Nikon Mount - Shifty Lens Play?

[Sanjin Jukic]

This is amazing, I don't know why I'm half-discovering this now,



Sanjin, do you know when they are going to release this? Looks like an awesome investment

Very soon.

Stay tuned.

 

[Martin Weiss]

Birger soon or proper soon ?

If I have say 7 Contax and 2 PL lenses, do I then need 2 or 9 adapters?

 

[Sanjin Jukic]

Just 2 adapters and PST IMS.

Or Zeiss-Contax and PL to PST IMS.

 

[C.H.Haskell]

Can you folks point me to a thread that reviews the RED nikon mount with pics...no having luck at the moment.

 

[Evin Grant]

Sanjin, how does one collimate the IMS mount?

 

[Sanjin Jukic]

Sanjin, how does one collimate the IMS mount?

Still is not clear and remains unknown.

I asked and they wrote me that each user will get "an instruction how to assemble the IMS front to your camera on your own".

That should conclude somehow that the mount is already "the PST factory collimated".

So if I can understand this message well it means that each lens should be collimated before by any standard collimator.

But all that I will leave open till I get a final report in a couple of days.

 

[Steve Sherrick]

Two things:

1. It has been mentioned by Jarred that this mount will void the warranty. So unless that has changed or will change, you need to be aware of that.

2. I would think that if you are going to do the installation yourself, this would probably for sure void the warranty.

Having said that, I have not heard whether the Birger mount voids the warranty, and certainly the Nikon mount doesn't, so maybe there will be some changes in policy at some point.

I love the idea of a universal mount as long as each mounting system works as well as it would in its native form. Looking forward to hearing more about it.

I'll post my Nikon mount video in a little bit.

 

[Steve Sherrick]

Here's the link to the video.

http://gallery.mac.com/stevesherrick#100000

 

[Evin Grant]

Here's the deal guys. The mount in the Red Nikon Mount is actually a spare part from Nikon (I'm pretty sure). It was originally designed for an extension tube and thus was made to be as thin as possible. This enables it to replace the PL mount without removing the self collimating feature. Because of the thinness of the mount it cannot be as secure as a proper SLR mount, this in a trade off and not a design flaw. Hopefully the Birger will be more secure seeing as it has to replace the whole lens mount assembly.

 

[Steve Sherrick]

And it really doesn't affect image at all, and the lens isn't going to fall out. I figured it was due to the way it is integrated with the PL mount.

 

[Jarred Land]

We need to actually see the Birger mount before we can comment on the warranty implications.

Evin's statement is false.. and didnt come from the manufacturer or us.. so take his comment with a grain of salt.

 

[Rick Darge]

So Jarred, what causes that minor looseness then?

 

[Steve Sherrick]

Before this spirals into a knock on the Nikon mount, let's make sure we clarify that it does not affect image and is really only noticeable to me when I wiggle the lens. Not when I'm focusing and changing aperture.

 

[Joel Kaye]

The play has no effect on the image at all, as far as I can tell.
...I'm just wondering why there is play in the Red Nikon mount but no play in my Nikon still camera... Red?

I've got some play, but I don't have a lens where the play affects either the image or the focusing. That is to say, if I focus the lens normally there is no play. If I grab the lens and rotate I can force the play. I have seen some lenses play more/easier than others.

It is important to be aware there are lenses whose focus mechanism does shift the image while focusing. That's not a problem caused by the Nikon mount.

 

[Evin Grant]

Jarred, I don't understand why this is an issue, it's a perfectly reasonable approach to making a Nikon mount and the play is a non-issue. If you've re-manufactured the K3 mount to tighter tolerances please let us know. Otherwise you can buy a replacement Nikon K3 mount at B&H...
http://www.bhphotovideo.com/c/product/366996-USA/Nikon_2717_K3_Female_Nikon_Bayonet.html

Here is the Nikon K3 extension ring...

Here is Red's Nikon Mount...

I've used the Red Nikon mount on a few jobs now, including second unit for a major feature film and it's preformed exquisitely.
And even the mount on my D3 has a little play. NO Nikon mount is positive lock!

 

[HD Hildebrand]

Mine moves and slightly shifts the image.

EDIT: I should add that it does not shift on a focus pull (focus rings turn with less tension), however the zoom rings have more tension and "can" cause the lens to shift in the mount if you are not careful or if you're aggressive, causing a slight shift in the image when it turns. It's not like an optical change, it's more like the image can move clockwise or counter-clockwise slightly - perhaps 1/4 of a degree.

 

[Anthony Gratl]

Mine moves and slightly shifts the image.

EDIT: I should add that it does not shift on a focus pull (focus rings turn with less tension), however the zoom rings have more tension and cause the lens to shift in the mount, slightly shifting the image when it turns.

well that's not good. This was a problem to me even without planetearth's post that goes one step further into the realm of real problem (i can only image that the movement increases with use and time as the mount gets worn, being as it's so thin and not snug to begin with)....

 

[Anthony Gratl]

And even the mount on my D3 has a little play. NO Nikon mount is positive lock!

Not to be contradictory Evin, but to me those videos aren't showing 'a little play' on a high end piece of photographic equipment. That play seems way over acceptable tolerances.
Mind you, I don't get into the details on technical specs, but if people are having movement on the lens, and now a report of the image shifting during a zoom, that's a red flag that ought to be addressed.

 

[Evin Grant]

The Nikon "F" mount was never designed to be a "Cinema" mounting solution. If you cannot work within it's capabilities rent or buy a set of PL mount lenses. The whole point of PL (Positive Lock) is to eliminate all movement at the mounting point. The PL does this quite well, whereas the Nikon mount was designed for quick, single handed removal and attachment of still lenses onto still cameras. Now we have the opportunity to use theses very well designed optics in an area that they are not intended. That does not make them a less viable option just one that needs to be considered as a price/performance relationship. No still zoom lens in it's original barrel will track like a cinema zoom regardless of the mount. By far my biggest issue with using still lenses (Now that I own cinema glass too) is the lack of distance and witness marks, all still lenses will have to be focused off the monitor, which is slower and much less comfortable to trained 1st ACs. But they will figure it out and it'll be fine as long as you can take the time hit.
If you're going light weight one man band though the Nikon's offer a distinct performance/weight advantage over cinema optics.

 

[Steve Sherrick]

As Evin has pointed out, the nikon solution is very useable in its current configuration. The play in the mount has been a non-issue and in fact I only took a look more carefully after Richard brought it up. I was curious. There is no doubt in my mind that still lenses will become even more popular with the Red especially once view factor and birger are on the scene. And if the p+s technic is used as well, even more will look to still lenses as an alternative to cine lenses.

But cine lenses clearly have some advantages right now, positive lock being one of them.