Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-02-2016, 03:12 PM   #1
Otis Memorial Pentaxian
Loyal Site Supporter
photolady95's Avatar

Join Date: May 2009
Location: Cruising the forum watching his back
Photos: Gallery | Albums
Posts: 12,621
Anyone ever done this before?

I have an older Sigma lens whose rear element went foggy, unable to clean it because it's plastic. Now I have two other Sigma lenses and was thinking since the older lens was particularly sharper at 300mm than the other two, I could take the rear element from one of my other lenses and swap them out. All are Sigma 70-300mm Macro lenses. The older one is an APO model though and the other two, neither is APO nor DG models. All three are AF lenses with same f stops. Would it work?

06-02-2016, 03:28 PM   #2
Senior Member




Join Date: Jun 2015
Photos: Albums
Posts: 235
I haven't done that with those lenses before, but I have swapped rear elements on cheap primes before and it can change stuff alot. I would go for it and see what happens. A fun experiment!
06-02-2016, 03:31 PM   #3
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 49,596
QuoteOriginally posted by photolady95 Quote
I have an older Sigma lens whose rear element went foggy, unable to clean it because it's plastic. Now I have two other Sigma lenses and was thinking since the older lens was particularly sharper at 300mm than the other two, I could take the rear element from one of my other lenses and swap them out. All are Sigma 70-300mm Macro lenses. The older one is an APO model though and the other two, neither is APO nor DG models. All three are AF lenses with same f stops. Would it work?
Assuming the lenses don't break during disassembly, I think the APO version has different optics than the earlier lenses, so probably won't work.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

06-02-2016, 04:19 PM   #4
Otis Memorial Pentaxian
Loyal Site Supporter
photolady95's Avatar

Join Date: May 2009
Location: Cruising the forum watching his back
Photos: Gallery | Albums
Posts: 12,621
Original Poster
QuoteOriginally posted by Adam Quote
I think the APO version has different optics than the earlier lenses, so probably won't work.
Thanks for your input Adam. I'm not too worried about breaking them. The APO version has already been disassembled, me trying to clean the rear element and I didn't break it.

QuoteOriginally posted by kmurphy220 Quote
I haven't done that with those lenses before, but I have swapped rear elements on cheap primes before and it can change stuff alot. I would go for it and see what happens. A fun experiment!
I guess I'm just going to try it.
I'm a computer tech too so I know how to be careful with disassembling equipment and reassembling them.

06-02-2016, 05:16 PM   #5
Site Supporter
Site Supporter
DeepThrob's Avatar

Join Date: Nov 2012
Location: Taos, New Mexico
Posts: 240
'plastic rear element' ?
06-02-2016, 07:45 PM   #6
Otis Memorial Pentaxian
Loyal Site Supporter
photolady95's Avatar

Join Date: May 2009
Location: Cruising the forum watching his back
Photos: Gallery | Albums
Posts: 12,621
Original Poster
QuoteOriginally posted by DeepThrob Quote
plastic rear element' ?
Yes. I was surprised to learn that when I disassembled it to try and clean it.

Last edited by photolady95; 06-02-2016 at 08:31 PM.
06-02-2016, 10:33 PM   #7
Site Supporter
Site Supporter




Join Date: May 2016
Photos: Albums
Posts: 1,488
QuoteOriginally posted by photolady95 Quote
Yes. I was surprised to learn that when I disassembled it to try and clean it.
There isn't a plastic cleaner you can use to clean it? I was speaking to a framer the other day, and they mentioned that you can't use glass cleaner (Windex) on plexiglas (used instead of glass when framing large photos), but there is something else intended for cleaning plastic. Maybe that type of thing would be possible here? I mean, it may be worth a try, if your only other alternative seems to be what you are suggesting.

Lee
06-02-2016, 11:02 PM   #8
Otis Memorial Pentaxian
Loyal Site Supporter
photolady95's Avatar

Join Date: May 2009
Location: Cruising the forum watching his back
Photos: Gallery | Albums
Posts: 12,621
Original Poster
I searched for plastic cleaner and found nothing suitable for cleaning the type of plastic in the rear element. Especially when I didn't know what type of plastic it was, I was unsure of what to get.

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!
apo, element, k-mount, lens, lenses, pentax lens, sigma, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Has anyone seen this haze on glass before? thehabit Pentax SLR Lens Discussion 9 06-27-2015 05:49 AM
Has this ever happened to anyone else? wile Pentax K-5 6 12-07-2014 04:21 PM
Shooting with two 645s - has anyone done this before? dugrant153 Pentax Medium Format 12 08-30-2011 10:15 PM
Has anyone done real estate photography before? jennverr Photographic Technique 19 02-02-2011 07:17 AM
Anyone know how this is done? rwheeler Photographic Technique 10 11-20-2009 02:41 AM



All times are GMT -7. The time now is 11:56 PM. | See also: NikonForums.com, CanonForums.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