Flange distance issue

B.T,W
Zeiss 25mm 2.0 works perfect with focus infinity
You can put this lens on the list
Also tried the old version metal canon 50mm 1.8 OK !

I actu­al­ly have a nag­ging feel­ing the mount of the Black­mag­ic Cin­e­ma Cam­era flex­es with heavy lens­es so if you have infin­i­ty focus issues (like with the Tok­i­na 11-16mm) it might be worth check­ing for this and using rails to sup­port the larg­er lens­es when­ev­er pos­si­ble.

Don't think the weight of the lens is the issue. I and others are using a Canon 70-200mm (a.k.a. "The Magic Drain Pipe") on the BMCC with no barrel support and it infinity focuses fine. This lens is much heavier than the Tokina 11-16mm.

Wished you were right as that would be an easy fix.

Say it is the flange distance, which sounds like it probably is. Is the front metal piece removable so that it could be replaced? Are the electric contacts spring loaded such that moving the camera closer or further away would still allow contact? I'm assuming that if the distance needs to be change, the actual amount will be very small.

Is the front metal piece removable so that it could be replaced?

Yep it's removable via a few screws. I've taken it off and from the look of it there would be at least 1mm that could be made up by replacing this part. I think someone suggested this in another post. So if it isn't possible to simply have the sensor distance adjusted by BM then this would be another simple and fairly low cost avenue. Perhaps even a third party could develop a solution?

In the meantime, I'm looking for a Tokina 11-16 replacement that will focus and accept filters. Anyone with experience with the Canon 10-22mmm or the Sigma 10-20mm?

[Kristian Lam]

Hi,

If the focal flange distance is off, we can also adjust it under warranty.

Hang in there while we get to the bottom of this.

[Kristian Lam]

Don't think the weight of the lens is the issue. I and others are using a Canon 7-200mm (a.k.a. "The Magic Drain Pipe") on the BMCC with no barrel support and it infinity focuses fine. This lens is much heavier than the Tokina 11-16mm.

Wished you were right as that would be an easy fix.

The lens mount of the camera is very solid and flex is not an issue.

Hi,

If the focal flange distance is off, we can also adjust it under warranty.

Hang in there while we get to the bottom of this.

Thanks for posting this Kristian, this actually makes me feel a lot better!

I also thank Kristian Lam for weighing in. Surely helps to know that BM folks are on it.

well damn.. this camera's just too good to return.. I'm keeping it.. I hope BMD is hard at work on EF lens compatibility (I sure would love my 17-40 to be controlled) and the infinity focus thing.. audio quirks.. it's just too good of a camera to let this little things drag it down!

Greetings,
I wanted to take a moment to comment on this flange issue with some members. I'm probably one of the older members so please forgive me in advance of stating some of the obvious. Still lenses that we buy and mix and match are nowhere near the same quality as a true cinema lens you get from a rental house. I'm a fully professional cameraman I'm the union over 15 years and sadly have checked out lenses and found them to be off from Panavison ,CSC , and Clairmont. It is more common than we realize. As you handle the lenses put them in different temps it does force wear and tear on the mounts. The se holds true for our lens mounts. I check all of that carefully during a checkout. Now that your buying and commuting to the camera you will probably have to shim your lenses specifically to the BMCC for now. For my part I ordered a MTF version because the higher end mounts are adjustable to account for this potential problem. Take your camera to a rental house with a lens collimating and really check it out on the bench to be sure. The tech might have some great short term answers.

Thanks for posting Malc84cine, great to have your input.

Could you elaborate on shimming lenses. How exactly do you do this? And, can this be done with consumer lenses like the Tokina 11-16mm?

Greetings,
I wanted to take a moment to comment on this flange issue with some members. I'm probably one of the older members so please forgive me in advance of stating some of the obvious. Still lenses that we buy and mix and match are nowhere near the same quality as a true cinema lens you get from a rental house. I'm a fully professional cameraman I'm the union over 15 years and sadly have checked out lenses and found them to be off from Panavison ,CSC , and Clairmont. It is more common than we realize. As you handle the lenses put them in different temps it does force wear and tear on the mounts. The se holds true for our lens mounts. I check all of that carefully during a checkout. Now that your buying and commuting to the camera you will probably have to shim your lenses specifically to the BMCC for now. For my part I ordered a MTF version because the higher end mounts are adjustable to account for this potential problem. Take your camera to a rental house with a lens collimating and really check it out on the bench to be sure. The tech might have some great short term answers.

All valid info, but not applicable here. In this case, it appears that the mount is too far away from the sensor. Shimming would only make it worse. If the flange distance is in fact too long, then the only thing that would help is to install a shorter mount, or somehow move the sensor forward.

To be honest, if cinema lenses are better quality than lenses made for still photography is irrelevant. The still lenses focus perfectly fine on Canon cameras, so they should work on the BMCC with Canon mount, too. I'm curious to see what BMD will offer to rectify this, especially if every camera produced so far has the issue...

Thanks for posting Malc84cine, great to have your input.

Could you elaborate on shimming lenses. How exactly do you do this? And, can this be done with consumer lenses like the Tokina 11-16mm?

- to answer the question for both directions before we throw the baby out with the bath water. Take your camera and lenses to a camera shop with some reputable experience and have them look at the situation as I mentioned in my earlier post. The lenses are adjustable in small increments t both directions. If the camera is really offyou can see what BMCC's warranty and offices suggest first. I'm not implying voiding the warranty or sticking with a truly bad factory spec. Camera but after that having a good lens tech. Setting some of your lenses just for the BMCC'S could be a real viable option. In the early days of video everyone in the field pretty much set their own back focus on their lenses and that was that. When HD cam into vogue back focus became a much more serious concern in the video world than ever before. So all of the technology and manufacturing standards are still catching up to the standard of cinema lenses. So if you use consumer products they are going to have a looser tolerance than a pro standard.

To be honest, if cinema lenses are better quality than lenses made for still photography is irrelevant. The still lenses focus perfectly fine on Canon cameras, so they should work on the BMCC with Canon mount, too. I'm curious to see what BMD will offer to rectify this, especially if every camera produced so far has the issue...

All that you said is totally true but should work and it working 100% of the time is not my experience. I've used lenses that have come direct from the rental house just serviced sworn up and down were perfect yet was off. It happens sadly even at the highest levels of production but my whole point is every camera and lens I've ever used has a little work done on it to keep it up to that high standard.

Just de-shimmed my Tokina. Have infinity focus now. Will post info in Tokina focus thread: viewtopic.php?f=2&t=3807&p=32130#p32130

Thanks heaps Malc84cine, your suggestions have been super helpful!

I did another test with a Scarlet carefully calibrated to known good lenses (Zeiss) on an EF Titanium mount and moved them to the BMCC. They are spot on!

If BM has taken temperature extension into account (by pairing the right metals, e.g.), it should be fine. But I think the theory about Canon deliberately leaving leeway on their own cameras for "not so tight" tolerances on lenses should hold water then. You could always shim, but who wants to file their mount down?

One other thing before we get too upset I wanna add is, go to a rental house on an off day have them pull out an angienuex 10-1 look at their chart at various distances then look out a window and eye focus the lens what you find is your farthest distance by eye won't hit the infinity mark. Try it with a Panavision 24-250mm the same thing will happen. The reason is in the end infinity is theoretical. It's darn close but I've personally never hit it. This is where the depth of field charts become important because when you play with hyper focal you use that to truly hold infinity to like 50' in focus. What you really want to do is check your lenses ant various distances to see if your lenses are really off. Again before we start posting BMCC cheaping out we need to bench test the camera take it through some real paces with good tech's. personally I always bounce the lens back off infinity when ever I throw focus deep. I worry more when my focus marks don't line up at all meaning 10' is at 9'9 the still lenses have a lot of space like 10-20' that stuff really frustrates the guy that has to pull focus. Hope this adds. If your still not sure refer to Doug Hart's "Camera Assistant" manual he goes very deep on these issues.

Most of my lenses, also the ones that achieve infinity focus or go past it, do not hold focus after zooming on the BMCC (e.g. Canon 24-105mm F/4.0 IS L), whereas they do on my 5D Mark III. Why is that? This was also mentioned by someone else in another thread.

This is because the still lenses aren't true zoom lenses. Meaning me hi the lenses has to be designed with that in mind. This is one of the factors that make desinging a moving image zoom so expensive and hard. Red had this problem early on with the short zooms they first came out with.

Most of my lenses, also the ones that achieve infinity focus or go past it, do not hold focus after zooming on the BMCC (e.g. Canon 24-105mm F/4.0 IS L), whereas they do on my 5D Mark III. Why is that? This was also mentioned by someone else in another thread.

You sure? my 24-105L on my 5d mkii does not hold focus when zooming - it shifts slightly every time.

When zooming In it stays about right, zooming out tends to change the focal point. I have found other reports of this effect on 5d's and other canon dslr's when using this lens.

Did you do the exact same action on the BMCC as you did on your mark III?

The Canon EF 24-105 L is NOT a parafocal lens.

The Canon EF17-40, EF16-35 and EF70-200 2.8 NON-IS are the only Canon L zoom lenses that are parafocal.

HI Sean

My EF16-35 has the same problem as the non parafocal lens. With my BMCC any Canon L series lens I put on appears to not be parafocal.

Regards

Dave

Question regarding Flange distance. I do have a lot of knowlage about electronics, broadcast etc. But when i comes to lenses i'm a bit in the dark.

I can get my hands on a set of primes Zeiss CP.2 / Sony primes. But they are PL mount.

So i could buy a converter from PL to EF mount. As far as i know those things add a few milimeters extra between the original flange and the lens.

So the lens will be futher away from the sensor. What will be the consequence of this? Will i be able to get the lenses in focus?

After a bit of googling i did not find a very definitive anwser but found that some PL to EF adapters won't fit every PL lens as the back length of the flange. Also somebody mentioned that the MFT version of the BMCC would be a better fit for PL lenses.?

Somebody who can sed some light on this for me? Before i spend a lot of money on Glass that won't fit well on my still to come BMCC ?

You can adapt the CP's to EF with a special adapter made by Zeiss contact Camalot or Camera rentals in Amsterdam, PL lenses won't work mainly on EF, only on MFT due to flange distance.

PL back flange of the lenses are too close to the sensor, you won't be able to focus at all, and the quality of the lens is gone.

CP's are serious 'budget' cinema level lenses, if you don't have a focus puller, or have preplanned situations, their really 'useless', it's better to buy a Contax Zeiss set, you can buy a faster set for WAY less.

HI Sean

My EF16-35 has the same problem as the non parafocal lens. With my BMCC any Canon L series lens I put on appears to not be parafocal.

Regards

Dave

Do you have version I or II of the 16-35?

seam

Hey Sean

It's a version II

Also if the problem is with the lens, is it possible for Blackmagic to be in contact with Tokina's engineers to find a transparent solution to the problem that all of us can rally to. No one is in a better position than you.

Yup, I'll see what I can do.

Hi Kristian,

Wondering if you've made any progress.

Thanks

Just went to my reseller and tested my wide angle lenses with his demo cam.

Nikon 10-24 with Kipon sdapter: No infinity at 10-11 mm
Tamron 17-50 (Nikon Version) with Kipon adapter: No infinity at 17-23 mm

I´m very disappointed

I´ll order the Novoflex adapter now and test again but if that doesn´t work I´ll have to skip the EF version to see if MFT is woking.

Both lenses work great on a Canon 60D with the adapter.
Both work on my Nikon D7000
Both work with my Sony FS700 with Novoflex Emount adapter.

Edit: Just ordered the Novoflex and the cheap Kiwi adapter. Let´s hope...

Edit: Just ordered the Novoflex and the cheap Kiwi adapter. Let´s hope...

I tried the Kiwi adapter before buying the Novoflex and I had to return it.

I just got my camera today and have had infinity focus issues as well. I'm using OCT-19 lomo lenses, with a cieco adapter. In the past I was able to fit my 18/35/75/100 on a Canon EF. At the moment only the 100mm spherical, and 50mm/75mm anamorphics focus properly.

My 18/35/75 have all been serviced in the past year, and when set to infinity they are in focus on objects about 3 ft away. Perhaps it's my adapter...but very frustrating that I have a camera, accessories, and lenses....but can't shoot with it!

[Kristian Lam]

Hi guys,

I want to give you an update about this issue.

The cameras are all shimmed and calibrated to 44mm as per the reported focal flange depth of EF mount. I use the term "reported" as Canon does not publish the specifications officially so the exact expected tolerances are not known.

When checked against a collimated cine lens, we expect the Blackmagic Cinema Camera to get accurate focus according to the witness marks on the lens. For example, at focus chart placed 6 ft from the camera sensor plane will be in focus when the witness mark on the lens is at 6 ft.

When I tried the same collimated lens on some 5Ds, 7Ds and even a C300, the witness marks fall short of the expected distance which indicates to me that there's some fair amount of tolerances built into the Canon cameras to cater for still lenses where the tolerances are not as critical as cine lenses.

To address this, we need to put in the same allowances. We have tested this with some of the cameras from customers reporting this and it works.

If you think you're encountering this issue, please contact your local Blackmagic Design support office and we'll sort you out.

Thank you Kristian! The quick response, follow up testing. and fix makes me feel so good about purchasing this camera!

Yah, will contact my supplier.
Can you eleborate on what's involved Kristian?

Hi guys,

I want to give you an update about this issue.

The cameras are all shimmed and calibrated to 44mm as per the reported focal flange depth of EF mount. I use the term "reported" as Canon does not publish the specifications officially so the exact expected tolerances are not known.

When checked against a collimated cine lens, we expect the Blackmagic Cinema Camera to get accurate focus according to the witness marks on the lens. For example, at focus chart placed 6 ft from the camera sensor plane will be in focus when the witness mark on the lens is at 6 ft.

When I tried the same collimated lens on some 5Ds, 7Ds and even a C300, the witness marks fall short of the expected distance which indicates to me that there's some fair amount of tolerances built into the Canon cameras to cater for still lenses where the tolerances are not as critical as cine lenses.

To address this, we need to put in the same allowances. We have tested this with some of the cameras from customers reporting this and it works.

If you think you're encountering this issue, please contact your local Blackmagic Design support office and we'll sort you out.

Thank you for addressing this! Will cameras shipped from here on out be resolved of this problem?

Great to see the progress with this! one less thing to stop the camera from jumping on sets.

Now we just need MFT >:D

To address this, we need to put in the same allowances. We have tested this with some of the cameras from customers reporting this and it works.

If you think you're encountering this issue, please contact your local Blackmagic Design support office and we'll sort you out.

2 quick questions:

1) Will this fix be something we have to send our cameras in for?

2) Will this fix the problem with infinity focus on the Tokina 11-16?


Thanks very much for keeping us up to date on this problem, Kristian Lam. Much appreciated

[Kristian Lam]

[quote="MarshallHarrington"
Hi Kristian,

Wondering if you've made any progress.

Thanks[/quote]

I did contact Tokina but did not get a response

[Kristian Lam]

1) Will this fix be something we have to send our cameras in for?

2) Will this fix the problem with infinity focus on the Tokina 11-16?


Thanks very much for keeping us up to date on this problem, Kristian Lam. Much appreciated

1) Unfortunately, yes. The camera will have to be sent back to be recalibrated.

2) Yes, it will. However, this is on the assumption that the copy of the Tokina 11-16 is good as I've read that there are some out there with issues focusing to infinity on other cameras as well.

Excellent, thank you very much for your responses. I have contacted Blackmagic Support USA to send the camera in for recalibration asap. I did a bunch of tests today with various lenses and really need to go with something really wide like the Tokina. I hope this fixes it!

1) Will this fix be something we have to send our cameras in for?
2) Will this fix the problem with infinity focus on the Tokina 11-16?

1) Unfortunately, yes. The camera will have to be sent back to be recalibrated.

2) Yes, it will. However, this is on the assumption that the copy of the Tokina 11-16 is good as I've read that there are some out there with issues focusing to infinity on other cameras as well.

Excellent, thank you very much for your responses. I have contacted Blackmagic Support USA to send the camera in for recalibration asap. I did a bunch of tests today with various lenses and really need to go with something really wide like the Tokina. I hope this fixes it!

1) Will this fix be something we have to send our cameras in for?
2) Will this fix the problem with infinity focus on the Tokina 11-16?

1) Unfortunately, yes. The camera will have to be sent back to be recalibrated.

2) Yes, it will. However, this is on the assumption that the copy of the Tokina 11-16 is good as I've read that there are some out there with issues focusing to infinity on other cameras as well.

Did you go through the BlackmagicDesign website or is there another link? I would like my camera calibrated, but I also don't want it gone for a month either!

1) Will this fix be something we have to send our cameras in for?

2) Will this fix the problem with infinity focus on the Tokina 11-16?


Thanks very much for keeping us up to date on this problem, Kristian Lam. Much appreciated

1) Unfortunately, yes. The camera will have to be sent back to be recalibrated.

2) Yes, it will. However, this is on the assumption that the copy of the Tokina 11-16 is good as I've read that there are some out there with issues focusing to infinity on other cameras as well.

Hi Kristian,

Another member here asked about the cameras that will be shipped from now on, and there was no answer if they will be factory recalibrated or they will have the same problem.

[Kristian Lam]

1) Will this fix be something we have to send our cameras in for?

2) Will this fix the problem with infinity focus on the Tokina 11-16?


Thanks very much for keeping us up to date on this problem, Kristian Lam. Much appreciated

1) Unfortunately, yes. The camera will have to be sent back to be recalibrated.

2) Yes, it will. However, this is on the assumption that the copy of the Tokina 11-16 is good as I've read that there are some out there with issues focusing to infinity on other cameras as well.

Hi Kristian,

Another member here asked about the cameras that will be shipped from now on, and there was no answer if they will be factory recalibrated or they will have the same problem.

They will be have the new calibration.

I created a support ticket/email at blackmagicdesign.com

Did you go through the BlackmagicDesign website or is there another link? I would like my camera calibrated, but I also don't want it gone for a month either!

They will be have the new calibration.

Thank you Kristian for you immediate response. much appreciated

[CaptainHook]

When I tried the same collimated lens on some 5Ds, 7Ds and even a C300, the witness marks fall short of the expected distance which indicates to me that there's some fair amount of tolerances built into the Canon cameras to cater for still lenses where the tolerances are not as critical as cine lenses.

To address this, we need to put in the same allowances. We have tested this with some of the cameras from customers reporting this and it works.

Thanks Kris, does this mean that the allowances made will make collimated lenses now fall short on the BMCC like the other canon cameras, or are you able to make the allowances without causing issue for the cine lenses?

@Kristian Lam I bought my camera new and unopened from a private customer in the US who had ordered one too much from a US based distributor. Now the camera is in Norway. Where should it be sent for re-calibration??

PS. My Norwegian distributor was utterly unable to deliver the camera I had ordered from them in August.The relative neglect of European customers by BMD (BTW, heard about Europe? 450 Million people) has been an added cost as I had to get my camera at a higher price than the advertized retailer price. And I am not alone in this situation.

@Kristian Lam I bought my camera new and unopened from a private customer in the US who had ordered one too much from a US based distributor. Now the camera is in Norway. Where should it be sent for re-calibration??

PS. My Norwegian distributor was utterly unable to deliver the camera I had ordered from them in August.The relative neglect of European customers by BMD (BTW, heard about Europe? 450 Million people) has been an added cost as I had to get my camera at a higher price than the advertized retailer price. And I am not alone in this situation.

You can raise a support request on the site: http://www.blackmagicdesign.com/support ... lse&os=mac

They will the put you in contact with the correct agents.

Thanks Kristian,

If we send our cameras in for recallibration, will they have to go to Australia or will it be local (uk for me)?
Any idea how long the process could take?

Many thanks

Craig