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Brian Luce

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Posts posted by Brian Luce

  1. For video I use manual focus on my NX1. Today I was experimenting with auto focus (in vidoe mode). It seem it only focuses fully automatically. Questions:

    1) is there a semi auto focus mode? Meaning depress shutter button half way, the camera will auto focus, and lock the focus and not hunt regardless if the camera pans or moves.

    2) If #1 is possible, can you do it while camera is recording? or only standbye?

  2. ​How would you know this and why would samsung agree to this ? magic lantern hacks features that are already there, features canon don't want to give or don't want to officially give because they can't guarantee it will work properly.

    On the other hand, samsung want to give it all, i see no reason to employ others when they can do it in house.

     

    ​I cannot say, but I know people associated closely with Samsung. I don't know anyone at ML, but I have credible sources inside Samsung from way back. As I said, nothing is concrete, but I can assure there is a dialog. It's not something either party wants to publicize just yet, and some have already been in hot water for talking too much. There is nothing more I can say on the issue. 

  3. ​FS700 is absolutely not a camera to use without rigging it up IMO. It can be very usable once you get a decent riser (+shoulder pad) and some good handles on it. Difference is that the FS7 already has that built in. I haven't used the FS7, but I do love shooting a kitted up FS700 with a 7Q right in front of my face.

    ​Yeah, I've used the fs700 with the movcam rig and all kinds of zacuto crap hanging on it with the Oddysey. It's nice but takes some time to assemble. and it  tends to be front heavy. Maybe the F7 is more convenient. 

  4. If only magic lantern ppl started to work on a nx1....they could even unlock the rumored 6.5k video...great for taking stills from it, or the 240fps at 1080p.

    ​Magic Lantern is absolutely in talks with Samsung on this. They don't have a game plan jus yet AFAIK, but I can say with 100% certainty that the two parties are talking about it. Will Samsung give ML the keys to the Palace? I don't know. But for sure, they are talking. 



  5. The FS7 is completely different to the FS700. The FS7 is a very serious tool, built to last for years. I'll miss the FS700 but times are changin'. ;)

    ​Nutshelling it, what are the big differences? The shouldermount must be one right? I don't like the ergos of the fs700.

     

  6. ​Fun. Yes. I had a mechanical Bolex and developed the B&W films myself. Wouldn't you agree you had to get much more parameters right intuitively (w/o proper preview, w/o proper exposure assistant, w/o sound) than with any of the digital cameras of today? I also had a Kiev 6x6, which had a light meter built into the (detachable) reflex viewer. I found out for myself that guessing the right aperture and shutter (relative to the stock's speed) by simply looking at the ground glass got me better results. If we have to fight some moire now, and if that's our major pita, there's no need to despair. 

    ​But at the same time, film is more forgiving. Get a light meter and you're good to go. The film cams I've used all had them built in -- but a handheld was good to have. But sure, instant replay in cam is tough to beat. 

  7. Fair enough. There are circumstances in which you'll see it (chain link fences back to back, because one is working as a a system sampling the frequency of the other), but when looking at one chain fence, or straight at fabric... or one part of a system... you're never going to see it.

    So while it's not completely alien to nature, it's still nice to reduce it. No matter how much you stare at that brick wall it won't moire without something else in front of it.

    ​Yep, I still hate it. I have a continuing, haunting fantasy of selling everything digital and getting a sexy Arri S16mm. 

  8. It's not an electronic phenomenon (what does that even mean in this case?), it's a mathematical one. Read up on the Nyquist-Shannon sampling theorem. When one system samples another system there's potential for aliasing at frequencies above half the resolution of the system that's doing the sampling. This could mean music recorded at 44.1khz might cause aliasing in frequencies above 22.05khz (which is just above the cut off for human hearing). It means any sensor that's resolving more than 25% (50% in either dimension) of its megapixel count is also aliasing except when something optically reduces the resolution of the information going into the system below that threshold. Usually no one notices just a little, though, and most dSLRs alias when shooting stills under the worst circumstances... but just a little... and resolve roughly 70% resolution in either dimension at best.

    That said,​ when have you seen aliasing induced by your eyes? I would argue no one ever has. When have you seen aliasing with your eyes? Only when there is a system offering a signal and another filtering it. You see it when you see it in images recorded with sensor that is prone to aliasing because it is sampling information beyond the Shannon-Nyqvist limit. You see it when you see one screen door through another at the right frequency (one screen door is the signal... the other is the system filtering it...). But the system that induces aliasing is never your eyes, because your eyes as sensors are so high-detail that it's effectively irrelevant and beyond diffraction-limited and, more importantly, the rod-and-cone pattern is too random to have any statistically significant chance of aligning with another system. (Whereas sensors are grids... and there are plenty of grids and lines out there.)

    So no, the eyes do not cause aliasing at any frequency, no matter how high. They can see aliasing when it occurs as a result of another system sampling something about the Shannon-Nyqvist limit, however. So... stacks of screen doors, fences, etc. can cause a moire pattern.

    But what you're suggesting (that the eyes can induce aliasing) is mathematically and objectively wrong, but maybe psychologically right, sure, in that it's not a foreign phenomenon experientially. We've seen aliasing before in real life when screen doors or wire meshes overlap and seen it in plenty of pictures. So when we see it on camera, it's not too foregone. But when we perceive it in life it's always a product of two systems interacting, and neither of those systems is ever your eye (whereas it could be a sensor.. or meshes... or whatever). You will never see moire induced by your eyes alone. Always one system interfering with another before getting to your eye. Whereas a dSLR sensor (CCD or CMOS) can induce aliasing whenever it captures detail above the Shannon-Nyquist limit; thankfully most OLPF knock out the majority of detail that causes really bad aliasing... except that line skipping decreases the Shannon-Nyqvist limit by a factor of three (if you're skipping every other line) and the OLPF obviously isn't blurring things that much!

    Same goes for film, actually. Random dot pattern doesn't induce aliasing. Can't. Won't.

    The same idea that explains why line skipping causes aliasing explain why the Alexa has bad aliasing with red fabrics (the C300 even worse!). The OLPF is designed to knock down resolution for green/white light, but the pixel count for red pixels is pretty small on any Bayer sensor. So when your signal is mostly red, it's getting through the OLPF with more than 50% of the frequency of the red pixel array. Thus... aliasing.

    Can't imagine red fabrics through the 7D. :P;)

    I've never seen aliasing with my naked eye. And I don't know about inducing moire with the naked eye in the sense you mean, the take way should be, for video, that moire is something you can perceive with your naked eye. Moire is part of real life, not just digital life. That's the key.  You don't even have to be an android to see it   -- though I'm told it helps.. 

  9.  

    5) The human eye does not see any more moire than you put in front of it. If you put an image of something that has moire in front of it, it will see it, same as with film, which also doesn't otherwise alias. 

     

    That's thing though,  like a lot of people I used to think Moire was a purely electronic phenomena. But the naked eye CAN see some moire and it very much looks to be some video related artifact, but obviously it isn't otherwise why is the naked eye visualizing it? Once you realize that moire is part of real life, it makes it easier to accept something that shows up on your NLE the next day. I worry much less, generally, than most of you guys here about resolution and even DR, my biggest concern with a motion picture image is the presence of artifacts that look electronic and thus break the 4th wall. Moire perhaps shouldn't be the cringe inducing apparition that it's made out to be. 

    so in other words, I'm suggesting a purely psychological remedy here. 

  10. Not to go off topic, but the A7s is a bit awkward in terms of hitting REC. Others have the same complaint. I shoot 90% video, for a true hybrid shooter maybe it's okay, but if you do mostly vid, I can think of other cams with layouts I like better.

  11. If at all possible. control wardrobe. I find moire more distracting on people than I do on inanimate objects. Meshy fine patterns should be avoided. Solid earthtones!

    Try and get a good monitor so you can spot the moire and maybe take some of the steps Axel suggests. Trying to fix it at home in your desktop is difficult, fix it before you record to your SD card. 

     

  12. 1) Avoid shooting subjects that produce it

    2) Get a  Super 16mm Arriflex

    3) Get a CCD Camera

    4) Try some mist/softening filters

    5) appreciate that the naked human eye sees Moire and learn to accept it a "Realistic" filmmaking?

     

  13. To me, even the image an iPhone produces is amazing compared to what things were like 10 years ago. 5 years ago I would've said the limiting factor is no longer your camera. It's you. That statement feels truer than ever with the gear we have now. You can get a used GH2 for $300. If you cannot make something interesting with that, an Arri Alexa won't save you. 

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