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135mm F3.4 Apo Flaring?


Ozytripper

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Hi Everyone,

I don't know if this issue has been raised before but I just bought a 135mm F3.4 Apo 6 bit coded lens and it flares quite badly. Is this normal of this lens? Could not find any reviews on the lens that addresses flare.

It does not flare when shooting directly into a light source but flares when the light source is out of the frame just like what the Tri-elmar MATE experiences.

Any feedback will be appreciated

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Any feedback will be appreciated

 

Oblique light striking the front element but outside the image area can lead to flare in some lenses. The solution as UliWer says, is simply a more effective lens hood. The 135mm has a narrow enough field of view to allow another one to be used and there are plenty available which will fit and still cause no vignetting. Its a matter of length versus sufficient shielding from oblique light - which may need some experimentation. The 75mm Summicron suffers in this way too and an additional 49mm fitting hood is on my list of items to eventually buy. The real problem is the design limitations imposed on the integrated hood which should probably be a 'double type', as fitted to some older lenses, which could be extended further in the situations that you describe. Obviously Leica haven't taken this approach so we simply have to extemporise.

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Yes, the Apo-Telyt shows some flare in situations as you describe. If this really bother you, you might try an additional shade. Heliopan and B+W offer them for the 49mm filter thread:

Thank you for the info. I presume these are screw on shade (hood) like a filter? 

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If you search ebay using up the terms 'Pentax 135 150 200' together you will find the sort of hood which should be fine - there are quite a number available. Something like this should be useful for the type of shot you describe.

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Most if not all lenses behave this way more or less. Always extend the built-in hood when you shoot against the light and if this doen'st work, you may wish to make some more shade with an accessory hood or simply with your hand as i did here:

 

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Never seen a sans flare lens so far, especially when high light sources are just outside the frame. My coded 135/3.4 apo from 2012 does pretty well in this regard but i need to use my hand or a hat in the worst cases as in the pics above. Never felt the need to purchase an additional hood but i don't use filters. 

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Thank you everyone for your response and suggestions. looks like a longer hood as suggested may be the answer. 

The original pull out hood is quite long so it is unlikely he light coming from an angle can hit the from element (especially without filter). I wonder if the light is hitting on the lower part of the hood and then being reflected back onto the lens

 

Uliwer - will see if anyone sells them locally

 

PGK - I did google your recommendation and they seem to be very reasonably priced

 

Happymac - glad your problem was resolved by Leica

 

ICT - my lens flare cannot be stopped even with my hand shading the lens. 

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ICT - my lens flare cannot be stopped even with my hand shading the lens. 

 

That surprises me - I wonder if it is worth getting Leica to check your lens in case there is some internal lack of flare prevention - such as unpainted lens element edges (can happen apparently)? Try a long hood and see if it helps - cheap enough option even if as a test - if it doesn't then I suggest that you get the lens checked.

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That surprises me - I wonder if it is worth getting Leica to check your lens in case there is some internal lack of flare prevention - such as unpainted lens element edges (can happen apparently)? Try a long hood and see if it helps - cheap enough option even if as a test - if it doesn't then I suggest that you get the lens checked.

agree with your assessment.

Will get an external lens hood first. if it doesn't work then something must be wrong with the lens

Takes great pictures when there is no flare

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The 135 APO flares light sources that are just outside the image area due to internal reflections off the inside of the lens barrel behind the rear element.

 

 

See: https://www.l-camera-forum.com/topic/245402-135mm-apo-telyt-flare/?p=2820640

 

In common with the 90 TEM "thin".

 

In theory, a longer hood would reduce this, but in reality the 135 is such a long, thin optical system that any hood that will actually shade the inside of the barrel from light will also start vignetting into the corners of the picture. I know - I tried a dozen different varieties and lengths of 49mm shades. Simple question of geometry.

 

The only solution is to avoid bright light sources in the fairly narrow band/ring of about 2 picture diagonals outside the edges of the frame. Stopping down some can sometimes reduce the amount of flare ( the aperture blades form a wall or "baffle" of their own, that internally shades the reflective area a bit.)

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I wouldn't call it the "helicoid" - it is the matte black, ridged inner tube behind the helicoid and glass, or between the rear element and the lens mount.

 

Even matte black paint and ridges will reflect light like a mirror if the angle of reflection is flat or "glancing" or "grazing" enough.

 

See: http://www.grahamoptical.com/graze.html

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The 135 APO flares light sources that are just outside the image area due to internal reflections off the inside of the lens barrel behind the rear element.

 

 

See: https://www.l-camera-forum.com/topic/245402-135mm-apo-telyt-flare/?p=2820640

 

In common with the 90 TEM "thin".

 

In theory, a longer hood would reduce this, but in reality the 135 is such a long, thin optical system that any hood that will actually shade the inside of the barrel from light will also start vignetting into the corners of the picture. I know - I tried a dozen different varieties and lengths of 49mm shades. Simple question of geometry.

 

The only solution is to avoid bright light sources in the fairly narrow band/ring of about 2 picture diagonals outside the edges of the frame. Stopping down some can sometimes reduce the amount of flare ( the aperture blades form a wall or "baffle" of their own, that internally shades the reflective area a bit.)

Thank you Andy for your explanation which I tend to agree on. Judging by the angle of the light source that causes flare I just cannot see light striking the front element.

 

I could not find a Pentax 135 150 200 mm lens hood locally but managed to track down an old 49mm no brand 60mm long hood. Built like a tank

Seems to help a bit indoors but I really have to test it outside to see if it really helps  

Will post the outcome 

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What the 135 APO really needs is the addition - by Leica - of a rear baffle with a rectangular cutout to "crop" the incoming light to only that light needed for the rectangular image area.

 

Many "lesser" manufacturers do this for extra flare control, and have for decades (1960s Micro-Nikkor extension tube, e.g.)

 

http://www.savazzi.net/photography/images/m_ring.JPG

 

https://www.pentaxforums.com/content/uploads/files/77/1282/IMG_2001sw2000_atx.jpg

 

Of course, you can "roll your own" with some black tape around/across the rear lens opening (avoid the moving RF cam, though)

 

http://bophoto.typepad.com/.a/6a00e553e3747888330105365f61a7970b-pi

 

Most lenses (and most M lenses) don't need this - it is just the handful of Leica teles with a really long empty barrel segments behind the rear element that could do with the extra help.

 

or the Rolleiflex with its deep film chamber behind the rear element - later Rolleis employed 2-3 baffles to kill reflections off the sides/top/bottom of the film chamber:

 

http://farm2.static.flickr.com/1682/24820159896_e79f2c2f4e.jpg

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Hi Guys,

bough this hood. 49mm by 60mm long. Took the lens for a test drive tonight and there was a significant improvement. Still some flare but is now bearable:

-flare is only very slight and restricted to the edges of the picture (previously was 2/3rds of the whole picture) 

-slight change in angle removes the flare (previously unavoidable)

-happens only rarely

thanks for the suggestions and actual solution

 

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