil on the blades, but it is there). This is due to the helicoid lube in old lenses leaching out into the aperture assembly. The proper way to fix it would be to open the aperture assembly up and clean each individual blade (remember to regrease the helicoid with a modern synthetic lube while you are in there). A stop-gap fix would be to soak the aperture assembly in solvent (lighter fluid) to dissolve the grease (after the glass is removed of course). Either way it is a pita to fix and I wouldn't accept a lens that showed this behavior (especially after it recently had this problem "fixed") if you bought it under the assumption that it was functioning normally. Try to get your money back (yeah you don't really need fully functioning blades if you are shooting in stop-down mode, but I am assuming you paid for a working lens).

04-12-2007, 05:35 PM   #5
roy
Inactive Account
roy's Avatar

Join Date: Sep 2006
Location: D/FW area, Tx.
Photos: Gallery
Posts: 1,712
QuoteOriginally posted by Mile High Quote
I don't think it will affect the pictures, since you have to manually stop down the lens on your DS anyway. Could you post some pics taken with the lens, as I'm interested in the 200/4 Tak as well.
mike,
consider a vivitar 200mm f3.5 as well. it's a real sleeper lens. sharp as a tack.
04-12-2007, 06:14 PM   #6
Veteran Member
Toshi's Avatar

Join Date: Sep 2006
Location: San Francisco, CA
Posts: 431
Original Poster
Thanks for the replies everyone,

QuoteOriginally posted by Mile High Quote
I don't think it will affect the pictures, since you have to manually stop down the lens on your DS anyway. Could you post some pics taken with the lens, as I'm interested in the 200/4 Tak as well.
I'll try and get some photos up as soon as I get home; hopefully it'll still be a little bright outside. I tried looking for reviews/photos for this lens but couldn't find any; we'll see how it performs

QuoteOriginally posted by FotoPete Quote
Wait first of all..is the lens still sharp. Haha. The weakest aspect of disassembly is the part where you put it back together. You gotta get all the lenses back in the right place and stuff.

Put the pin down a couple times. It may loosen up the blades. Anyhow, Mile's right. Its a screwmount lens so you have to manually stop it down anyways.
I just got the lens and I'm still at work, but I'll try to put up some sample photos when I get home. I pressed the pin down multiple times and it's still not as quick as the 50mm 1.4 Tak I had.

QuoteOriginally posted by DAP Quote
Either way it is a pita to fix and I wouldn't accept a lens that showed this behavior (especially after it recently had this problem "fixed") if you bought it under the assumption that it was functioning normally. Try to get your money back (yeah you don't really need fully functioning blades if you are shooting in stop-down mode, but I am assuming you paid for a working lens).
I don't think it was necessarily fixed for this problem, just cleaned and serviced by a qualified Pentax repair tech. If it doesn't pose a problem I really don't mind since I won it for only $30+. If it is indeed oily blades, can it get worse over time?
04-12-2007, 11:15 PM   #7
Veteran Member
Toshi's Avatar

Join Date: Sep 2006
Location: San Francisco, CA
Posts: 431
Original Poster
Here are some quick sample photos from the Super-Multi-Coated Takumar 200mm f/4 lens - nothing special, just a quick test of the lens. By the time I got home, the sun was nearly gone, so I didn't get much good light; anyways, a couple of street signs.





There's a bit of purple fringing (I assume) within the blurred one-way sign.



Stop sign isn't as in focus, but wanted to show the nice bokeh.

All shots were shot wide open (f/4) due to the fading light. Only post-process was a little sharpen. So far, it seems like a very good lens, especially for the price paid ($37). When testing the lens, I noticed it's pretty hard to keep the camera steady; the lens is on the heavy size, so I'm not use to it yet. Focus and aperture ring are both smooth and solid. I'll probably give it a small workout this weekend when I go out shooting with a friend.
04-13-2007, 12:02 PM   #8
Senior Member




Join Date: Mar 2007
Location: Orange County, CA
Posts: 103
Yup, it's a sharp lens!
You've got your self a great deal!

Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
aperture, aperture blades, blades, k-mount, lens, pentax lens, pin, slr lens, takumar
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Oil on aperture blades dgaies Pentax SLR Lens Discussion 2 08-10-2010 07:41 AM
Does sticky/sluggish aperture blades on an M42 lens really matter? Peter Zack Pentax SLR Lens Discussion 13 10-04-2009 09:59 PM
Sticky blades? audiobomber Pentax SLR Lens Discussion 5 11-21-2008 07:42 AM
How to fix sticky/slow blades? TimB Pentax SLR Lens Discussion 35 09-22-2008 09:01 AM
Question about aperture blades on my fa 31 ltd skawi Pentax SLR Lens Discussion 6 07-15-2008 01:25 PM



All times are GMT -7. The time now is 11:05 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top