Decentered Takumar lens

**hjoseph7** · 11-24-2015, 09:27 AM

Is there any way to fix a decentered Takumar lens ?

bertwert · 11-24-2015, 09:31 AM

Not sure, but a little late to return it to the store...

manntax · 11-24-2015, 09:34 AM

From what I know it is pretty difficult to decenter any takumar lens simple because of tight tolerances and full metal body and internal parts. whole optical groups are usually inside their sockets and c annot be positioned differently. Perhaps your copy suffers from a loose retaining ring or not tightened fully optical assembly somewhere inside? Some decentering can also be caused by the optical elements being rotated, where the sharpness plane is not square but optimized for 35mm horizontally oriented frame of film. It will probably take some know-how and loads of patience to center lens today with no access to the specialized equipment that Asahi was using back in their day...

**hjoseph7** · 11-24-2015, 09:39 AM

I'm not sure it the lens is really decentered or if its something else, but I can see a distinct blur on the left side of the lens.

manntax · 11-24-2015, 10:09 AM

Originally posted by hjoseph7

I'm not sure it the lens is really decentered or if its something else, but I can see a distinct blur on the left side of the lens.

Maybe it suffered a knock or two before you got it and now the whole focusing assembly doesn't move with both front and rear optical groups perfectly paralleled ? I there any evidence of impact or a shock it might have suffered ? Also is there anything loose or rattling when you shake the lens - try and shake it in various directions.

**hjoseph7** · 11-24-2015, 10:26 AM

Originally posted by manntax

Maybe it suffered a knock or two before you got it and now the whole focusing assembly doesn't move with both front and rear optical groups perfectly paralleled ? I there any evidence of impact or a shock it might have suffered ? Also is there anything loose or rattling when you shake the lens - try and shake it in various directions.

No the lens looks like it's in very good condition.

dsmithhfx · 11-24-2015, 11:10 AM

Originally posted by hjoseph7

No the lens looks like it's in very good condition.

Does the glass look clean all the way through, when you look at a light source through it off-camera (try it from both ends)? Fungus can cause that kind of blurring. Can you post some examples?

manntax · 11-24-2015, 12:36 PM

Originally posted by hjoseph7

No the lens looks like it's in very good condition.

What lens we talking about - can you show some photos of it and also some sample shots taken with it ?

**hjoseph7** · 11-24-2015, 01:31 PM

Right now I don't have access to all of my images taken with this lens. I do have one image that shows traces of the blurring and this is after I applied a ton of sharpening to it. The lens is a Takumar 24mm f3.5. Notice the bricks on the church how they fade in and out and the funky flares around the lights ?

dsmithhfx · 11-24-2015, 02:20 PM

You're not giving much to go on here. What camera body was used? I don't know what decentering is supposed to look like (I never even heard of it until now), you say there is blurring on 'one side' but I see at least 2, maybe 3 distinct large blurry patches arrayed around the center of the shot. It looks a lot like some kind of grease smear, really bad fingerprinting and/or anti-reflection coating damaged by a solvent or over-zealous cleaning IMO. I suppose it could also be big drops of [rain?] water?

**hjoseph7** · 11-24-2015, 04:41 PM

If it's only grease or fingerprints that would be great ! I'm going to try cleaning the lens again then take it out tomorrow when the sun is out.

jkomp316 · 11-24-2015, 04:51 PM

does the lens exhibit this on all pictures?

wombat2go · 11-24-2015, 05:16 PM

Originally posted by hjoseph7

The lens is a Takumar 24mm f3.5. Notice the bricks on the church how they fade in and out and the funky flares around the lights ?

Yes, I think that lens has some other problem.
Maybe pf member dcshooter will come on, or you can pm him.

**hjoseph7** · 11-24-2015, 07:27 PM

Here is another one. Notice the blurry tree to your far right and that blurry patch of grass a little passed the foreground.

I just finished cleaning the back lens which did look a little dinky, then took several shots indoors and all the pictures came out OK. I want to see how it performs outdoor, that's the real test.

Reed · 11-25-2015, 12:02 AM

You probably got lens that someone was trying to clean inside and failed, looks like fingerprint grease on last or one before the last lens in the barrel- well only way to get it is to dissasembly the lens and then clean it with right cleaner(ipa for example), and get it into working order again. And that smuge appears to be big in the picture-on the lens it is probably around 2mm wide or less...

11-24-2015, 09:27 AM	#1
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048	Decentered Takumar lens Is there any way to fix a decentered Takumar lens ?

11-24-2015, 01:31 PM	#9
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048 Original Poster	Right now I don't have access to all of my images taken with this lens. I do have one image that shows traces of the blurring and this is after I applied a ton of sharpening to it. The lens is a Takumar 24mm f3.5. Notice the bricks on the church how they fade in and out and the funky flares around the lights ? Attached Images

11-24-2015, 07:27 PM	#14
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048 Original Poster	Here is another one. Notice the blurry tree to your far right and that blurry patch of grass a little passed the foreground. I just finished cleaning the back lens which did look a little dinky, then took several shots indoors and all the pictures came out OK. I want to see how it performs outdoor, that's the real test. Attached Images Last edited by hjoseph7; 11-24-2015 at 07:33 PM.

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11-24-2015, 09:31 AM	#2
bertwert Veteran Member Join Date: Jun 2015 Location: Golden, BC Posts: 15,172	Not sure, but a little late to return it to the store...

11-24-2015, 09:34 AM	#3
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	From what I know it is pretty difficult to decenter any takumar lens simple because of tight tolerances and full metal body and internal parts. whole optical groups are usually inside their sockets and c annot be positioned differently. Perhaps your copy suffers from a loose retaining ring or not tightened fully optical assembly somewhere inside? Some decentering can also be caused by the optical elements being rotated, where the sharpness plane is not square but optimized for 35mm horizontally oriented frame of film. It will probably take some know-how and loads of patience to center lens today with no access to the specialized equipment that Asahi was using back in their day...

11-24-2015, 09:39 AM	#4
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048 Original Poster	I'm not sure it the lens is really decentered or if its something else, but I can see a distinct blur on the left side of the lens.

11-24-2015, 10:09 AM	#5
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	Originally posted by hjoseph7 I'm not sure it the lens is really decentered or if its something else, but I can see a distinct blur on the left side of the lens. Maybe it suffered a knock or two before you got it and now the whole focusing assembly doesn't move with both front and rear optical groups perfectly paralleled ? I there any evidence of impact or a shock it might have suffered ? Also is there anything loose or rattling when you shake the lens - try and shake it in various directions.

11-24-2015, 10:26 AM	#6
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048 Original Poster	Originally posted by manntax Maybe it suffered a knock or two before you got it and now the whole focusing assembly doesn't move with both front and rear optical groups perfectly paralleled ? I there any evidence of impact or a shock it might have suffered ? Also is there anything loose or rattling when you shake the lens - try and shake it in various directions. No the lens looks like it's in very good condition.

11-24-2015, 11:10 AM	#7
dsmithhfx Pentaxian Join Date: Sep 2015 Location: Toronto Posts: 5,153	Originally posted by hjoseph7 No the lens looks like it's in very good condition. Does the glass look clean all the way through, when you look at a light source through it off-camera (try it from both ends)? Fungus can cause that kind of blurring. Can you post some examples?

11-24-2015, 12:36 PM	#8
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	Originally posted by hjoseph7 No the lens looks like it's in very good condition. What lens we talking about - can you show some photos of it and also some sample shots taken with it ?

11-24-2015, 02:20 PM	#10
dsmithhfx Pentaxian Join Date: Sep 2015 Location: Toronto Posts: 5,153	You're not giving much to go on here. What camera body was used? I don't know what decentering is supposed to look like (I never even heard of it until now), you say there is blurring on 'one side' but I see at least 2, maybe 3 distinct large blurry patches arrayed around the center of the shot. It looks a lot like some kind of grease smear, really bad fingerprinting and/or anti-reflection coating damaged by a solvent or over-zealous cleaning IMO. I suppose it could also be big drops of [rain?] water?

11-24-2015, 04:41 PM	#11
hjoseph7 Site Supporter Join Date: May 2014 Location: Minnesota Photos: Gallery \| Albums Posts: 2,048 Original Poster	If it's only grease or fingerprints that would be great ! I'm going to try cleaning the lens again then take it out tomorrow when the sun is out.

11-24-2015, 04:51 PM	#12
jkomp316 Senior Member Join Date: Feb 2013 Photos: Gallery \| Albums Posts: 227	does the lens exhibit this on all pictures?

11-24-2015, 05:16 PM	#13
wombat2go Veteran Member Join Date: Jan 2010 Location: Michigan Photos: Gallery Posts: 2,207	Originally posted by hjoseph7 The lens is a Takumar 24mm f3.5. Notice the bricks on the church how they fade in and out and the funky flares around the lights ? Yes, I think that lens has some other problem. Maybe pf member dcshooter will come on, or you can pm him.

11-25-2015, 12:02 AM	#15
Reed Pentaxian Join Date: Mar 2015 Location: Warsaw Photos: Gallery Posts: 638	You probably got lens that someone was trying to clean inside and failed, looks like fingerprint grease on last or one before the last lens in the barrel- well only way to get it is to dissasembly the lens and then clean it with right cleaner(ipa for example), and get it into working order again. And that smuge appears to be big in the picture-on the lens it is probably around 2mm wide or less...