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John Brawley

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Posts posted by John Brawley

  1. 8 minutes ago, Andrew Reid said:

    I can't help but feel a bit of a chill in the air.

    These are your customers you're talking to John and fellow filmmakers. ...

    You should just be honest. You are here to sell a Pocket 4K camera. You don't give a shit about what I shoot, or what I write. I am just a guy hosting your posts.

    Nope. You all aren't my customers.  I don't sell anything.  

    I thought you were professional colleagues.

    I'm not here to sell cameras.

    I'm a working cinematographer. I used to enjoy sharing what I knew.

    I do unpaid consulting work with many manufacturers, including BMD.

    Feel free to delete every single one of my posts.  You don't have to host them.  

    JB

  2. 6 hours ago, andrgl said:

    See this is why I'd like to have @Brian Caldwell reply. I was forced to study optics for a semester specifically for microscopy.

    Brian could maybe tell us what specifically changes quantitatively. Instead of just "performance".

    Can't really fathom what else would change besides the angle of refraction.

    He’s posted a few times on the BMD forum about this issue. Some others have tested his assertions as well. 

    My takeaway is that the edges are “softer” and have more aberrations with fast primes because the design isn’t optimised for the different thickness in cover glass (not made by Sony)

    https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=71899

    and

    https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=26122

    JB

     

    EDIT and actually this post and the video below it demonstrates the differences visually.  https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=26122#p162887

     

     

     

  3. 54 minutes ago, majoraxis said:

    @John Brawley - Really interesting discussion!  If you use a faster lens wide open without a speed booster will the performance change based on sensor stack thickness?  Does a manufacturer like Sony stay will the same sensor stack thinness year over year? or if Sony makes it thinner generation to generation, does performance increases generation to generation with the same native lenses?

    Thanks!

    The sensor maker doesn’t necessarily make the sensor stack. The very fact that the sensor stack thickness is consistent with BMD cameras should tell you this.  

    Wide open lenses with shorter cover glass isn’t the issue. It’s because we’re adding another optical formula in between the rear of the lens and the sensor.

    The thickness isn’t important to performance either. Obviously or we’d have noticed major problems by now !

    It changes the optics performance of what a speed booster is doing though. And THATS the issue.

    It’s not worse.  Or better. It’s just different to other MFT cameras and that means to fully optimise the optics design of the SB you have to change the formula and that makes it less optimal for other MFT cameras.  

    This is about making a correction to get the most from a lens.  

    Many cine lenses that have rear filters for example always have to have a clear filter in because the optical formula is calculated with that exact thickness of refractive index always being there, no matter if it’s clear or ND.  

    This is my “lay” understanding.  It gets reported as “non standard” MFT cover glass, but there isn’t an actual standard ! 

    Olympus and Panasonic both use a different thickness, it’s just that they’re close enough together that the same speed booster works fine for both of them. (One is 2.3mm I think and one is 2.5mm)

    They are also using OLPFs as well as being IR. BMD only have the IR filter, no OLPF.  

    This is about economics.  They don’t want to have to make a BMD specific speedbooster, they want the same MFT speedbooster to work on all MFT cameras.

     

    JB

     

  4. 1 hour ago, andrgl said:

    @Brian Caldwell

    Can we get you to weigh in on this?

    As far as I understand, filter stack thickness varies between m43 cameras, yet no m43 camera has problems focusing native lenses to infinity.

    Which leads me to believe the camera manufacturer offset the distance of the mount to account for their filter stack to prevent this issue from ever occuring.

    It’s not to do with getting focus at infinity at all.

    its about optimising performance with very fast lenses when shooting wide open. 

    Previously it meant making a specifically optimised BMD SB variant to account for the different IR cover glass thickness. 

    You can still use a regular SB and it will still hit infinity. It’s just less optimised to work with faster than F2 lenses. 

    JB

  5. 2 hours ago, Snuff said:

    The author of this video "Bubble Gum" answered that he didn't use any IR CUT filters. Does it mean that there is not IR pollution in the BMP4K and we don't need IR CUT filters anymore?

     

    The Hoya PRO filters are in effect IR cut filters. I’m the same way that Firecrest, Nisi and Lee ND filters aren’t designated IR cut filters but work that way. 

    The sensor is covered by the same low IR cut glass as every other BMD camera is. 

    A regular ND filter will show IR pollution in the right circumstances.

    JB

  6. 5 minutes ago, Anaconda_ said:

    Actually, he didn't. According to the files that we can now download, 'Close Up Night' was 192 deg and 'Walking Day' was 215 deg.

    @John Brawley do you know / remember if that's correct? 

    Also, that's what I thought about the audio.

    I think maybe 192 is right because we had some flicker from practicals but I don't think 215 sounds right for day.

    JB

  7. 8 minutes ago, Anaconda_ said:

    If these are camera files, why is the 'Nature' footage, which was supposedly shot in RAW actually a ProRes file? 

    I also notice there's no audio on the clips. Were the mics turned off or have these files been adjusted for the downloads?

    Grant made so many comments about the built in audio, but has given little info away on it.

    It doesn't really matter, but I'm just curious ?

    I had the audio in camera turned off in mine. You don't want to listen to me directing the cast and "handling" the camera.

    JB

  8. 49 minutes ago, Jonesy Jones said:

    Don't know if everyone has seen this, but BM is allowing us to download the files for ALL of the sample videos posted. Before I found this I had only seen the download feature enabled for one of John's videos. But they can all be downloaded here. - https://www.blackmagicdesign.com/products/blackmagicpocketcinemacamera/gallery

    Let's see what you colourists are made of.

    JB

  9. Leslie.

    You've admitted you've not watched any footage and have no production experience.  You're speaking to an audience here in this thread that has a either a great deal of experience, or lot more experience than you yourself and who have actually bothered to read a little more before posting to an audience of like minded individuals.

    Consider researching a little more thoroughly at least before throwing some handgrenades of questions like the ones you dropped in your previous post. 

    I don't even know where to begin if I have to explain why it can take much longer to grade a shot than to shoot it. 

    Learning is great, and knowledge can be had here.  This is a very helpful community but you have to put in a little effort rather than it being spoon fed to you.

    JB

  10. 2 hours ago, Myownfriend said:

    This is actually surprising to hear. From what I can tell, the Pocket 4K is a little larger than two Micro's side by side, but I guess after rigging up the Micro it very quickly loses it's size advantage.

    Actually this reminds me, there's a guy who's a BMD evangelist whose name escapes me at the moment but he's an older gentleman, who was interviewed about the Pocket 4K and said that the final version will be a little lighter (which we knew was the case with the whole carbon fiber thing) but also slightly smaller. Do you know if there's any truth to the final version being slightly smaller or did he misspeak?

    It's the same size.

    Here's some examples of scenarios for me where using a micro that will be replaced by a p4K once I can get one.

    JB

     

     

    TR-103_BTSR_GD0010.JPG

    TR-103_BTSR_GD0015.JPG

    TR-105_BTS4_GD0016.JPG

    2 hours ago, Jim Giberti said:

    Really great to read all of this John.

    And I'm really glad you feel the way you do about Gen 4 and specifically extended video mode.

    Really looking forward to producing with both.

    Did you use the new Gen 4 LUT for viewing? And if so, how accurate was it?

     

    Tanx

    Yes I've been on GEN 4 for a while with the Ursa's and of course the P4K and use them for monitoring.  It's VERY hard to go back to using VIDEO.

    JB

  11. 2 hours ago, Ki Rin said:

    Not really sure why I'm getting downvoted for this.. .I understand that for some people its an unimportant feature in a camera like this. 
    I'm just saying for me personally, its the only thing stopping it being a pretty perfect camera for me. Still not a deal breaker by any means, but it would be great to have it, in my opinion. 
    What's wrong with that?

     

    Because you said “if only”

    IBIS makes it very hard to cool the sensor and it’s much harder to clock out the sensor at faster rates if it’s not cooled. 

    JB

  12. Speaking as someone who’s a long time user of the Olympus 4/3 (anyone remember that format??) and then micro 4/3 format.

    I own many 4/3 and m4/3 lenses from Olympus, Panasonic and others (Veydra, SLR Magic, Voigtlander)

    Generally speaking Olympus m4/3 lenses are better corrected optically. Panny tend to rely more heavily on in-camera / post correction.  

    Olympus also OEM many lenses for others. You’d be surprised what major brands have lenses that are made by Olympus. Optics have always been their primary strength. (They are absolute leaders in other fields like medical where they have near monolopoly market share of endoscopes etc).

    Olympus are a really interesting company, very innovative. They were the first to do live view in a stills camera. First to have an ultrasonic cleaning of the sensor. And of course their IBIS has always been the best along with weatherproofing.

    In the past few years I have been consulting with Olympus on improving their product and features to appeal to more cinematographers. These things typically take time to filter though their product development cycle. 

    The Pro primes are actually beautiful lenses. And they’re great for cinematography.  Hard stops on focus for example.  BMD asked me to shoot with the Olympus primes to show what could be done with inexpensive native 4/3 lenses and they do not disappoint. 

    JB

  13. 9 minutes ago, noplz said:

    Is it weird that I'm seriously considering trading my NX1 for one of these? Having played with one in the store the ergonomics are somewhat similar. Of course the advanced photo features I will probably never ever use but the combo of good Olympus color SOOC, amazing stabilization, over sampled 4k with a decent codec, and a non-dead lens system is really tempting. The only thing giving me pause is that the EM-5 III will likely have all of that as well in a smaller, cheaper package. And since I already traded my NX500 for a GX85 it seems like the logical next step.

     

    P.S. If anybody has pull with Olympus please ask them to axe the 29 minute video recording limit for non-EU markets. Many people don't care but for those of us that film long static events (e.g. lectures) it is a major annoyance.

    It’s not an Olympus rule. It’s an EU regulation to do with import duties. 

    JB

  14. On 8/23/2018 at 8:27 PM, BenEricson said:

    Looks great. It's kinda crazy that BM didn't put a IR cut filter in the original pocket. The camera is not very usable without, but amazing with.

    There is an IR cut filter in the sensor cover glass.

    Its about how aggressive or mild you want it to be. 

    JB

  15. 5 hours ago, webrunner5 said:

    From Arri website.

    "The Dual Gain Architecture simultaneously provides two separate read-out paths from each pixel with different amplification. The first path contains the regular, highly amplified signal. The second path contains a signal with lower amplification, to capture the information that is clipped in the first path. Both paths feed into the camera's A/D converters, delivering a 14 bit image for each path. These images are then combined into a single 16 bit high dynamic range image".

     

    My mistake.

    Two 14 bit image streams, not 12 bit with regard to Arri.

    BMD are the same with dual gain sensors, there are two 11 bit streams that are processed and merged into a single 16 bit lin image.

    JB

  16. 7 hours ago, Myownfriend said:

    Sure it's raw. If my understanding of the Ursa Mini Pro's sensor is up to snuff, it's taking two 11-bit values from two different gain circuits or something then averages them into a 14 bit values. Those values are then logarithmically stored as 12-bit values and THAT becomes the output DNG. Pixel binning would be a form of averaging as well so if the former is acceptable RAW then so is the latter.

    Actually two 11 bit values turns into a 22 bit value, which is then processed as 16bit lin internally, not 14bit. It’s then log encoded as a 12bit once it’s encoded into a DNG or ProRes. 

    Alexa is the same, but two 12bit values turned into a 24bit value then down to 16bit. 

    I’ve long felt bit depth is the most important part of the digital imaging chain, not resolution.

    JB

  17. Edge sharpness. 

    First we should look at the imaging chain. Is there an OLPF ? The absence of one will mean a sharper edge but the increased chance of false colour moire. 

    Sharpness settings in camera menus aren’t compare-able I would have thought camera to camera. 

    Seems like if edge sharpness is what’s being examined then you’re really talking about “detail” and “coring”. 

    These are both setting that are in video encoded products but are not in BMDs camera video processing (except for the broadcast cameras) 

    These are post applied video processing of signals that tries to improve edge sharpness.  Some cameras allow the user to adjust these settings.  Some bake them in without any user adjustment.

    JB

     

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