Lens mount swap - Can I do it myself?

[Tonaci Tran]

So far my understanding is that lens mount swaps take some time and tools. If I wanted to swap between the b4 mount, nikon and pl, how hard would it be for someone with no experience to learn how to do it? Is lens mount swapping something that requires a lens technician/guru with years of experience to do? I'm curious as to whether this is a "don't do it yourself, bring it to a shop" situation?

Also, how long approximately does it take for someone to switch between lens mounts if they know what they are doing.

Apologies if this has already been answered and thanks in advance for any answers.

[Stephen Williams]

Hi,

If you know what your doing 10-15 minutes, probably 5 minutes if you don't!

Stephen

[TimothyD]

Hi Stephen,

Could you maybe answer a couple of questions:

Are special tools required?

What does the process entail?

Thanks so much,

Tim

[chuck colburn]

Hi,

If you know what your doing 10-15 minutes, probably 5 minutes if you don't!

Stephen

hahaha

so true

[Stephen Williams]

Hi Stephen,

Could you maybe answer a couple of questions:

Are special tools required?

What does the process entail?

Thanks so much,

Tim

Hi,

I think Chuck as a pro should answer that!

Stephen

[chuck colburn]

I've been giving this some thought and will reply this evening.

[Mike the beginner]

There's something fishy going on between you two:sarcasm:

Tools required: One tomahawk, large mallet and an old oily rag covered in sand.

Chuck i await your precise instructions........:umm:



Mike the beginner

[Stephen Williams]

Hi,

Last time I played with lens mounts I spent 5 hours trying to get the mount shimmed between 51.975 51.98. Within 20 minutes I could get that in places but it was not quite flat.....

I just took a camera to pieces that I bought from David Stump, I was convinced that the timing was slightly out. Having spoken to his tech. Ken Stone I wish I had left it well alone. I will see next week how long it takes me this time to set up the correct depth. If I am VERY lucky it will still be spot on! I wont hold my breath.

Stephen

[Martin Drew]

I presume lens mount changing instructions fall squarely into the realms of prediction at the moment, I haven't seen any info from Red about exactly how the mount change will work, so maybe you should add a Crystal ball to that tools list. That said the B4 mount is actually a B4 to PL adapter, so changes between PL and B4 should be straightforward.

M

[Stephen Williams]

I presume lens mount changing instructions fall squarely into the realms of prediction at the moment, I haven't seen any info from Red about exactly how the mount change will work, so maybe you should add a Crystal ball to that tools list. That said the B4 mount is actually a B4 to PL adapter, so changes between PL and B4 should be straightforward.

M

Hi

I think my predictions on mount collimation 6 months ago, were close to reality. The intermediate mount soloution has been dropped. I think Chuck with 30 years experiance of lens mounts, will be within a few microns of reality!

Stephen

[Martin Drew]

There is a good chance you are right Stephen, but there are a lot of questions unanswered by the Red camp, until we find out how the mount swap works it's all assumptions and speculation.

M

[chuck colburn]

Mike your right. Had to go fishing and morel hunting. (caught both and their on the grill).
Martin, yeah it's spectulation right now. what I want to talk about is the mechanics of the various lens mounts taking into account the fact that one is not going to use a depth micrometer to check the physical depth due to the fact that a video chip, not to mention the filter in front of it is not going to like the contact of it.
Anyhow this will have to wait till later due to undo influences. lol

[Roberto B]

here is a good question.. can you red guys help?

[Poi Boy]

The last time we discussed this we never heard from the Red guys. I'm hoping nikon to pl is not going to be Brain surgery, we'll have to wait and see.
Aloha
-A

[Jeff Kilgroe]

As far as the actual replacement of the mount, it should just be a few hex / allen screws and you're done. What worries me is that it's not going to really be field-replaceable as it leaves the sensor exposed throughout the process. There's also the distinct possibility that the mount will need to be shimmed and set properly, even involving collimation to ensure proper alignment. Makes me want to just stick with PL mount and keep my Nikon glass for my still cameras. Especially since I already plan to buy the RED 18-50 and most likely the 300mm. I can rent other glass, hopefully RED will consider selling that 85mm prime individually to complement the short zoom.

[Poi Boy]

I sure wish the Red guys would chime in here.......
-A

[Stephen Williams]

I sure wish the Red guys would chime in here.......
-A

Hi,

I hope they are working on a magic collimation function.

Stephen

[dalemccready]

Would it be a good idea for someone to design a depth micrometer that doesn't phyically measure but uses light/sound to guage depth leaving the sensor untouched? Do these already exist?

[Mike the beginner]

If the lens mount is secured by eight allen screws and suitable alignment pins to ensure the flange is properly lined up, then i would have thought the accurately machined and inspected mount flange should be the correct thickness.

Then to remove the PL mount would involve being in a suitable workplace free from wind, dust etc. The operation might involve slackening off on a diagonal opposing order each screw, repeat to fully slacken off and remove all screws. IF red have used locating pins to align flange with sensor, then depending on how tight the mount is located the mount flange may have to be removed by a small clamp.

The b4 mount and the nikon may be more complex than the canon?

I haven't a clue about mounts so this could be absolute rubbish :biggrin:

Chuck i hope you caught them on the fly..........

Mike the beginner

[Stephen Williams]

If the lens mount is secured by eight allen screws and suitable alignment pins to ensure the flange is properly lined up, then i would have thought the accurately machined and inspected mount flange should be the correct thickness.

Then to remove the PL mount would involve being in a suitable workplace free from wind, dust etc. The operation might involve slackening off on a diagonal opposing order each screw, repeat to fully slacken off and remove all screws. IF red have used locating pins to align flange with sensor, then depending on how tight the mount is located the mount flange may have to be removed by a small clamp.

The b4 mount and the nikon may be more complex than the canon?

I haven't a clue about mounts so this could be absolute rubbish :biggrin:

Chuck i hope you caught them on the fly..........

Mike the beginner


Hi Mike,

If every mount was perfectly collimated & every sensor was in exactly the same possition & totally flat life would be very easy. However if you ever dropped a mount on the floor or used a heavy lens without support you would once again have collimation issues.

Stephen

[Matt Uhry]

Would it be a good idea for someone to design a depth micrometer that doesn't phyically measure but uses light/sound to guage depth leaving the sensor untouched? Do these already exist?

I've been thinking about this too. I think you'll need to do it optically with a sharp, wide angle, high speed lens that you know is correct for infinity on the focus scale and a collimator.

If the lens focuses on the collimator target at infinity - then you are good. If it's a little beyond inf. you need to add shim. If it's a little too close remove some shim.

You could also do this on a work bench with a step target at a known distance, say 6 ft. Take the file into your computer and look at it critically. If the target that is at 6ft is good, you are good. If the one that's at 5ft 10 inches is sharper, add a bit of shim.

I hope it goes without saying that for this to work the lens must be accurately collimated and marked itself.

Here's picture a collimator I got for $125. I've lost track of the guy who made it... I wish I bought a few more, good stocking stuffer for DP friends.

Matt Uhry
www.mattuhry.com

[chuck colburn]

I've been thinking about this too. I think you'll need to do it optically with a sharp, wide angle, high speed lens that you know is correct for infinity on the focus scale and a collimator.

If the lens focuses on the collimator target at infinity - then you are good. If it's a little beyond inf. you need to add shim. If it's a little too close remove some shim.

You could also do this on a work bench with a step target at a known distance, say 6 ft. Take the file into your computer and look at it critically. If the target that is at 6ft is good, you are good. If the one that's at 5ft 10 inches is sharper, add a bit of shim.

I hope it goes without saying that for this to work the lens must be accurately collimated and marked itself.

Here's picture a collimator I got for $125. I've lost track of the guy who made it... I wish I bought a few more, good stocking stuffer for DP friends.

Matt Uhry
www.mattuhry.com

Right on Matt!

You just said one of the points I was going to bring up. The idea of a fixed focus lens setup to infinity is a great idea if one owns an autocollimator.
You can also check for parallelism of the lens mount to the film/sensor plane by using an optical flat sized to fit the lens seat and looking at the reflected image in the collimator. If the image of the optical flat overlaps the image of the sensor then your mount is parallel to the sensor plane. This is a very sensitive test and any diviation of parallelism shows up very easily in the eyepiece of the autocollimator.

http://www.surplusshed.com/pages/item/pm1076.html

When I was teching on location I used a Richter autocollimator with a "Maglite" light source. A very accurate and portable unit. Money well spent for peace of mind.

http://www.chamblesscineequip.com/catalog/Richter_Page%202.htm

http://www.chamblesscineequip.com/catalog/Richter%20102.htm

More later, as you guys are anserwing your own concerns here.
Oh and Mike, we fly fish on the river (ROGUE) but yesterday we were trolling up at Hyatt Lake using Ford Fender riggings.

[Matt Uhry]

The easy thing about collimation on the Red as opposed to a film style reflex viewfinder is that if it looks sharp it is sharp - there is no possibility of the ground glass being at a different distance than the film plane because it's the same Mysterium thing.

Lots of that residual nervousness that we are all having about swapping mounts, collimation, and the tech in the back room with the dial indicator does not apply.

Jannard & Co. have a taste for the burly when it comes to design and front of Boris and Natasha looked outrageously strong. I would expect it to repeatably hold very tight tolerances over many mount swaps.

Matt Uhry
www.mattuhry.com

[chuck colburn]

Matt,

Exactly.
I doubt if the camera front standard is being cast from pot metal. lol
Are you a cine tech? Cause you sure talk purty like one.

Chuck "A former tech in the back room" Colburn

[Jaime Vallés]

Does anyone know if RED will ship the camera with a specific mount already in place? If possible, I'd like the Nikon mount installed by them before shipping, since I have neither the tools nor expertise to properly do this, and will be using Nikon lenses right off the bat.

[Tonaci Tran]

We'll see what the RED team says, but it doesn't seem too much to ask for. I'm still crossing my fingers for some miracle RED tool that will enable user friendly lens mount swapping. Wishful thinking I know. I would love to have the flexibility to easily change the mount since I have pl mount lenses and canon lenses. I'm afraid that the complexity of this process will essentially restrict me to one lens choice for a duration if the swap is too difficult to do. Based on the reponses thus far, it is leaning towards more of a sophisticated process (at least for me it would be).

[chuck colburn]

I don't forsee mount swapping as any big deal if the base front of the camera body is held to a tight standard at the factory. It is not difficult to make different adaptable lens mounts. Richter lens standards are made to a .0001" tolerence and I never had a problem with any of those. If the mounts are attached with a series of allen head screws one could use a torque driver set to a given poundage and tighten the assembly the same way you would an engine head or the lug nuts on your car wheels. This would give you a repeatable tightning of the screws and result in a consistent flange depth.
Various folks have brought the fact that the Eclair ACL had interchangeable lens mounts. These were very nicely made of brass and steel with a substanial seating surface area and they repeated just fine. This would be my prefered method. And cripes if you don't like the way RED does it, have a machinist make one up to meet you requierments. It's really not that big of a deal.

[Mike the beginner]

I don't forsee mount swapping as any big deal if the base front of the camera body is held to a tight standard at the factory. It is not difficult to make different adaptable lens mounts. Richter lens standards are made to a .0001" tolerence and I never had a problem with any of those. If the mounts are attached with a series of allen head screws one could use a torque driver set to a given poundage and tighten the assembly the same way you would an engine head or the lug nuts on your car wheels. This would give you a repeatable tightning of the screws and result in a consistent flange depth.
Various folks have brought the fact that the Eclair ACL had interchangeable lens mounts. These were very nicely made of brass and steel with a substanial seating surface area and they repeated just fine. This would be my prefered method. And cripes if you don't like the way RED does it, have a machinist make one up to meet you requierments. It's really not that big of a deal.

Chuck i think you sumed up things pretty well there! Provided people are carefull and precise there should not be a problem.

Chuck i enjoy trolling loch lomond with large centre pin reels when the fish takes it is screaming reels for hundreds of yards before we get in control of things. Your part of the woods sounds fantastic for fishing!

I hope red team do not exaggerate the job of changing mounts. So far they have been up front on all things and i lke that aspect of honesty.

If people want to use still lenses and they can accomodate the weaknesses inherent in still lenses that should be ok with red team. So far i have found no evidence of sticking to PL mount from red team, that is good and fair.

Mike the beginner

[chuck colburn]

Chuck i think you sumed up things pretty well there! Provided people are carefull and precise there should not be a problem.

Chuck i enjoy trolling loch lomond with large centre pin reels when the fish takes it is screaming reels for hundreds of yards before we get in control of things. Your part of the woods sounds fantastic for fishing!

I hope red team do not exaggerate the job of changing mounts. So far they have been up front on all things and i lke that aspect of honesty.

If people want to use still lenses and they can accomodate the weaknesses inherent in still lenses that should be ok with red team. So far i have found no evidence of sticking to PL mount from red team, that is good and fair.

Mike the beginner

Mike,

You need to change you name to "Mike the Intermediate" lol
You know and understand much more than a beginner.
By "center pin reels" I take it that's the term in English speaking countries for a level wind? So far as hundreds of yards, what the heck are you hooking? Nessies off spring? lol
And I agree with you that I'm sure RED knows what they are doing.
What I would like to know is, if there is an air gap between the anti-aliasing filter and the face of the sensor. Why I ask this is, if there is, the aliasing (low pass filter) would act as an positive optical element which would increase the flange depth optically by appx. one third the thickness of the filter. So if one were to make a back focus testing lens they would have to take this increase into account if they were setting up the infinity focus lens on a standard PL or whatever particular lens back focus mount they were using with the collimator.

Chuck

[martinnoweck]

Can I use the Richter Fieldcollimator R2F also for adjusting / checking backfocus in the field - instead of the overpriced sharpmax?

martin

[Matt Uhry]

The Richter does the same thing as the Sharpmax - except it has a target that looks more like this...

http://www.vinland.com/Images/USAF-1951.gif

You would probably want to make some kind of collimator / lens interface so that it aligns quickly to the front of the lens. A cone of some kind ?

Anyone sitting in a room with a ricter and a 2/3 inch HD camera that can try it out and see how well it would work ?

Matt Uhry
www.mattuhry.com

[Stephen Williams]

Can I use the Richter Fieldcollimator R2F also for adjusting / checking backfocus in the field - instead of the overpriced sharpmax?

martin

Hi,

Yes, there was a guy who was making & selling on eaby for $175, he disconnued production when I wanted to buy one.

Stephen

[chuck colburn]

The Richter does the same thing as the Sharpmax - except it has a target that looks more like this...

http://www.vinland.com/Images/USAF-1951.gif

You would probably want to make some kind of collimator / lens interface so that it aligns quickly to the front of the lens. A cone of some kind ?

Anyone sitting in a room with a ricter and a 2/3 inch HD camera that can try it out and see how well it would work ?

Matt Uhry
www.mattuhry.com


Matt,

I made and adjustable for heigth system for my Richter that just mounted on the mattebox rods. Was good to go for whatever camera/lens system we were using.

Chuck

[martinnoweck]

Hi Stephen,

what was the name of the guy and / or his company?

Martin

[martinnoweck]

Hi Matt,

I thought about something more reliable than a Test Chart for Field Production with ENG-Zoom Lenses, but as far as I know there is only the Sharpmax, which cost around 5.000,- Euros?

Martin

[Stephen Williams]

Hi Stephen,

what was the name of the guy and / or his company?

Martin

Hi Martin,

Thomas Thomosy, he has written books on camera repair.

http://www.homestead.com/cameratester/

Stephen

[martinnoweck]

Thanks Stephen, i love the wooden stand for the cameratester ;-)

but serious, are there any thoughts on this subject?

Martin

[Stephen Williams]

Thanks Stephen, i love the wooden stand for the cameratester ;-)

but serious, are there any thoughts on this subject?

Martin

Martin,

Then you will love this, it's where I got the link in the first place!

http://www.geocities.com/leafshooter/collimator.htm

Stephen

[chuck colburn]

The Richter does the same thing as the Sharpmax - except it has a target that looks more like this...

http://www.vinland.com/Images/USAF-1951.gif

You would probably want to make some kind of collimator / lens interface so that it aligns quickly to the front of the lens. A cone of some kind ?

Anyone sitting in a room with a ricter and a 2/3 inch HD camera that can try it out and see how well it would work ?

Matt Uhry
www.mattuhry.com

Hi Matt,

I hadn't payed any heed to the Sharpmax before so I looked it up on a few sites. It appears to be a collimator, but not an autocollimator. What it does is present and infinity focused image of a siemens star and that's all it does. It is meant to be used only when you have an imaging lens on the camera. Where as an autocollimator, (which means you can view the reflected image thru the collimator) allows many different types of optical checks. In fact you don't even have to have a lens on the camera for one certain test (checking of parallelism of the lens seat to the film/sensor plane) a very important check with a camera that has interchangeable lens mounts. Also you can check the off axis quality of a given lens something that can't be done with the Sharpmax. So it seems that the Sharpmax is an extremely exspensive source of infinity focus designed to easily attach to the front of a camera lens and thats about it. You could make one from an off the shelf reticle and an enlarging lens and a flash light. Also the Richter unit will allow you to measure line pair resoultion of a given lens. So unless I missed something in the stuff I read about the Sharpmax, you can buy a new Richter autocollimator for about 1/4 the price and get a tool that is alot more versital. Also I don't believe the Sharpmax even comes with a tube of lubricant.

[martinnoweck]

Hi Chuck,

good research, that is exactly what the Sharpmax does:

it is a backlit Siemensstar, you put in front of the lens of the HD-Camera (for example Digiprime or Zoomlens), set the focus on the lens to infinity and control / adjust the backfocus of the lens.

it is Euro 4.500,- for the sharpmax and Euro 500,- for different attachment options for different lenses.

Martin

[martinnoweck]

Martin,

Then you will love this, it's where I got the link in the first place!

http://www.geocities.com/leafshooter/collimator.htm

Stephen

Stephen,

absolutely right - i love this link!

Thanks,
Martin

[chuck colburn]

Hi Chuck,

good research, that is exactly what the Sharpmax does:

it is a backlit Siemensstar, you put in front of the lens of the HD-Camera (for example Digiprime or Zoomlens), set the focus on the lens to infinity and control / adjust the backfocus of the lens.

it is Euro 4.500,- for the sharpmax and Euro 500,- for different attachment options for different lenses.

Martin

In which case it should come with two or more tubes of lubricant! lol

[martinnoweck]

hehe!

[chuck colburn]

Stare into the center of this target for 30 seconds without blinking and you won't need a Sharpmax!

http://www.sinepatterns.com/images/Sector%20Star.gif

[chuck colburn]

Martin,

Then you will love this, it's where I got the link in the first place!

http://www.geocities.com/leafshooter/collimator.htm

Stephen

That's great! And it is everything an autocollimator has to be. Not to portable though and his method of inital calibration is a bit on the coarse side. lol
Speaking of calibration... If anyone happens to buy a Richter type autocollimator and wants to check to be sure the objective is in proper infinity focus you can unscrew the eyepiece and mount it on the back of the optical block where the light source mounts. Then view something far away to simulate infinity (we liked using the moon at half phase as it was a nice bright target against a black back ground)and if the image of the terminator of the moon and the resoultion pattern are both in focus at the same plane your unit is in proper order.

Chuck

[Roberto B]

Hi

I think my predictions on mount collimation 6 months ago, were close to reality. The intermediate mount soloution has been dropped. I think Chuck with 30 years experiance of lens mounts, will be within a few microns of reality!

Stephenstephen.. http://clicksmilies.com/s1106/waffen/violent-smiley-010.gif

"Not sure what the doubt is... the mount is split into two parts. The 1st part is calibrated at the factory. The 2nd part is a quick change in the field.

Jim" 05-19-2007

http://clicksmilies.com/s1106/waffen/violent-smiley-031.gif :calm:

[Stephen Williams]

stephen.. http://clicksmilies.com/s1106/waffen/violent-smiley-010.gif

"Not sure what the doubt is... the mount is split into two parts. The 1st part is calibrated at the factory. The 2nd part is a quick change in the field.

Jim" 05-19-2007

http://clicksmilies.com/s1106/waffen/violent-smiley-031.gif :calm:

Hi,

It's the 2nd part that I am worrying about! That's sounding like the old intermediate mount has returned.
What happens when a heavy zoom has been used without support?
I don't know where Jim posted that, but nobody from the Red camp has responded to this thread.

Some people are bothered about lens collimation, some not.

Stephen

EDIT FWIW how tight you adjust those bolts will effect the FFD by several microns

[Roberto B]

jim didn't post but i'm not a liar.. jim words sic

[Stephen Williams]

jim didn't post but i'm not a liar.. jim words sic

Hi,

I am sure Jim & everybody here would like it to be that easy! When 500 cameras are in the field we will have a better idea.

I am curious how the problems that have affected film cameras + lenses for the last 100 years will suddenly become a non issue, especially as I am under the impression that the tolerances for a digital sensor will be tighter than for film.

Stephen

[chuck colburn]

Hi,

I am sure Jim & everybody here would like it to be that easy! When 500 cameras are in the field we will have a better idea.

I am curious how the problems that have affected film cameras + lenses for the last 100 years will suddenly become a non issue, especially as I am under the impression that the tolerances for a digital sensor will be tighter than for film.

Stephen

Hello Stephen,

I think, and this is just a guess, that perhaps RED is working with a third party/parties to produce different lens mounts for different lenses. And perhaps that is why no detailed info on the front end configuration has been released. I would do just that if it were my operation as a company with the background in cameras and optics would be the best choice to produce such products. Or perhaps they are just to damn busy right now! lol Anyhow as you say some people are not to concerned about the mount swapping thing (me for one) if it is done in a proper manner.

Chuck

[Jannard]

The lens mount is one of 100 critical design problems to solve in this project. No solution will be perfect when it comes to holding tight tolerances when changing lens mounts. We think we have the best solution for our camera. And if it turns out we can make it better, we will. As of now, we are happy with the solution.

Jim

[Emanuel A.]

Thanks for the update Jim. And if you're happy we are too!

[Jay A. Kelley]

The lens mount is one of 100 critical design problems to solve in this project. No solution will be perfect when it comes to holding tight tolerances when changing lens mounts. We think we have the best solution for our camera. And if it turns out we can make it better, we will. As of now, we are happy with the solution.
Jim

I still have no idea what's going on with all this.. I guess it means the adaptors will work perfectly since they feel good enough about them to charge between 500 - 3500 a piece
Jay

[Stephen Williams]

I still have no idea what's going on with all this.. I guess it means the adaptors will work perfectly since they feel good enough about them to charge between 500 - 3500 a piece
Jay

Hi Jay,

The $500 one is not an adapter.

Stephen

[Gordon Prince]

What's your problem with the changing mounts Stephen? Do you think your cine lenses will remain obsolete?

[Stephen Williams]

What's your problem with the changing mounts Stephen? Do you think your cine lenses will remain obsolete?

Hi Gordon,

I am getting fast at changing & collimating mounts, probably helps that the mount was set up by a Mr Stump. All I had to to was adjust the torque of the screws, & then checking with a depth gauge. I got 51.975 but if I slightly pressed the steel plate 51.98! Most of my lenses are PL mounted so will probably be in use after I am dead.

Stephen

[Gordon Prince]

Ah Ah Ah!

[chuck colburn]

Hi Gordon,

I am getting fast at changing & collimating mounts, probably helps that the mount was set up by a Mr Stump. All I had to to was adjust the torque of the screws, & then checking with a depth gauge. I got 51.975 but if I slightly pressed the steel plate 51.98! Most of my lenses are PL mounted so will probably be in use after I am dead.

Stephen

Hi Stephen,

About your heirs.........

[jaadgy akanni]

Hi Stephen,

About your heirs.........

hahahaha...that made my day. Good comics on this forum.:biggrin:

[Jay A. Kelley]

Hi Jay,

The $500 one is not an adapter.

Stephen

Hey Stephen,

If it's not an adaptor, then what is it and what are you so concerned about?

I really need to learn about this but you guys are talking a little over my head.. Please explain this thread to an idiot.. Of which I am one!
Jay

[Emanuel A.]

Hey Stephen,

If it's not an adaptor, then what is it and what are you so concerned about?

I really need to learn about this but you guys are talking a little over my head.. Please explain this thread to an idiot.. Of which I am one!
Jay

Jay,

You're wrong you're not an idiot... ;-) BTW, Congrats regarding your new baby acquisition -- that's such an achievement! (we're waiting for your pics' thread!)

An adapter is different than a mount since you need any sort of mount and you'll swap the original PL mount, not adding an adapter.

That's why I always thought the RED's intermediate mount would/shall solve any hassle, isn't it so? Won't the 2nd part of the intermediate mount work as a kind of an adapter? Where the tight tolerances won't count...? (though I think that only the RED team may answer us as soon as they have/get it)

[Stephen Williams]

Hey Stephen,

If it's not an adaptor, then what is it and what are you so concerned about?

I really need to learn about this but you guys are talking a little over my head.. Please explain this thread to an idiot.. Of which I am one!
Jay

Hi Jay,

Basically you swop the front of the camera which has the mount attached to it. If both 'mating' surfaces are made with a tolerance of +/- 1.25 microns then the biggest error that could occur is 5 microns. The lens mount must also be totally FLAT! Any dirt or dust in between the 2 surfaces will not help!

If the mount is too big one grinds it down and adds shims if it's too small, that has been the standard practice with film cameras for 100 years. As lenses get wider & faster the accuracy becomes more important.

It's also very important to check that the lens is clean before attaching it. If you check the mounts on most 2/3 " cameras you will find them to be scratched & dirty.

Stephen

[Stephen Williams]

That's why I always thought the RED's intermediate mount would/shall solve any hassle, isn't it so? Won't the 2nd part of the intermediate mount work as a kind of an adapter? Where the tight tolerances won't count...? (though I think that only the RED team may answer us as soon as they have/get it)

Hi Emanuel,

With an intermediate adapter there are 4 'mating surfaces' rather than 2, so everything has to be even more accurate.

Stephen

[Michael Hastings]

Hi Jay,

It's also very important to check that the lens is clean before attaching it. If you check the mounts on most 2/3 " cameras you will find them to be scratched & dirty.

Stephen

You make a good point, I think a lot of us coming to this from the video world would have to admit that many - not all - video people are a little sloppy in this regard, and may have to clean up our act when coming from the .35 megapixel standard def world (or even most high def video at 1 to 1.5 megapixels) where we could get away with a lot - to ultrahigh resolution world of RED.

Also when adjusting the mount when changing from one to the other - say the PL to the Birger canon mount, are we likely to be able to adjust it just with the tightening of the screws or are we going to have to have a set of shims available. I ask this assuming that at least the first time we use a new mount we will need to shim or grind - I'm thinking more of the "field" changes.

[Stephen Williams]

Also when adjusting the mount when changing from one to the other - say the PL to the Birger canon mount, are we likely to be able to adjust it just with the tightening of the screws or are we going to have to have a set of shims available. I ask this assuming that at least the first time we use a new mount we will need to shim or grind - I'm thinking more of the "field" changes.

Hi,

It all depends on the accuracy of the different mounts. Historically mounts were made slightly under size so that shims could be added. Much easier than grinding.

People may also want to get their Nikon & Canon lenses collimated.

Stephen

[Jay A. Kelley]

Thanks guys! Now I understand better
Jay