OM to EOS to Mitakon Zhongyi: Vivitar vs OM

cgustav · Joined: 01 Jun 2014 Posts: 270 Location: Los Angeles

Hi there,

I'm using Olympus lenses with the Mitakon Lens Turbo ii and so far I'm pretty happy with the combo.
If I want to be picky, the only thing that's a little annoying is the moment I've to mount the lens. I've tried several OM to EOS adapters without significant improvement.
Basically, sometimes it seems the lens doesn't fit, but after trying over and over, eventually, it snaps to the Mitakon.
I'm thinking the reason for this, is because of this part of the lens:

That said, everything else works fine.

Now the confusing part of the story.
I've recently bought a Vivitar 28 2.8 OM mount.
At first, I was happy to notice that unlike my other Zuiko lenses, the Vivitar was mounting on the Mitakon like a glove.
But then I noticed that, after the lens snaps, there's a tiny, little movement I can do, moving the lens back and forth.
It is small, but that small movement can affect the light that enters the lens.
Is not preventing me from using the lens, as the small difference in terms of aperture is still OK, but it is definitely annoying as I like to think the lens snapped tightly.
The Vivitar doesn't have that rear protrusion which makes me think is the reason why it doesn't snap tight.

Is there a way to make the Vivitar mounting tighter?

kansalliskalaCafe · Posted: Mon Jul 31, 2017 8:30 am Post subject:

is that 28/3.5 G.Zuiko? all OM lenses don't have that part at all (which is something for preventing reflections or so ..)

cgustav · Joined: 01 Jun 2014 Posts: 270 Location: Los Angeles

My 35 2.8, 28 3.5 and 24 2.8 they all have the same rear. I think my 50 1.4 has it too, I don't remember if my 100 2.8 has it.
But the problem are not the OM lenses.
What I'm trying to figure out is what to do with the Vivitar.

dnas · Joined: 14 Nov 2008 Posts: 488 Location: Japan

On the shorter focal length OM Zuiko lenses, the protruding part is to protect the rear glass element. Are sure that if you remove it, put a mount cap on to protect it.

cgustav · Joined: 01 Jun 2014 Posts: 270 Location: Los Angeles

dnas,

Like I said, the problem is not with the OM lenses.

What I'm trying to figure out is how to mount the Vivitar tight.

dan_ · Expire: 2016-12-19

Thé same problem was solved here:
http://forum.mflenses.com/odd-nikon-mount-problem-t77717,start,25.html

cgustav · Joined: 01 Jun 2014 Posts: 270 Location: Los Angeles

dan_ · Expire: 2016-12-19

You are welcome.
No, don't unscrew anything. Put the screwdriver exactly like in the photo in the little slit inside the mount end enlarge the slit a little (all the similar slits around the mount).
That slits are made for this purpose.

cgustav · Joined: 01 Jun 2014 Posts: 270 Location: Los Angeles

dan_,

I'm not sure that fixes it. Isn't that supposed to tighten the lens to the adapter?
My problem is not between the lens and the 1st adapter, i.e. OM to EOS, but from the 1st adapter to the Mitakon.
I worked on the slits and the lens fits tight on the EOS adapter, but the problem remains when I mount the lens+EOS adapter to the Mitakon which doesn't happen with any of the Olympus lenses.