MC Helios-81N 50/2 and Nikon 50/1.8 Series E comparison

[Scheimpflug]

So I just picked up my first Russian lens, a 50/2 MC Helios-81N (гелиос-81н). It is quite dusty, so I will need to give it a good cleaning. It also has just a touch of fungus, so I haven't decided if I should leave it as-is (and try to prevent the fungus from getting worse), or take it apart to clean it. Has anyone taken an 81N apart?



I've done some searching, and have found a few other threads with samples:
http://forum.mflenses.com/helios81n-50mm-f2-samples-t5097.html
http://forum.mflenses.com/helios-81n-arrived-today-t4116.html
http://forum.mflenses.com/kirchhain-helios-81n-and-vivitar-2-0-28-t9363.html

All of these threads say good things about the lens, so I'm looking forward to using it.



While searching for information about the Helios-81N, I was finding quite a few sources claiming the Helios lens was "a Russian clone of the Nikon 50/1.8 Series E", both in terms of size and optical design. As luck would have it, I also was able to find a worn but working copy of the Nikon, a lens I have wanted for quite some time, from the same seller! It is in the same dusty condition, but no fungus that I can see.

Since I have the two here, I figured I would post a picture to dispel the myth that these are identical lenses.




As you can see, there is a considerable difference in the size of these two lenses. To be specific, the Helios measures 31mm from flange-to-filter, while the Nikon measures just 24mm. The difference seems small (just 7mm), but to put it in perspective, the Helios is 29% longer than the Nikon. It really is a noticeable difference, one that you can tell right away when you hold the two in your hands.

The Helios is also heavier, but I suspect it is also more durable. The Nikon's plastic construction is a great benefit for its weight, but also its downfall, and I have a second (broken) 50/1.8 E that bears witness to this.

[Attila]

Good friend of mine did ask me too looking somebody who has this lens, if you have it please let me to know! Many thanks in advance!

[BurstMox]

All I can say is that Helios-81 is not exactly like Helios-44

H-81:


H-44 :

(from zenitcamera.com)

[bernhardas]

Edited

[CuriousOne]

All of them are double-gauss design, derivative from Zeiss biotar

[aoleg]

I don't know who spreads rumors of these Ukraine-made lenses being clones of Nikon's, but rest assured they are not. Double-Gauss designs are prevalent for making standard (~50mm) lenses, so naturally their design is based on similar principles (as well as dozens other standard lenses).

[BurstMox]

[Drack]

I have cleaned one Helios-81N. It is quite easy. In order to remove the front element block, remove the nameplate. For the rear group I`d remove the ount and the the block should unscrew easily.