Flange distance issue

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Larry Sellers

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Flange distance issue

PostSun Jan 20, 2013 8:52 am

I'm beginning to think that the flange distance of the BMCC lens mount may be just the slightest bit off compared to canon cameras. With all of the reported Tokina issues combined with my own experiences, it's leading me to believe this is the case. My tokina 11-16 has no problem reaching infinity on my 7D or my FS100 with adapter. I can't hit infinity on the BMC unless I stop way down.

Then today I used a buddy's 17-55 f2.8 IS and it won't hit infinity at 17mm. I had previously used another copy of the same lens and it was fine.

I'm thinking that there are inconsistencies from copy to copy of various lenses. My other two cameras seem to roll with these differences just fine. Maybe the flange distance on the BMC is just a hair longer than canon cameras, leaving no room for error.

BMD, please chime in here. I'd love to hear from a tech to confirm or deny my theory and if there is anything that can be done to adjust flange distance.
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Nilscrompton

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Re: Flange distance issue

PostSun Jan 20, 2013 1:35 pm

My belief is that the BMCC is bang on 44mm, and that if we were all putting perfectly calibrated lenses on them it'd be fine. My other hunch is that Canon shorten their flange on consumer equipment given the nature of consumer lenses, and quite possibly Tokina are chasing that measurement so as not to loose front focusing on an 11mm lens at f2.8... All speculation of course, but I agree, the FFD spec seems to differ.

Regardless, the way to fix this issue is to get your problem lenses exchanged or corrected, and then if it's still out, ask Blackmagic Support (who are very lovely btw) to check the FFD on your BMCC.

I've sent my Tokina to Adeal in Melbourne who service these lenses here to take a look under warantee. I also called Blackmagic support (who are very lovely btw) and they said if there were a FFD adjustment needed on the camera then it would be covered under warrantee. I'll report back with how it goes.

It's funny, I didn't even know what FFD meant a week ago. And I didn't even know my Tokina was soft on my Canon... :lol:
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Christian Schmeer

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Re: Flange distance issue

PostSun Jan 20, 2013 4:12 pm

My Canon 40mm F/2.8 Pancake lens also doesn't reach infinity focus and at 40mm it's not that wide :roll:
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Nilscrompton

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Re: Flange distance issue

PostSun Jan 20, 2013 9:17 pm

Have you checked your 40mm on your Canon? My 35mm is out on the BMCC too, and testing it on my Canon reveals that it doesn't quite hit infinity there either. It's more pronounced on the BMCC though.

Another easy way to compare is to get a lens that does hit infinity on both systems, and mark those points on the lens barrel (easier with a Nikon lens).

If you feel it's necessary, ring Blackmagic support or send them an email, they're quite responsive.

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sean mclennan

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Re: Flange distance issue

PostSun Jan 20, 2013 10:31 pm

"Then today I used a buddy's 17-55 f2.8 IS and it won't hit infinity at 17mm. I had previously used another copy of the same lens and it was fine. "

If it worked fine for one lens and not the other, it's definitely not the mount ont he BMCC, it's the lens.
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Christian Schmeer

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Re: Flange distance issue

PostSun Jan 20, 2013 11:21 pm

nilsonium wrote:Have you checked your 40mm on your Canon? My 35mm is out on the BMCC too, and testing it on my Canon reveals that it doesn't quite hit infinity there either. It's more pronounced on the BMCC though.


Just checked it on my 5D Mark III and it goes very slightly past infinity focus on that camera :/
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Larry Sellers

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Re: Flange distance issue

PostMon Jan 21, 2013 8:24 am

sean mclennan wrote:
If it worked fine for one lens and not the other, it's definitely not the mount ont he BMCC, it's the lens.



well, yes and no. theoretically, if the BMC flange distance is dead on to canon's spec, then technically the camera is not the issue. but, if canon knows that there will be a margin of error from lens to lens and leaves a little wiggle room in their own flange distance, then so should BMD.

for me, this is 2 lenses in 2 days that can't hit infinity. on my 7d, every lens i own goes to infinity and beyond, buzz lightyear style. you dig?
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Nilscrompton

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Re: Flange distance issue

PostWed Feb 06, 2013 2:33 am

I dig.

Got my Tokina serviced, they claim it's now spot on. Still no joy, have tried the 3 screws trick. No joy. Contacted BM Support, they asked for a single DNG from my cam of anything. Have sent it off and am waiting for a response.

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Marshall Harrington

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Re: Flange distance issue

PostWed Feb 06, 2013 3:06 am

Christine, I've got to wonder why an engineer from BMD won't get in on this. One way or the other. It would be a much better solution than the contentious posts that go on and on. How about a response from BMD.
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Dennis Nomer

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Re: Flange distance issue

PostWed Feb 06, 2013 8:34 am

I fail to comprehend the 'wiggle room' concept, unless they are expecting people to use shims. If there is a spec for a distance, you want to hit that distance as accurately as possible. Since the imaging chip and a camera lens mount are normally hard-mounted, I would expect the lens maker to have special adjustments (that they do with a jig in the factory before shipping) to adjust for minor variations in parts. Then again, maybe I am wrong. Perhaps the camera folks find it cheaper to relax the tolerances on machining and mounting, and just measure during assembly and shim to hit the spec.

Even so, this is an important issue to chase and keep a close watch on, and I will be following the results.
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Noel Sterrett

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Re: Flange distance issue

PostWed Feb 06, 2013 1:06 pm

MarshallHarrington wrote:Christine, I've got to wonder why an engineer from BMD won't get in on this. One way or the other. It would be a much better solution than the contentious posts that go on and on. How about a response from BMD.


One did on January 13:

Kristian Lam wrote:Hi

We are happy to investigate but given that all lenses focus correctly except this particular one, I'm inclined to think that maybe there is an issue with the Tokina lens?


There are too many reports of infinity focus problems with too many lenses for this to simply be a lens issue.

The real question is what can be done about the problem.

Cheers.
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Kristian Lam

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Re: Flange distance issue

PostThu Feb 07, 2013 5:07 am

MarshallHarrington wrote:Christine, I've got to wonder why an engineer from BMD won't get in on this. One way or the other. It would be a much better solution than the contentious posts that go on and on. How about a response from BMD.


Hi,

We manufacture the cameras to be as accurate as possible to the EF flange focal distance of 44mm.
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Marshall Harrington

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Re: Flange distance issue

PostThu Feb 07, 2013 5:40 am

Kristian Lam wrote:
MarshallHarrington wrote:Christine, I've got to wonder why an engineer from BMD won't get in on this. One way or the other. It would be a much better solution than the contentious posts that go on and on. How about a response from BMD.


Hi,

We manufacture the cameras to be as accurate as possible to the EF flange focal distance of 44mm.


Thanks for getting back Kristian.

Those of us who keep pushing on this are not trying to finger point, just so you are sure of that. While I'm personally not an engineer I keep wondering what are the possibilities that would cause this problem. If the problem is with the lenses what do you suspect the problem to be. 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.

That act would represent a strategy from a company that put it's clients first. This would be a giant leap forward to the already giant leap forward that the Blackmagic Cinema Camera represents.
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Kholi Hicks

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Re: Flange distance issue

PostThu Feb 07, 2013 5:57 am

Hmm... maybe it has to do with the lack of an OLPF? Wouldn't that cause backfocus issues or inconsistencies?

I remember reading that if you remove the OLPF from certain cameras, you have to replace it with something else (glass) so that you don't run into Back Focus problems.

Is that what we're seeing here?
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Kristian Lam

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Re: Flange distance issue

PostThu Feb 07, 2013 6:14 am

Kholi wrote:Hmm... maybe it has to do with the lack of an OLPF? Wouldn't that cause backfocus issues or inconsistencies?

I remember reading that if you remove the OLPF from certain cameras, you have to replace it with something else (glass) so that you don't run into Back Focus problems.

Is that what we're seeing here?


We don't have an OLPF but there is a filter in front of the sensor and that has been taken into account.
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Kristian Lam

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Re: Flange distance issue

PostThu Feb 07, 2013 6:17 am

MarshallHarrington wrote:
Kristian Lam wrote: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.
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Kholi Hicks

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Re: Flange distance issue

PostThu Feb 07, 2013 7:21 am

Ah got it, Iv'e never actually gone snooping around inside of the barrel, not sure why I assumed there was just nothin' there.

Carry on!
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adamroberts

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Re: Flange distance issue

PostThu Feb 07, 2013 8:28 am

Kristian Lam wrote:We don't have an OLPF but there is a filter in front of the sensor and that has been taken into account.


Just a thought... Perhaps the glass thickness has changed when the sensor bonding process issues were being resolved?
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Marshall Harrington

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Re: Flange distance issue

PostThu Feb 07, 2013 4:04 pm

Kristian Lam wrote:
MarshallHarrington wrote:
Kristian Lam wrote: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.


That response represents everything good about this forum and the BMCC community. Thank you!

FYI early on I copied the folks at Tokina. Never heard any type of response which does not really surprise me. I do think that you will have better luck.
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Kristian Lam

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Re: Flange distance issue

PostFri Feb 08, 2013 3:16 am

adamroberts wrote:
Kristian Lam wrote:We don't have an OLPF but there is a filter in front of the sensor and that has been taken into account.


Just a thought... Perhaps the glass thickness has changed when the sensor bonding process issues were being resolved?


Very unlikely as that would have been picked up when we calibrate the camera.
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Uli Plank

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Re: Flange distance issue

PostFri Feb 08, 2013 9:37 am

It's not simply about "wiggle room". I have used quite a few professional cine lenses and heaps of good stills lenses. They all focus a tad beyond infinity!

It's needed, there are not only inevitable production tolerances, even under tightest QC, but temperature changes as well. Plus, electronic lenses carry looser tolerances than manual ones, that's inevitable not to stress the tiny motors in them. We are talking fractions of a millimeter here, and even the combination of materials used for the lens mount and the ones carrying the sensor matters when heat or cold strikes. The RED One suffered from that, but at least you could adjust it yourself. They cured it in the Epic/Scarlet with a better choice of materials, which are compensating each others temperature effects, but they still have an (even better) mechanism for adjusting flange distance.

The BMCC has no such provision, but it needs even higher precision, since we need shorter focal lengths for the smaller sensor. Flange distance is more critical the wider the lens is, that's why we see it in the Tokina at 11 but not at 16mm.

I have compared the same lenses on an Epic which was carefully adjusted for flange distance by a professional service and the BMCC, using adapted Zeiss Contax primes and the Tokina. All lenses focus a tad beyond infinity on the Epic, but the witness marks are dead on. The same Contax lenses focus just to infinity on the BMCC at room temperature, and they are not as wide (obviously) as the Tokina.

Sorry, BM, but we have a problem here. There are not many choices to replace the Tokina, which is very good for it's price on RED and very attractive if one chooses the EF version of the BMCC. I hope the MFT version will do better, I'm looking forward to use the beautiful lenses from Cosina/Voigtländer.
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Felix Steinhardt

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Re: Flange distance issue

PostFri Feb 08, 2013 1:18 pm

Oops, that doesn´t sound good at all!

I have just bought the Nikon 10-24mm and if it turns out it doesn´t work, I´ll sell the camera right away.

What are the wide angle options anyway?
The Sigma 8-16 seems to work but is totally slow and Sigma...
Tokina 11-16 -> No luck, even some Nikon version don´t work, so it´s not worth a try.
Nikon 10-24 -> We´ll find out when I get mine, but since I´m European that will be Xmas 2013.
Canon 10-22 -> No luck, no iris control and no tests if it reaches infinity.
Tamron 10-24 -> Received the worst reviews by customers because it´s so soft.
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Uli Plank

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Re: Flange distance issue

PostFri Feb 08, 2013 2:24 pm

I had the chance to test another Tokina 11-16 sample.

Turns out that the issue must be on both sides: this one is even worse on the BMCC, but barely touches infinity @ 11mm even on the RED Epic, while ours is safely getting there. Sample variation seems to be massive with these Tokinas, I can understand why professionals swear on getting them re-housed to PL by Duclos. The glass is great, but mechanical precision seems to be a game of luck. If we only could adjust flange distance by ourselves…
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Kholi Hicks

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Re: Flange distance issue

PostFri Feb 08, 2013 3:40 pm

If you google around you'll find that the 11-16 has issues in general, always has.

Another user reported that his Canon 28/2.8 couldn't infinity, but my 28/1.8 USM does. Slightly beyond, in fact.

I don't think it rests only on the camera.
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danap

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Re: Flange distance issue

PostFri Feb 08, 2013 3:47 pm

unlikely? ...MURPHY'S LAW....
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Marshall Harrington

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Re: Flange distance issue

PostMon Feb 11, 2013 4:34 pm

Kristian Lam wrote:
MarshallHarrington wrote:
Kristian Lam wrote: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.


Kristian . . . just wondering if you are having any luck with contacting Tokina?

I've been wondering if Matthew Duclos is following this post? I'm planning on sending him a Tokina for a Cinemod and knowing that they have a somewhat rebuilt Tokina of this model he might be an authoritative voice to weigh in on.

Thanks again for your getting into all this.
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Abobakr M. Alshiblie

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Re: Flange distance issue

PostMon Feb 11, 2013 7:11 pm

MarshallHarrington wrote:
Kristian . . . just wondering if you are having any luck with contacting Tokina?

I've been wondering if Matthew Duclos is following this post? I'm planning on sending him a Tokina for a Cinemod and knowing that they have a somewhat rebuilt Tokina of this model he might be an authoritative voice to weigh in on.

Thanks again for your getting into all this.


I emailed the Tokina guys through a message regarding my lens flange distance issue with the Blackmagic and I even directed them a link to the thread in the bmcuser forum, about a week ago but they didn't reply
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Kristian Lam

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Re: Flange distance issue

PostMon Feb 11, 2013 10:46 pm

MarshallHarrington wrote:Kristian . . . just wondering if you are having any luck with contacting Tokina?


I'm still working on it.
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Marshall Harrington

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Re: Flange distance issue

PostMon Feb 11, 2013 11:16 pm

Kristian Lam wrote:
MarshallHarrington wrote:Kristian . . . just wondering if you are having any luck with contacting Tokina?


I'm still working on it.

Thanks Kristian . . . sent an email to Matthew Duclos. Hoping he checks in. He really knows this lens and I'm sure the folks at Tokina as well. That might help.
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Phillip Mortimer

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Re: Flange distance issue

PostMon Feb 11, 2013 11:24 pm

--- Update 5 March 2013 ---

My camera has been adjusted by Blackmagic and I can now achieve infinity focus with all my lenses, including the Tokina 11-16, Voigtlander 40mm and Zeiss 85mm.

--- Original post ---

I have tried a number of lenses from Zeiss, Voigtlander, Nikon, Tokina and Canon on two separate BMCCs. My manual focus EF mount lenses from Zeiss and Voigtlander with a hard infinity stop cannot focus to infinity on either BMCC. My Nikon mount manual focus lenses cannot focus to infinity on the BMCC when used with a high quality Rayqual adapter, but do focus to infinity when used with a cheap eBay adapter. My Canon autofocus lenses all focus past infinity by design, and can all achieve infinity focus on the BMCC. All these lenses can focus to infinity on both my Canon 5D mark III and 500D.

Results from 1st BMCC received early January. I tested the infinity focus on the camera and put some files here: http://www.phillipmortimer.com/BMCC/. Follow the link and right click to download them if you are interested. The tall building in the background is the Tokyo Metropolitan Government building which is approximately 5km from my apartment and is my infinity reference.
    01 Nikon 28mm f2.8 Ai-S with high quality Rayqual Nikon to EOS adaptor. Furthest focus ~10m.
    02 Nikon 28mm f2.8 Ai-S with cheap eBay adaptor which is too thin. Can achieve infinity focus. Indeed you can focus past infinity with this adaptor on both the BMCC and my Canon cameras.
    03 Voigtlander 58mm f1.4 Nikon F mount. Rayqual adaptor. Furthest focus ~40m.
    04 Voigtlander 58mm f1.4. eBay adaptor. Can achieve infinity focus.
    05 Voigtlander 40mm f2. EOS mount version. Furthest focus ~20m.
    06 Zeiss 85mm f1.4. EOS mount version. Furthest focus ~70m.
    07 Tokina 11-16mm f2.8 at 11mm. EOS mount version. Furthest focus ~2-3m.
      As a control, same lenses on other cameras:
    08 Tokina 11-16mm f2.8 at 11mm on Canon 5D mark III. Can achieve infinity focus.
    09 Voigtlander 40mm f2 on Canon 5D mark III. Can achieve infinity focus.
    10 Zeiss 85mm f1.4 on 5D mark III. Can achieve infinity focus.
    11 Tokina 11-16mm on 500D. Can achieve infinity focus.
I contacted Blackmagic support in Japan who were fantastic and arranged for the camera to be replaced. I received the replacement camera last week. It has the same problem.

Here are the files for the second camera. http://www.phillipmortimer.com/BMCC2/
    01 Zeiss 85mm f1.4 EOS mount version. Furthest focus again about 70m.
    02 Voigtlander 40mm f2 EOS mount version. Furthest focus again about 20m.
    03 Tokina 11-16mm f2.8 EOS at 11mm EOS mount version. Furthest focus ~1m.
      Again, as a control, on my 5D mark III:
    04 Zeiss 85mm f1.4 on 5D mark III. Can achieve infinity focus.
    05 Voigtlander 40mm f2 on 5D mark III. Can achieve infinity focus.
Last edited by Phillip Mortimer on Tue Mar 05, 2013 11:51 am, edited 1 time in total.
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Cam Macduff

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Re: Flange distance issue

PostTue Feb 12, 2013 9:25 am

Wow, awesome work Phillip, thanks!
Think we're seeing a pattern here possibly when you consider all the other people here with similar results.
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Felix Steinhardt

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Re: Flange distance issue

PostTue Feb 12, 2013 12:58 pm

Your Nikon AI-S lenses have hard stops at infinity, too?
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John Bauer

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Re: Flange distance issue

PostTue Feb 12, 2013 6:40 pm

this is very worrying indeed
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Kristian Lam

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Re: Flange distance issue

PostWed Feb 13, 2013 8:09 am

Hey guys

Just to let you know Phillip has also sent us some data and we are looking into this issue.

Thanks
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Cam Macduff

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Re: Flange distance issue

PostWed Feb 13, 2013 9:10 am

Yah!! Thank-you!
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danap

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Re: Flange distance issue

PostWed Feb 13, 2013 2:51 pm

BMCC owner here. I have a kind of premonition that BlackMagic Design will issue a general recall on all camera models and reinstall a THINNER Canon EF mount ring; or -alternatively ask owners to do it themselves. Your opinion?
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John Richard

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Re: Flange distance issue

PostWed Feb 13, 2013 3:03 pm

I sincerely hope that a resolution such as this is forthcoming.

The one thing that worries me though is that the early beta testers with the original sensor/glass cover did not experience infinity focus issues. Think these cinematographers were straight up and did not see this. Then after the sensor glass issues, this infinity focus issue on many lenses cropped up.

Maybe a new replacement flange would fix this too?

Just adjusted my Tokina 11-16mm/2.8 per the Christian 3-screw method move to the left (Canon) and it did improve somewhat but still not usable at 11mm on our BMCC. But when I remounted on the Canon 7D it works fine at 11mm down to 2.8 iris. Sure seems like a BMCC flange issue.
Last edited by John Richard on Wed Feb 13, 2013 4:35 pm, edited 1 time in total.
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Abobakr M. Alshiblie

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Re: Flange distance issue

PostWed Feb 13, 2013 3:28 pm

John Richard wrote:I sincerely hope that a resolution such as this is forthcoming.

The one thing that worries me though is that the early beta testers with the original sensor/glass cover did not experience infinity focus issues. Think these cinematographers were straight up and did not see this. Then after the sensor glass issues, this infinity focus issue on many lenses cropped up.


I don't think it has anything to do with the glass. Frank Glencairn, one of the early people to recieve his camera is experiencing the same issue with his Tokina 11-16mm
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Felix Steinhardt

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Re: Flange distance issue

PostWed Feb 13, 2013 3:35 pm

danap wrote:BMCC owner here. I have a kind of premonition that BlackMagic Design will issue a general recall on all camera models and reinstall a THINNER Canon EF mount ring; or -alternatively ask owners to do it themselves. Your opinion?


Second option is perfect. Please no general recall that interferes with production.
But they should stop building cameras now (!) and continue with a thinner mount.
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Jules Bushell

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Re: Flange distance issue

PostWed Feb 13, 2013 7:19 pm

I assume this issue won't occur on the MFT BMCC or with an EF adaptor on it?

Jules
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Darryl Gregory

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Re: Flange distance issue

PostThu Feb 14, 2013 3:12 am

Jules Bushell wrote:I assume this issue won't occur on the MFT BMCC or with an EF adaptor on it?

Jules


And I assume this issue should not occur at all with the EF BMCC, I had plans to buy the MFT but after this fiasco I have my doubts, and Just to clarify with Phillips findings the Zeiss 85mm f1.4. EOS mount version. Furthest focus ~70m, I may be getting 73m-75m but need more testing.
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Christian Schmeer

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Re: Flange distance issue

PostThu Feb 14, 2013 3:49 am

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.
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Scott Pultz

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Re: Flange distance issue

PostThu Feb 14, 2013 4:11 am

Christian Schmeer wrote: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.


That lens is probably not parfocal (holds focus as it zoom)

http://www.lensrentals.com/blog/2011/02 ... or-video/4
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Alexandre Hotton

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Re: Flange distance issue

PostThu Feb 14, 2013 8:57 am

Christian Schmeer wrote: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.

I have the same problem with the Canon 16-35 . + flange issue
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Darryl Gregory

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Re: Flange distance issue

PostThu Feb 14, 2013 9:26 am

I hate to get upset and complain but I have no choice this is ridiculous,
$3000 later and half my lenses can not focus @ infinity,
I can not imagine BM would release a camera without thoroughly testing
the flange distance on various lenses, it's like boring a cylinder for a new piston
and not using a micrometer.

It's just not done that way, you must use a micrometer before you bore a cylinder period!

Sadly I think I need to return my BMCC, I'll wait and see what comes in V2.
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Nilscrompton

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Re: Flange distance issue

PostThu Feb 14, 2013 9:45 am

In my case I'm prepared to navigate these 'hiccups', the benefits of this camera vastly outweigh them. I used to shoot on Canon DSLRs and I dont miss the workarounds I had to use with them. There isn't really another option for independent shooters looking for post options. For shoot to finish workflows a C100 might be smoother sailing, but it is still double the price... So the only option is back to the 5D... no thanks.
http://minifilm.co
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Darryl Gregory

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Re: Flange distance issue

PostThu Feb 14, 2013 9:54 am

nilsonium wrote:In my case I'm prepared to navigate these 'hiccups', the benefits of this camera vastly outweigh them. I used to shoot on Canon DSLRs and I dont miss the workarounds I had to use with them. There isn't really another option for independent shooters looking for post options. For shoot to finish workflows a C100 might be smoother sailing, but it is still double the price... So the only option is back to the 5D... no thanks.


I understand how your feel nilsonium,
but I have shot with plenty of cameras, I get hired as a DP, not by what cameras I own,
The fact I own several cameras some on par with.. or below the BMCC, and one that far surpasses it at 6+ times the price is not an excuse for me to keep the BMCC, Simple fact is this camera is still a BETA camera, should have never made it to market till 2014-2015.

Signs of this are obvious!
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Nilscrompton

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Re: Flange distance issue

PostThu Feb 14, 2013 11:41 am

Ah I see. Yes, if you're a working DP I can see that 'hiccups' are the last thing you want, especially if you have an existing set of lenses you're expecting it to work with. I can see your point about it being 'BETA'.

As an aspiring DP, I suppose my market is micro budget music clips, where not having to hire a camera means I get to pocket the hire fee 8-) , and as an actual editor/compositor, I was always going to be fan of the RAW options... perhaps it really is a camera by post people for post people...

Do you have any suggestions for Tokina 11-16mm replacements that aren't going to short focus? I'm sussing out the Rokinon 14mm, but I'm perplexed how to get ND to work with it without a matte box... and the Sigmas seem a bit slow...
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Darryl Gregory

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Re: Flange distance issue

PostThu Feb 14, 2013 11:50 am

I tested my friends Sigma 17-50mm and it is awesome on the BMCC
IS/OS works, The BMCC auto Focus button worked, it is sharp, color is nice, it just worked great all around.
It's Just not very fast--> f/2.8 or wide enough :|
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Bill Rich

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Re: Flange distance issue

PostThu Feb 14, 2013 2:05 pm

I am very happy with the IQ of the BMCC.. but the fact that half my EF lenses don't communicate with the camera.. Now the infinity focus issue has me concerned as well.. I have the 14mm Rokinon cine lens but it's much softer than my Sigma or Canon Lenses so I'm less likely to use it in favor of something else.. ..

I'm waiting for BMD to come up with solutions for these recent issues before I talk about returning my BMCC.. I just can't wait too long before it's too late to return it. I was so excited when I got the camera.. but then discovered that Resolve doesn't work on my computer.. now this.. I need to make up my mind soon.. Please let us know what's going on Blackmagic! I want this camera to work! but I can't spend $3K on a camera that I'm not 100% confident in..

Edit.. I just put in a request to return the camera.. what a freaking shame.. I've waited so long for it!
Bill Rich
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