Pentacon 135mm f/2.8 Aperture Blades Repair

In depth video of how to repair the aperture of a Pentacon 135mm f/2.8 vintage lens. Bonus: how to declick a Pentacon 135mm f/2.8 for cinemod video use. See the chapters on the timeline of the video.
0:00 Intro
0:46 Tools
1:46 Disassembly
5:11 Extracting the blade mechanism
7:37 Taking out the blades
11:56 How do the blades work?
15:24 Cleaning of the blades
17:10 Putting back the blades
23:54 Putting back the blade control ring
27:45 Reassemble the blade mechanism
31:37 Reassemble the lens
35:38 BONUS: how to declick
36:20 How does the aperture ring work?
40:08 Final assembly
The Pentacon auto 135mm f2.8 lens is a surprisingly good telephoto lens that was build by Pentacon in the GDR. It’s a solid all metal construction and it performs superbly for a lens in its price range. The Pentacon auto 135mm 2.8 lens can be soft when shot open at f2.8 but performs much better when stopped down. The bokeh is amazing for a lens in that price range.
More detailed video of the disassembly and cleaning/greasing of the focus mechanism: • Pentacon auto 2.8/135 ...

[@luki753]

Thank you Sir! I just repaired mine with your instructions, straight forward, no problems.

[@esther_on_fire]

Thank you so much for this! I was able to get mine repaired by following this. Phenomenal video.

[@Blizzardmane]

Thank you so much this really helped with the aperture the assembly for the pentacon 50mm 1.8!!

[@fokkegorter2754]

Dankjewel! de mijne is nu ook weer als nieuw!

[@lepekmaniak]

I just bought Pentacon 135 f/2.8 electric(as my first vintage m42 lens) and unfortunately aperture didn't work and found your video. I'm not a tech guy, but I followed your video step by step and now it works perfect! Thank you!

[@adonuff3338]

Thank You that was very useful. Please make more

[@Gobzon]

Thank you very much for detailed walkthrough!
I thought I'd just click to the needed stage, but ended up watching the whole thing. Not a second of boredom :D

[@DominikMarczuk]

More videos like this, please, or else I'll need to start my own lens repair channel!

[@metehantanriverdi01]

I fixed the aperture with your help. Thank you so much.

[@nuryunianto]

Thanks your chabnel so hopefull guys

[@Fr33r1der24]

thank you

[@ohjajohh]

Super bedankt voor deze uitleg!

[@jean-marcschwartz2525]

Thank you, very useful. 👌

[@teresamarie3718]

Thank you! I just received the 15 blade version after a slightly risky but bargain blind on line purchase. It is working and clean but seems like a couple of the blades have fallen out of position. Hopefully they are not bent or damaged beyond repair. This has given me the confidence to open it up and find out 👍

[@C.I...]

How did it go? I'm in a position to buy one with a sticky aperture for a good price right now.

[@BeatboxHungary]

I did everything here... but when I zoom close (1.7m) the aperture blades cannot close beyond 5.6... when I zoom back out, i can close down to f22 without problem. I have no idea what goes wrong. The lever touches the pin of the aperture control ring on the whole spectrum, but somehow it not pushes it enough when I zoom close... anyone else with this problem?

[@sorrynotcyborg]

I'm not experienced with lens repair so when I was cleaning the inside elements all the blades came out! hahaha now i dont remember what order they were in to put them back properly. at least it was a cheap vintage Tokina 28mm.

[@thevintagelenschannel5379]

Maybe you could figure that out via this video. Basically, all aperture blade sets work the same. Put one on top of another one and find out if that would make sense if they move inwards and outwards. Best of luck!

[@LeonardoCB]

wow, Geweldige video! ik ben zelf mijn "huiswerk" aan het doen om mijn Makinon 135mm F2.8 Macro te repareren.
de Diafragma bladen die gaan niet soepel, en zou ze dus moeten poetsen.
weet je wellicht of deze lens bepaalde valkuilen heeft waar ik voor moet oppassen? sinds dat het de Macro variant is heeft hij nog een extra gedeelte dat je kan uitschuiven.
en waarmee kan ik de lens wrench vervangen? ik heb deze niet even liggen en verwacht ook niet vaker een reparatie te gaan doen.

[@HibikiKano]

How similar is the pentacon 135mm to Carl Zeis Jena 130mm ? At least the body looks very similar from the outside.
I have a perfectly smooth and clean and clear CZJ 135mm but whose Aperture got stuck open.

[@abdulkadirtosun2154]

Are you the Media divison guy? 😁

[@LaPureDick]

Y para el que es montura Pentacon B / Praktica PB, cómo desmonto la montura? 😢 la quiero cambiar por otra montura ya que no tengo adaptador para esa montura ☹️