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AndrewM

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  1. Like
    AndrewM got a reaction from maxotics in Are S-LOGS More Destructive Than They're Worth?   
    So again, maybe I'm missing things, but let me try and focus (for myself, mainly) on what is at issue here... There are a bunch of questions, and I think different people are answering different ones. I'm going to simplify by saying "rec709 scene" to mean a scene with no more dynamic range and colors variation than can be captured by the rec709 spec. In other words, a scene that looks like pointing your camera at your tv or monitor.
    Question 1: How often in real world situations do you find yourself shooting a rec709 scene?
    My answer: in a controlled studio environment with expert lighting people - yes. Outside, on a really overcast day - maybe. Inside or outside, in "normal" conditions - never.
    Question 2: If confronted with a rec709 scene, should you shoot with a rec709 gamma?
    My answer(s): yes, if you are really good at your job, because you will get the maximum, densest information possible given your codec etc. No, if you are in a rush, or less than 100% confident in your technical skills, or if you just want to be careful because there are a lot of other people working that day whose work product (or wedding...) depends on you doing things right with no reshoots. If the dynamic range I encode exactly matches the dynamic range of my scene, and I misexpose at all, then I will have clipping at one end or the other. And (in my opinion) clipping is way worse than faint banding. Still photographers, even really good ones, bracket for a reason. Or have gear and raw formats good enough that they have sufficient margin of error so they don't have to.
    Question 3: If confronted with a rec709 scene and I shoot with a wider-dynamic range codec, will I end up with a "worse" image?
    My answer: duh yes. In some sense, I must. I am spending bits to encode details that don't exist in the image - lots of zeros. I am spreading the ability to discriminate much more thinly over the part of the scene where all the action is. That, mathematically, must have consequences.
    Question 4: How much worse?
    Worse mathematically does not necessarily mean worse visually - that's why lossy compression, on which the entire existence of digital video depends. And "worse in the real world" is not the same as "visually detectable in a scene with continuous color gradients not found in nature."
    I think the goal of the OP is admirable - to try and quantify this. I just see so many variables (per camera, per camera setting, per what differences actually matter) that the task seems next to impossible.
    Question 5: Is there something about "consumer" cams (hybrids, still cameras that also take video) vs "professional" cams (dedicated video cameras) that makes a difference here, relevant to the merits of log?
    My answer(s): yes and no. If we are talking sensors, there is lots of variation and a lot of reasons why a dedicated video chip might be better, but the bottom line is that any consumer camera that is capable of taking raw images, even sucky raw images, is capable of capturing way, way, way more information than is available in rec709. There haven't been rec709 limited sensors in 40 years.
    If we are talking codecs and data limits, then of course. The more data you throw at the scene (given equally efficient codecs) the more discrimination you get. Pro cameras often throw more data at the problem. So the big question is: given current codecs and processing limits, do consumer cams have the data rates to support log shooting? Which gets us to...
    Question 6: Should we be shooting log on current 8 bit cameras if we are delivering rec709?
    My answer: depends on the camera, the videographer, the colorist, and the project. If people deliver results that are better than otherwise available, then the answer is yes (for that setup and those skills) and if they don't, the answer is no.
  2. Like
    AndrewM reacted to tomekk in Sony Will Announce the A6500   
    There is also a third model which I think Sony has taken (it's also quite a new approach). Don't you think Sony delivers features but a lot of the time they're not 100% reliable like on Canikons? They're unreliable to the point that some people after initial OHs and WOWs switch back. The third model is based around Lean startup method in which you intentionally release lower quality products in order to improve them later on.(https://en.wikipedia.org/wiki/Lean_startup). The idea is to get a "good enough" product on the market ASAP and improve it over time (https://en.wikipedia.org/wiki/Lean_startup#Minimum_viable_product). This way you can release cutting edge technologies earlier and more often, cut the costs (less testing time etc) and get feedback from customers earlier. The downsides we all know, don't we ;)? We're all unpaid beta testers all the time in a way. There is also something called split testing in which "different versions of a product are offered to customers at the same time" - sounds familiar, doesn't it? 
    It'll be interesting to see which model will come out first in the end, though!
  3. Like
    AndrewM reacted to M Carter in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    I've been really impressed with season two of "The Leftovers". Overall pretty impeccable filmed. They do a lot of handheld and occasionally miss a focus pull, but it works with the aesthetic.
    However - night scenes with a fairly openDOF - you can really see the soft filters in the bokeh. Watch the birthday party scene early in season 1 - every party light has a grid of black dots. Stuff my mrs. doesn't notice, but man - really surprising to see something so odd. I've caught it in season two every here and there, but nothing like that party scene.
  4. Like
    AndrewM reacted to Axel in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    This thread sums up my own observations. I do believe that too perfectly lit, framed and colored images can get in the way of the story. Did you see Netflix' The Killing, first two seasons? It's Seattle, and it's raining most of the time. The light is grey. Very often, particularly in long shots, the view is obstructed by sometimes unindentifiable foreground objects (or the said rain). I saw a book recently on an american photographer (forgot the name unfortunately, I thought it was Abel Leibner, something similar, but I got no hits on Google, does anyone know?). His photos also feature the main motif framed by a lot of obstructions, distortions or as faint reflections. Very interesting style, the opposite of Broadchurch season 2. You intentionally place distractions in the frame and let the viewer find the most interesting detail (which is the action of the characters always anyway).
    In the first episode of Fargo season 2, I liked the photography, but it doesn't seem to be good style, because now I just see it as decorative, and it distracts me. Maybe though that only camera nerds like us notice these things ...
  5. Like
    AndrewM reacted to Fritz Pierre in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    If DOF is overused, and I think this is more typical of the small sensor camcorders like the HVX or shooting on DSLR's or M4/3 cams, in an effort to hit one of the several "Holy Grails" of the filmic look (hate that phrase), to my eye it starts looking ridiculous. The reality is, if you were to shoot a feature in this way, it would either be mostly out of focus, or cost a fortune!...Used to shift attention in small dosages it has its place, but when I'm watching anything, the human eye is still the standard to aspire to and too much of anything else feels forced...in the same way that I don't want to "see" the acting, I don't want to see the presence of the camera...only the story...does not mean I did not like the washed out bleached look of 3 Kings...it made me feel the blinding light and heat of the desert...it served a purpose...
    @Andrew M...great thread and important observation!!!
  6. Like
    AndrewM reacted to Bold in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    If you crank the dial to 11 and leave it there, it loses its meaning/impact.  Nothing wrong with using color saturation judiciously, but its ever-presence in season 2 pulls me out of the story. Not so much that I won't stop watching, but enough that I'll complain about it 
  7. Like
    AndrewM reacted to Liam in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    Sherlock has a ton of shallow depth of field. Don't know if it has really annoyed me, but it's noticeable. while the show was still decent I didn't mind it  . the shallow depth of field and constant camera movement in Scandal is just hilarious. Always weird to see what works and what doesn't. Some of my favorite shows have "terrible" image quality (Peep Show, The League, It's Always Sunny). Fincher's Gone Girl looks pretty standard and nice, nothing to write home about for cinematography, but I like the grade, even though.. it's pretty much all green and underexposed. I enjoy a bit of undersaturation and deeper depth of field.
  8. Like
    AndrewM reacted to Hans Punk in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    Depends what eyes you are watching with, a general 'non technical' viewer may not be very articulate in expressing the technical proficiencies or deficiencies of a production, they will simply like or dislike the viewing experience - Be immersed or 'taken out' of the show/film by the presentation experience. General audiences do not care (nor should they) about what camera,format, post production process was used for a TV or film production, for them it should support and serve the story,mood and vision of director and DP and to all intensive purposes be nearly invisible to them.
    For example, Most audiences don't even realize that they have motion smoothing on thier TV's as a default setting in some cases. But audiences are more and more technically savvy now to what higher end productions 'should' look like - they have an expectation of quality now with high-end TV shows that often rivals film production standards. 
    It is often true that 'style over content' can be seen - often in TV, less so in film - where generally time and budget is smaller so less time is available to perfect everything from art department to lighting, making a cheaper emulation of bigger budget shows or films fall short of the results of weeks or months of pre/post production time. There are many reasons why films take so long to make, when a TV show employs similar aesthetics they sometimes fall short and audiences can tell. This is often a trap I see happen in low budget film - when trying to mimic the style of a bigger budget production but without being able to see why it works. 'Greengrass shoots shaky handheld?...cool, let's shoot our entire film handheld...even for the dialogue scenes'! 
    Broadchurch is a show that employed a great deal of real locations in the South west of England, shooting in summer time - where it can be very visually attractive.
    richg101 on this forum lives in one of the seaside towns (Clevedon) where they shot a decent portion of that show, and from his stills and videos from over the years you can see how nice it can be made to look. 'The Remains of the Day' and 'Never Let Me Go' are notable movies shot there.
    Production value on screen are instant as soon as you shoot in interesting locations, Broadchurch was fairly unique in that regard for a UK drama often only augmenting natural light to get filmic results. Being relatively local and knowing people 'in the biz' who worked on that show, it's very clear about the constant battle with turnaround times for these shows have so it comes as little surprise that the final 'look' can be compromised to those who may be more opinionated on aesthetic values of film or TV production.
    Often the grade is where things get better or broken, in TV it is often a limiting medium to go too crazy - as there are still legal limits to broadcast and people will complain that an image is too dark for example, even when it is an artistic choice for a noir feel....people want mediocre which is why most dramas (at least UK ones) look like they are graded in the same bay session as the commercials either side of the show - often looking too sickly saturated, or too flat and bland to not risk little 86 year old dorothy in Aberdeen to complain about not being able to see what's going on in a moody drama.
    Saying that (and being a bit biased) UK drama can have the most diverse and interesting looks when it is allowed to. Channel 4's 'Black Mirror' / 'Utopia' and similar shows are visually outstanding, especially compared to primetime 'Broadchurch' type shows that always have the pressure of broader appeal and trying to employ 'commercial' styles that does not always compliment story or theme.
  9. Like
    AndrewM reacted to kaylee in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    fascinating
    i did this, and i gotta say, i found the look of the show – including all aspects of art direction which appear on screen – to be completely forgettable and boring
    i watched several different clips from season one and two and my general critique is that color and lighting are not being used dramatically in terms of storytelling in a lot of the shots
    dont get me wrong, its clearly technically sound, but its boring
    but boring in a very pretty, attractive way, which forces you to look at it more than through it – like a window. and this is a disconnect in terms of immersion and suspension of disbelief – storytelling
    in general it also looks too much like crappy-poo reality, which we all know too well
    so my assessment is that you would like this show more if color was used in a more meaningful way
    let me blow your mind with an analogy:

    which is better? why? more here
     
  10. Like
    AndrewM got a reaction from Liam in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    The second season of Broadchurch is up on Netflix, so I have been watching. And after a while, I found myself thinking "what beautiful images, what talented cinematography, what great color." No matter what you think of the content of the show, it is made by incredibly competent people. Apart from some annoying, intentionally-jerky handheld work, there is great composition, some amazing tracking work and focus pulls, great control of light and beautiful colors for people and landscapes alike. And the lenses are just beautiful too - there is a lot of shallow depth of field work, and the backgrounds are soft and creamy and not distracting. Generally, the images just "pop" in all aspects. So I googled out of curiosity, and it was shot on Alexa.
    But after a while longer, I began to feel... oppressed by all the imagery. And that is what I wanted to start the topic about - the aesthetics. Broadchurch has all the things that people on this forum often talk about positively, and that I would take as positives too - the intelligent and creative use of shallow depth of field that comes with big sensors, color that is vivid yet "real," and an organic "film-like" image. You won't see any clipping or noise on this show...
    If you haven't seen it, you can pull up a few minutes online and see what I mean. It can be any few minutes.
    I am trying to reflect on this oppressiveness I am feeling, because it is making it hard for me to watch. And I am wondering if anyone sees/feels the same. The best theory I have is this - on color, it is like living in an eternal "golden hour." The colors are absolutely lovely, but you wish sometimes they would go away - they are asking too much of you in their loveliness. On the shallow depth of field: the work is incredibly proficient, but sometimes you wish you could just see the scene and decide where to look, and not have your attention dragged around the scene by the decisions of the director and cinematographer. Again, you wish it would go away and ask less of you.
    Maybe it is just me, and I am just odd. But I am wondering if anyone else has had this feeling, on this or some other film and their aesthetics. It is great, in many many ways, but in some way (for me, at least) it is "too" great. I would aspire in my dreams to produce images with a fraction of the quality of those in Broadchurch, but I find myself being distracted by them and not wanting to watch.
  11. Like
    AndrewM got a reaction from Bold in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    The second season of Broadchurch is up on Netflix, so I have been watching. And after a while, I found myself thinking "what beautiful images, what talented cinematography, what great color." No matter what you think of the content of the show, it is made by incredibly competent people. Apart from some annoying, intentionally-jerky handheld work, there is great composition, some amazing tracking work and focus pulls, great control of light and beautiful colors for people and landscapes alike. And the lenses are just beautiful too - there is a lot of shallow depth of field work, and the backgrounds are soft and creamy and not distracting. Generally, the images just "pop" in all aspects. So I googled out of curiosity, and it was shot on Alexa.
    But after a while longer, I began to feel... oppressed by all the imagery. And that is what I wanted to start the topic about - the aesthetics. Broadchurch has all the things that people on this forum often talk about positively, and that I would take as positives too - the intelligent and creative use of shallow depth of field that comes with big sensors, color that is vivid yet "real," and an organic "film-like" image. You won't see any clipping or noise on this show...
    If you haven't seen it, you can pull up a few minutes online and see what I mean. It can be any few minutes.
    I am trying to reflect on this oppressiveness I am feeling, because it is making it hard for me to watch. And I am wondering if anyone sees/feels the same. The best theory I have is this - on color, it is like living in an eternal "golden hour." The colors are absolutely lovely, but you wish sometimes they would go away - they are asking too much of you in their loveliness. On the shallow depth of field: the work is incredibly proficient, but sometimes you wish you could just see the scene and decide where to look, and not have your attention dragged around the scene by the decisions of the director and cinematographer. Again, you wish it would go away and ask less of you.
    Maybe it is just me, and I am just odd. But I am wondering if anyone else has had this feeling, on this or some other film and their aesthetics. It is great, in many many ways, but in some way (for me, at least) it is "too" great. I would aspire in my dreams to produce images with a fraction of the quality of those in Broadchurch, but I find myself being distracted by them and not wanting to watch.
  12. Like
    AndrewM reacted to Jimbo in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    A fascinating and insightful thought. I haven't seen much of Broadchurch myself but I think I had a similar experience when watching Tree of Life. The imagery is mind-blowing, delivered through artisan cinematography, but I actually found it exhausting to watch because every frame demanded your attention. It was also a tiring mix of fluid shots and sharp cuts.
    I found its portrayal of life, especially the growing up scenes with the brothers, wholly truthful and evocative in places, but the continual movement of the camera and breaking from abstract to real was overwhelming at times. I would liken the experience to reading a literary novel or visiting an art gallery. You can gobble up the craftsmanship of each paragraph and painting for only so long before you get art indigestion.
    I watch such films and read such books to learn, but when the art overwhelms, or is stronger than, the story then I start to lose interest, nay, get angry. This may be the problem with Broadchurch, that the visual art is drowning the story, which is made all the more difficult for someone like yourself who is tuned to spot beautiful cinematography.
  13. Like
    AndrewM got a reaction from Jimbo in Beautiful color or oppressive color? "Broadchurch," Arri and aesthetics.   
    The second season of Broadchurch is up on Netflix, so I have been watching. And after a while, I found myself thinking "what beautiful images, what talented cinematography, what great color." No matter what you think of the content of the show, it is made by incredibly competent people. Apart from some annoying, intentionally-jerky handheld work, there is great composition, some amazing tracking work and focus pulls, great control of light and beautiful colors for people and landscapes alike. And the lenses are just beautiful too - there is a lot of shallow depth of field work, and the backgrounds are soft and creamy and not distracting. Generally, the images just "pop" in all aspects. So I googled out of curiosity, and it was shot on Alexa.
    But after a while longer, I began to feel... oppressed by all the imagery. And that is what I wanted to start the topic about - the aesthetics. Broadchurch has all the things that people on this forum often talk about positively, and that I would take as positives too - the intelligent and creative use of shallow depth of field that comes with big sensors, color that is vivid yet "real," and an organic "film-like" image. You won't see any clipping or noise on this show...
    If you haven't seen it, you can pull up a few minutes online and see what I mean. It can be any few minutes.
    I am trying to reflect on this oppressiveness I am feeling, because it is making it hard for me to watch. And I am wondering if anyone sees/feels the same. The best theory I have is this - on color, it is like living in an eternal "golden hour." The colors are absolutely lovely, but you wish sometimes they would go away - they are asking too much of you in their loveliness. On the shallow depth of field: the work is incredibly proficient, but sometimes you wish you could just see the scene and decide where to look, and not have your attention dragged around the scene by the decisions of the director and cinematographer. Again, you wish it would go away and ask less of you.
    Maybe it is just me, and I am just odd. But I am wondering if anyone else has had this feeling, on this or some other film and their aesthetics. It is great, in many many ways, but in some way (for me, at least) it is "too" great. I would aspire in my dreams to produce images with a fraction of the quality of those in Broadchurch, but I find myself being distracted by them and not wanting to watch.
  14. Like
    AndrewM got a reaction from Xavier Plagaro Mussard in Sony A7II gets in-body 5 axis stabilisation and S-LOG 2   
    If the stabilization works well in video, then there are all sorts a flow-on benefits. Compression will work better (vertical and horizontal movements "suit" the algorithms, but roll really screws with it, and fewer small changes to deal with means more data going to things that matter) and rolling shutter effects that delay and spread out camera movements and make things swirl will be reduced. Frankly, the second is really big for me - I can't watch go pro footage most of the time because of the combination of rolling shutter and lots of camera movement is completely disorienting.
  15. Like
    AndrewM reacted to Quirky in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    Interesting. I can't help but wondering if this new tech will become the one to replace the Bayer one eventually, though. I'm no expert, but my gut feeling tells me that the next 'industry standard' tech, should there ever be one in the future, should be something simpler, electronic or not. I bet there will soon be other rivalling technologies out later on, at least on paper.
    I also wonder if this will just replace one set of digital artefacts (rolling shutter, interpolation artefacts) with all new ones. Oh well, s'pose we'll see, eventually. Anyway, getting a global shutter as a bonus sounds good to me.
     
    Meanwhile, what a nice 'leak,' whether it was deliberate or not. It'll be an abundant source for nerdytainment, and it'll keep the hardcore geeks busy for weeks, way before any actual device with the actual tech hits the shelves. As soon as someone introduces the obligatory and inevitable N-word and C-word into the debate, this thread will no doubt have 17+ pages by the time CES and CP+ take place in early 2015.  
     
    I'm not bashing no-nonsense comments like those by AndrewM here, they are interesting reading per se.
    Just predicting the likely near future before we see the actual sensor in an actual camera, in a not too serious fashion.
    Carry on.  ;)
  16. Like
    AndrewM got a reaction from maxotics in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    I think the Foveon/Sigma problem is probably a mix of (1) silicon being a pretty lousy (and probabilistic) color filter, thus providing "information" that requires an awful lot of massaging to make "real" color, (2) trying to pull information from three distinct layers of a chip and (3) Sigma being a small company and not really an electronics company. So they probably don't have cutting-edge processing hardware, or custom hardware, or optimized code and algorithms. And there are just differences in the details of everybody's solutions that don't seem intrinsic to basic technology - Panasonic, for instance, seems to have lower power/lower heat 4K processing than Sony right now, for whatever reason. I am a little puzzled why the Sigmas aren't better.
     
    I think, if we are understanding the Sony imager right, the first issue is how good and how quick the electronically-changing color filter is. If it is good (quick and color accurate), then all you have to do theoretically is pull the numbers from each sensor and sum them individually for each color pass. You could do that locally for each pixel with very simple hardware in essentially no time - you just have an add-buffer. Then you have to get all the numbers off the sensor into the rest of the chip, but that only has to happen once a frame. And you don't have to do that quickly, or worry about rolling shutter, because the moment of exposure is controlled at the pixel. Global shutter is free.
     
    The other issue is sensitivity. If we are right, then each frame is a lot of exposures in each color added up. Short exposure means less light, even if the pixels are three times the size because no Bayer.
     
    My guess is that there will be a trade-off. At low light, you can have low noise/good sensitivity (by having long individual color exposures and summing fewer of them) but then you will have problems with temporal aliasing of color (which you might be able to deal with in processing but at a loss of resolution). Or you can have good temporal resolution by having more, shorter exposures, at the cost of greater noise/lesser sensitivity. Low light with lots of motion is going to be the worst case for this technology, if I am understanding it right.
  17. Like
    AndrewM reacted to maxotics in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    Hi Andrew, as you know, Sigma cameras take seemingly forever to write RAW data.  I assume it's because, as Benjamin pointed out, there is a lot of heavy math going into the interpretation of color readings.  More evidence of the difficult math is that Adobe has never created a RAW reader for these files and the Sigma software is notoriously slow and buggy processing these files.
     
    The newer Sigma cameras use a high resolution top (blue?) layer to make a better compromise between resolution and color.  I tried one of the new camera, still very slow.
     
    So the question is, has Sony figured out an electronic or mathematical way around Foveon (vertical color sampling) problems.  I somewhat doubt it.  Or are they using high resolution, over-sampling and the less critical nature of video color to sacrifice color accuracy for aliasing free video at high frame rates?
     
    Like the A7S, which isn't anything new, but a chip made the way a low-light videographer would make it, my belief is that Sony hasn't developed a new technology here.  They're just making chips that will do one thing well, along the lines of what Sunyata said, (as you know, as nice as thte a7S is, it loses dynamic range at low ISO).
     
    Thoughts?
  18. Like
    AndrewM got a reaction from maxotics in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    On how the Foveon sensor works - you are both right. It does have multiple sensels for the different colors, but they are stacked on top of each other vertically. And it does have color filters, and it doesn't have color filters. Essentially, it uses the silicon as a filter - different frequencies of light penetrate to different depths, so end up in different sensels.
     
    On the new Sony sensor - we are all guessing, but if it is taking sequential pictures in different colors, then what you are doing is swapping spatial chroma aliasing for temporal chroma aliasing - if objects are moving, then a single object will exhibit weird uneven color smearing that would have to corrected in software, which will cost you resolution. That is why I think you are seeing the insane frame rates. If you were shooting 30p with 1/60 shutter, and it did 1/180 second red, then 1/180 green, then 1/180 blue,  anything that has changed position in 1/180 second is going to cause real problems. But if, in 1/60 of a second, it shoots r-b-g-r-b-g-r-b-g-r-b-g... and combines the exposures, the problem goes away to a large extent.
     
    That would be really exciting. It would also allow you to do some really, really cool things to deal with temporal aliasing and to give more pleasing motion blur - you could assign lower weights to the exposures at the beginning  and end of the broader exposure interval.
     
    see http://www.red.com/learn/red-101/cinema-temporal-aliasing
  19. Like
    AndrewM reacted to Nikkor in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    Oh great link, finally I understand why motion blur sucks so much on my camera, I thought I was making this up.
  20. Like
    AndrewM got a reaction from Nikkor in Huge Sony sensor advance heralds amazing video features - 6K, and 1080p at up to 16,000fps   
    On how the Foveon sensor works - you are both right. It does have multiple sensels for the different colors, but they are stacked on top of each other vertically. And it does have color filters, and it doesn't have color filters. Essentially, it uses the silicon as a filter - different frequencies of light penetrate to different depths, so end up in different sensels.
     
    On the new Sony sensor - we are all guessing, but if it is taking sequential pictures in different colors, then what you are doing is swapping spatial chroma aliasing for temporal chroma aliasing - if objects are moving, then a single object will exhibit weird uneven color smearing that would have to corrected in software, which will cost you resolution. That is why I think you are seeing the insane frame rates. If you were shooting 30p with 1/60 shutter, and it did 1/180 second red, then 1/180 green, then 1/180 blue,  anything that has changed position in 1/180 second is going to cause real problems. But if, in 1/60 of a second, it shoots r-b-g-r-b-g-r-b-g-r-b-g... and combines the exposures, the problem goes away to a large extent.
     
    That would be really exciting. It would also allow you to do some really, really cool things to deal with temporal aliasing and to give more pleasing motion blur - you could assign lower weights to the exposures at the beginning  and end of the broader exposure interval.
     
    see http://www.red.com/learn/red-101/cinema-temporal-aliasing
  21. Like
    AndrewM reacted to Viet Bach Bui in I purchased a GH4 after realizing that the FF advantage is a myth   
    That is quite a strange argument you have put forth, jcs. It is the same as saying there is no portability disadvantage in carrying camera A which is four times as big as camera B since you can put it in the hands of someone four times as big. The previous statement is mathematically correct but what are the odds of there being someone that huge?

    The keyword here is availability.

    The situation is the same with focal reducers. Mathematically, FF sensors can benefit from focal reducers too. But nobody consider this possibility an advantage of FF, why? Because the Medium Format or whatever type of lens big enough for FF focal reducers aren't easy to come by.

    So both the FF sensors' size advantage and the mirrorless crop sensors' focal reduction advantage all come down to availability.
  22. Like
    AndrewM reacted to JohnBarlow in I purchased a GH4 after realizing that the FF advantage is a myth   
    I can buy a nice zebra Zeiss Jena Tessar 2.8/50 for 10 quid off ebay.
     
    I can buy (indeed I own) a 1.4/24mm Nikon G for 1400 quid...
     
    do the math ;)
  23. Like
    AndrewM reacted to Jacek in I purchased a GH4 after realizing that the FF advantage is a myth   
    And just look at lenses:
    - FF 50mm/1.8 is 10x cheaper than Voigtlander 25mm/0.95..
    - FF different primes from 20/1.8 to 100/1.8 are sooo cheap (m43 equiv. 10/1 to 50/1) compared to many even weaker m43 lenses.
  24. Like
    AndrewM got a reaction from Jacek in Must watch video on full frame vs crop cameras. "Full frame look" covered.   
    There is a lot of apparent disagreement here but not much actual disagreement, I think. Is this a fair summary?
     
    If I am buying a camera BODY, there are some numbers that I should know:
            - sensor size
            - pixel count
    Now all other things being equal more pixels is nice (up to a point), but as Andrew points out at the beginning of every camera report, more pixels on a smaller sensor probably means worse pixels all other things being equal. But bottom line is that, especially for video, we have more pixels than we need. Really, it is PIXEL SIZE, which is derived from the above two numbers (roughly - Andrew's point about global shutter circuitry and other technologies like backside illumination must be taken into account) that matters more.
     
    However, all other things are almost never equal. So if we want to know how good the actual image is, everything is in the details. If I want to know the details, then I rely on review sites that take pictures under carefully controlled situations with the best possible lenses, look at how ISO 800 pics on different bodies compare, in terms of noise and resolution and so on. If there is a fudge factor in ISO, as the OP video claims, it will show up in the quality of the images at this point, so this does not concern me. Crop cameras should look worse by the factor he claims, and if so then... they will look worse, and we will all be able to tell.
     
    Now what if I am buying camera LENSES?
     
    First, we all know that there are enormous variations in lens quality - both in technical quality (MTF etc) and in aesthetic quality. Put that aside for a moment and assume all these things are equal. A lens can be described by three numbers (ignoring zoom, minimum focus, etc):
            - focal length
            - maximum aperture
            - image circle
     
    If I have my camera body already, then I have to make sure I buy lenses with a big enough image circle. If I have a full-frame body and I buy APS-C only lenses, I am going to be really disappointed by what I see, and will be using crop mode all the time and might as well have bought an APS-C camera. But I can put a larger image circle lens on a smaller sensor body (assuming I can physically attach it) and it will work fine, giving me images (again, all other things being equal) equivalent to a crop of the larger sensor body the lens was intended for. Of course, because of the crop, I may need to reframe for the same image, and because of that, depth of field and perspective will not be the same. By multiplying the focal length by the crop factor, I know how much I need to reframe for the same image (or conversely, I know which (different focal length) lens to chose so I don't have to reframe).
     
    Ok. Now let's talk about about what you get for your money. Suppose I am comparing two lenses that will render the same field of view on their native sensor size and roughly equivalent "quality" - say, a 50mm f/2.8 full-frame and a 25mm f/2.8 m43. While similar in many, many ways, the fundamental difference is that that the full-frame lens renders a larger image circle, which means that it is a more complex piece of engineering - it maintains an adequate image over a 4x larger area. That means more glass (and a heavier lens), tighter tolerances etc. It is much harder to keep that wide aperture and still resolve over that large image circle. Also, if shallow depth of field is your thing, you are not going to get as shallow with the m43 on native body.
     
    If I put that full-frame lens on a crop body it will work fine, but I am wasting an awful lot of engineering by doing so, because much of the image circle is just being ignored. Also, as Andrew points out, I may lose an awful lot of the character of the lens, which comes from its fall-off, distortions, etc.. But this may not worry me.
     
    The magic of the speedbooster is that it takes all the engineering, all the character, of the larger-format lens and squeezes it down to fit onto a smaller sensor, so you are not just throwing that away. It means you get the lens as it would be on the larger sensor.
     
    Now here is the part where I agree with the video that started all this. If you look at the lenses and their prices, full-frame lenses look like much better value. That 50mm f2.8 FF and that 25mm f2.8 m43 cost close to the same, but if you think about the job they are doing, the full frame lens is way more impressive. (It is also way heavier (because of the job it is doing)). And on a native body, it will do things the other won't, like a shallower depth of field. If that is what matters to me, then yes, I need a 25mm f1.4 native m43 lens. If that doesn't matter to me, and if other things matter more (like size) then I may not care about the full frame comparison.
     
    I'm looking at getting a new body and new lenses. And I am facing this issue every time I try to decide. I look at the GH4, and I look at the native lens selection and what you pay for them, and what they do compared to full-frame or APS-C lenses and what you pay for those, and the value seems off. I get much more for my money with the larger-format lenses. But I pay more for the body that handles those lenses, and the body may not be as good for video anyway. It is, after all, the combination of lenses-plus-body that produces the actual images.
  25. Like
    AndrewM reacted to KarimNassar in Must watch video on full frame vs crop cameras. "Full frame look" covered.   
    I do not see how it is possible for a full frame lens to provide the same amount of light to a crop sensor as it would to a full frame.
    Unless you are using a speedbooster.
     
    Now we are talking amount of light only, not sensor sensitivity.
     
    Saying a f4 full frame lens becomes an f2.8 with speedbooster on a crop sensor is in my opinion false.
     
    We all know for fact that speedboosters increase the amount of light on the sensor.
     
    But how?
     
    I say : you lose light on crop sensors to begin with and speedbooster makes up for the loss by focusing the lost light back on the crop sensor.
     
     f4 full frame = f4 on crop with speedbooter
     
    You say : there is no loss to begin with, and speedbooster increase the light on the sensor compared to full frame.
     
    f4 full frame = f2.8 on crop. I don't see how that works, please demonstrate via graphic how that works
     
    This is how I understand it, please do correct this if it is wrong:
     

     
     
     
     
     
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