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04-02-2011, 01:10 PM   #1
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8 Element Takumar 50/1.4:

I recently was pleased to obtain an old 8 element Takumar and was surprised to find that even using a lens hood at small apertures (f8, f11 and f16) I obtain purple colored lens flare in the centre (the shape of the aperture). Larger apertures seem to be OK. If the sun was due east I would be pointing the lens due north.

I also have the non SMC super takumar 50/1.4 (7 element) which tested side by side - even without a lens hood - does not produce this flare?

Camera is K10D, no filter used on either lens

Thanks for any advice out there?

04-02-2011, 01:17 PM   #2
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What are your in-camera processing settings?

Have you shot with all of your options zeroed out?
04-02-2011, 01:21 PM   #3
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I shoot raw - if that is what you mean - and using Av.

Remember that a side by side test with the other lens (same conditions otherwise) does not produce this problem.

Last edited by stevewig; 04-02-2011 at 01:30 PM.
04-02-2011, 01:33 PM   #4
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Wow--and okay.

It has to be a coating issue then, since I never heard of this issue with this lens--which is "supposed" to blow away the standard S-Tak 50 1.4 which you and I both own.

Does that lens have the radioactive coating like the later ones did, and did you ever process it (steady exposure to sunlight or UV light) to neutralize the yellowing common in the older lenses?

Just throwing some ideas out there. I know the yellowing is a separate issue, but who the hell knows. Maybe doing the same treatment will help.

04-02-2011, 01:56 PM   #5
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QuoteOriginally posted by Ira Quote
Does that lens have the radioactive coating like the later ones did, and did you ever process it (steady exposure to sunlight or UV light) to neutralize the yellowing common in the older lenses?
No. The 8-element Tak is not Thoriated. No yellowing.

The pics in this set were taken with the 8-element Tak. I didn't notice any flare in the outdoor pics.

Wings of Eagles - Elmira-Corning Regional Airport - a set on Flickr

Better versions

A-26 Take 2 - a set on Flickr
04-02-2011, 02:25 PM   #6
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Does the lens have a flat rear element? If so its light reflecting off the sensor onto the rear element, then back onto sensor. Its also present at wider apertures, but the reflection becomes large enoogh to cover the whole frame. The adaptall 2 SP 90mm nacro has the same problem.

Edit: Just checked the lens diagram, sure enough, it has a flat rear element. The 7 element versions have a curved rear element.
04-02-2011, 02:44 PM   #7
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QuoteOriginally posted by selar Quote
Edit: Just checked the lens diagram, sure enough, it has a flat rear element. The 7 element versions have a curved rear element.
Nope. Other way around.

04-02-2011, 03:34 PM   #8
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OK

I just checked ny 8 element Tak 50.

First of all, I have verified this is the 8 element based not only on protruding rear element, but also the focus mark, serial number and weight of the lens. Let's all just assume here this is a true 8 element version.

I went out, to push the lens to the extremes. I have the origonal Takumar 50F1.4 lens hood for this lens, not just any hood.

If I shoot into the sun, lens stopped down, with the sun just beyond the corner of the lens, I get a good amount of flare stopped down, with a clear purple patch in the middle of the image

with the sun at almost angles, and stopped down all the way, It may be possible that there is some small purple in the middle of the image also, but no other flare.

With the sun behind you , or in the shade, there is no issue. It is probable this is internal reflection in the lens. and I will need to do more tests.

Just for the record, my lens has a SMC skylight filter on it.

edit note

the lens performe a whole lot better with the much longer hood of the 135F3.5 attached, and no apparent vignetting.

Still, however, I can see when shooting into the light even when no noticible flare, a little purple tinge or shading to shots, shen stopped right down.

Second edit note, First tests on my *istD, still there but less obvious on my K10D

Last edited by Lowell Goudge; 04-02-2011 at 03:59 PM.
04-02-2011, 04:31 PM   #9
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QuoteOriginally posted by Lowell Goudge Quote
OK

I just checked ny 8 element Tak 50.

First of all, I have verified this is the 8 element based not only on protruding rear element, but also the focus mark, serial number and weight of the lens. Let's all just assume here this is a true 8 element version.

I went out, to push the lens to the extremes. I have the origonal Takumar 50F1.4 lens hood for this lens, not just any hood.

If I shoot into the sun, lens stopped down, with the sun just beyond the corner of the lens, I get a good amount of flare stopped down, with a clear purple patch in the middle of the image

with the sun at almost angles, and stopped down all the way, It may be possible that there is some small purple in the middle of the image also, but no other flare.

With the sun behind you , or in the shade, there is no issue. It is probable this is internal reflection in the lens. and I will need to do more tests.

Just for the record, my lens has a SMC skylight filter on it.

edit note

the lens performe a whole lot better with the much longer hood of the 135F3.5 attached, and no apparent vignetting.

Still, however, I can see when shooting into the light even when no noticible flare, a little purple tinge or shading to shots, shen stopped right down.

Second edit note, First tests on my *istD, still there but less obvious on my K10D
Thanks everyone for your help.

Lowell - I appreciate your effort there very much!

My lens has the curved rear surface, has the red index to the right of the f4 (when viewed from behind the camera) and has S/N 1314318 so I am sure that it is the 8 element.

Looks like you pretty well reproduced my results!
(I believe that any attempt to use a filter of any description will only make matters worst?)

I also have the genuine 135/3.5 hood and I will try that tomorrow.

Lowell have you ever done any sharpness testing between the 8 element and the 'Super Multi Coated' version? I believe that the only difference is "character"?
04-02-2011, 05:42 PM   #10
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I don't have any other Tak 50. But I do have the K50/1.4 and m50/1.7 and M50/2 that I could try
04-02-2011, 06:42 PM   #11
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QuoteOriginally posted by Lowell Goudge Quote
the lens performe a whole lot better with the much longer hood of the 135F3.5 attached, and no apparent vignetting.
Sounds like using a hood will make things better. stevewig, why not try a hood with your copy?
04-03-2011, 07:14 AM   #12
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QuoteOriginally posted by Laurentiu Cristofor Quote
Sounds like using a hood will make things better. stevewig, why not try a hood with your copy?
Thanks for taking the time to reply Laurentiu, but you missed the fact that I was using a lens hood (in the original question).

I shall be trying again using a longer hood.
04-03-2011, 07:25 AM   #13
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I went out today with my 8 element and played with internal lens flare

With no hood you can see rainbows in the viewfinder with the sun at about 70 degrees off axis. These are also visible in the shot and you can remove them using your hand as a shade. My conclusion is the super tak coatings limit outdoor shooting to cloudy days or the sun at your back

I have noticed some flare also when doing night shots
04-03-2011, 07:35 AM   #14
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QuoteOriginally posted by Laurentiu Cristofor Quote
Sounds like using a hood will make things better. stevewig, why not try a hood with your copy?
Just carried out a test using the 135f3.5 hood - no difference. Purple flare, aperture shaped at f8 and smaller.

F5.6 and wider no problem!
04-03-2011, 08:17 AM   #15
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QuoteOriginally posted by Lowell Goudge Quote
Just for the record, my lens has a SMC skylight filter on it.
Is it possible that flat surface of the filter is doing that, in one occasion my FA50 with filter did that, but with out filter or a curved filter (Pentax ghostless) did not reproduce that.

QuoteOriginally posted by stevewig Quote
I obtain purple colored lens flare in the centre
Did you also have filter on the 8E ST50?
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