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Everything posted by kye
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You're probably right, and it stabilises movement between frames but it doesn't stabilise movement during the frame, so if you're in low light and bump the camera the stabilised shot you get out of it looks like you had a very steady hand but at the moment of the bump everything in the frame will turn to a mush of motion-blur like all of a sudden the universe had a tiny little seizure. It works for action cameras filming at very short shutter speeds but doesn't really work for anything other than wide-angles in sunlight. As soon as the sun sets or you decide you want to use that 50mm or 80mm lens (with its tiny aperture, tiny sensor, and poor ISO performance all pushing to slow the shutter speed) then it's universe-seizures the whole way.
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I'd seen the website (and even added a lens myself) but hadn't seen that a few lenses had service manuals - pity mine doesn't! LOL, I'm not doing this for lack of entertainment I've watched quite a few lens teardowns and unfortunately they're all really different when it comes to the details. Even to the fact that the initial move to take apart the 200mm F4 S-M-C Takumar doesn't work on the 150mm F4 S-M-C Takumar despite the fact they look identical from the outside!
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Just dismantled, cleaned, and re-assembled four lenses. Three of them still work! The normal way to disassemble a lens is to take some of the elements out of the front, and some out of the back, and there might be a third group in the middle somewhere a bit deeper. So, I took the back off the Minolta 135/2.8 and then unscrewed the rear lens group, which came free from its thread but there was no way to grip it and pull it up, so I then did what any normal person would do, I put a cloth over the top and turned it upside-down. The rear lens group came out, but unfortunately so did 6 curved pins and 4 of the smallest ball-bearings I've ever seen (maybe 1mm diameter?). The ball-bearings didn't concern me (look - I de-clicked the aperture without even trying!) but the pins were a bit worrying. I was taking photos as I disassembled but nothing showed these pins, and long story short, they play some crucial role in the aperture. So I now have a Minolta 135mm fixed at f2.8. Focus still works fine and image looks great but no stopping down unfortunately. To be fair it's pretty sharp wide open and it was a pretty knackered sample of that lens anyway - full of dirt, fungus spots, and the focus has no friction to it, it just moves like it's not connected and then stops. So if I decide that that is the lens for me (I had already decided it was a keeper unfortunately) then I can use it at 2.8 or buy another one and not take that one apart. TBH I'm a bit annoyed that the aperture mechanism wasn't a little better designed. That was the fourth lens I took apart and the others were just fine. Maybe it was broken in some way but who knows. Anyway, I learned a bunch of things, including that fungus spots are easily cleanable with a weak mixture of dish-soap and water. I also learned that with distilled water and an air blower you can clean a lens until it is invisible, even if you shine a LED torch right through it.
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Who wants to see a magic trick? Watch as the lens gets fogged up and then when I take it apart the fog is instantly gone! It did it about 5 times in a row, and that one wasn't even the first attempt I had at filming it (it's hard to hold the camera and do something at the same time). I have a feeling that it's to do with the pressure as the lens element is a really tight fit, so when it gets slotted in there the humidity condenses. Anyway, I heated it up by putting it on a warm appliance for a few minutes and took it apart and then put it back together and it's fine now, but wow. Fun times! Edit: still happening. It seems to be only when I pick it up. So I guess I'll just reassemble the lens without touching anything then ??????
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I would romanticise LA, I've hear that the movie permit police are much more effective than the actual police.. I heard a story about a guy shooting a music video inside a warehouse they had rented got hassled because the people wanted to see their filming permit - inside and on private property! If you shoot it in LA it might be more work to get all the paperwork organised than it would to stay home and build yourself a sewer! Go on google earth and near where you live and have a look for any buildings that look enormous and then try and work out what they are and if you can get there. You probably have an idea of how big you need it to be, so you could start with that. Also, you could use the same background multiple times if you're willing to dress it up a little. Eg, the character walks the length of the wall, then next time they do the whole thing again but this time it might have some things hanging on it or broken furniture or whatever, then again but with different stuff. Walls are pretty repetitive (think about bricks or posts - they're basically a repeating pattern) so if you can disguise any notable bits then you could have an infinitely long wall, and bonus feature is that you wouldn't need to move your lights all the time
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Sewer is an obvious one, but also anything that doesn't have windows, and probably also doesn't have graffiti (as that's a give-away that people go there). Disused railway tunnels, abandoned buildings, even just a really long wall perhaps? If you film at night then it won't be obvious it doesn't have a roof. Lighting something that doesn't have a roof might be tough, especially if you want a single long follow-shot where you can't cheat by using the same few lights again and again. If you can cheat then film it with a couple of angles (wide, mid, close) then move the back light to the front and shoot them walking the next section, with a bit of overlap, then cut it together in the edit? Obviously be careful with safety and trespassing and all that, but IIRC you're out in the country so there might even be a long building or wall that you can film against that wouldn't even be on private property, or maybe no-one cares. If you want it to be wet and underground then you could spray the background with water just before the actor is in frame so things are dripping and add in wet echo-ey noises in post and drop the blacks a bit to hide anything that gives the game away.
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@leslie nice to see progress - we all make mistakes - the smarter we are the more bone-headed the mistakes seem! I've also played the "modify it, clean it, test it, repeat" game and there are definitely less frustrating ways to spend time that's for sure! You've already modified the middle ring, so if gluing it is an option then it might be a good one? I'm not exactly following the details on how it all fits together, so maybe it's not a good idea. But if you wanted to test it, maybe try hot-glue? It's messy to work with, but cleans up very easily, should hold nicely if you get enough of it on there, and if you ever want to take it off then just heat up the part until the glue melts. Assuming you can screw the adapter in, even just a few dabs of it from the outside (like tack-welds) might help?
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This is a tricky subject, but you have nailed it with your comment "seems to be a lot of opinions". Just like everything else out there, if something is engineering or science, there will be a lot of opinions, and almost be definition they will all be WRONG. People who have OPINIONS about engineering or science are people that don't understand FACTS. I'm all for having opinions, we can talk about who likes what colour science, lighting design preferences, lens aesthetics or if someone is a good actor, but anyone who has an opinion about how many pixels are in the UHD specification is just stupid. This is the same thing. There is a huge level of knowledge about how to get accuracy beyond a certain bit-depth when talking about audio, as properly recorded and processed 16-bit audio can have better signal-to-noise ratios than is mathematically possible because of a technique called dithering which works by adding a very specific type of noise to the signal. https://en.wikipedia.org/wiki/Dither Fortunately, ISO noise on high-quality 4K cameras is a relatively good version of that noise, so we can get a lot of the benefits. Downscaling from 4K to 1080 also involves oversampling which when combined with dither can extract the extra bit depth and eliminate the noise that was added. https://en.wikipedia.org/wiki/Oversampling There is an audio format called SACD which uses a type of digital signal called DSD, which is a 1-bit (yes, the bit depth is one bit!) at 2.8224 MHz, and because of its clever use of noise and processing, can have signal-to-noise rations of up to 120dB, which would require a 20-bit signal from a traditional codec, but because it is oversampling (in a big way) this effect can be achieved. Getting 20-bit from 1-bit is only possible because DSD has about 64x the sampling rate compared to 44kHz audio. https://en.wikipedia.org/wiki/Super_Audio_CD If DSD gets 19 extra bits from a 64x oversampling, then it shouldn't be impossible to do a similar thing with video and get an extra bits from resolution oversampling. However, and this is a key part of the picture, you will only get perfect 10-bit 4:4:4 1080p from 8-bit 4K footage if that 4K footage is RAW and the noise is perfect. Any variation in de-bayering, compression or any other processing that is applied in between that data coming off the sensor and the downscale will have a damaging effect on the final result, and this is where reality differs from theory, and it the overall quality will be different depending on the camera, codec, bitrate, subject matter, and probably other things. If none of that made sense, then here's a TLDR approximation - adding noise to 8-bit helps with banding similarly to why adding noise to your footage helps with YT colour banding. The mechanism is very different, but the effect is broadly similar. Anyway, let's put this to bed and go back to talking about cameras ???
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Nice video! I make home videos for my family and that's a great one - I'm sure they were really happy. One of the reasons I like doing projects like these is that that footage will have a life of maybe 100 years or more, and it will become more valuable to the clients over time instead of less valuable like a 2-year-old TV show or movie or doc that no-one remembers. I'd also imagine that if you're adapting FF lenses they'd easily cover the whole sensor.. even with a 0.7X adapter? Here's a pic to get you fired up.. SLR Magic 8mm on GH5: and if that tickles you then you'll absolutely love this one.. Lomo 40mm on GH5 via an adapter and mounted in a hole cut in the body cap (it was a fixed lens with proprietary mounting thread so no adapters available):
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The GH5 has a mode called Open Gate where it shoots with the whole sensor - 5K 4:3 video. This mode has less sharpening than the 4K modes with the sharpening turned all the way down. Also, you can soften things up in post quite easily too. Your vintage lenses will also do that in-camera if you're using them for those shots. I don't know what editing software you are using, but if you have the time and energy to do it, Resolve has a free version that you can use to basically make the footage look however you want it to look. There are also LUTs that make the GH5 look like an ARRI Alexa, including the sharpness, so the image coming out of it is very flexible if you want it to be. 4K can be downsampled to create extra bit depth and colour information, however it depends on how the codec performs and how much noise there is in the signal (less is worse). The explanation is very technical, but basically it works because for every 1080 10-bit pixel you get after the conversion, you've averaged 4x 8-bit pixels, and so the average can be between the 8-bit limitation, and those 4 pixels contain all three colours before debayering. In practice it will be somewhere between 10-bit 4:4:4 and 8-bit 4:2:0 depending on exactly how that camera operates, but the benefit is real. If the OP is willing to wait for the computer to render proxies and take longer to render out the final project then basically any computer can edit any resolution. We forget that people used to make broadcast TV in SD, which is 27x less pixels than 4K. Resolution pretty much doesn't matter when you're editing (it matters when you're grading or doing other things) so that means you can render proxies and edit them nicely on a computer that is less than 4% of the performance required for 4K editing. I render proxies at 720p and edit them on my laptop on the train. My computer is perfectly capable of playing 4K files but I don't need the extra resolution and saving space on the internal SSD that I'm editing from are advantages too.
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Absolutely. I'd also suggest trying before you buy. One of the things that I thought the GH5 would be absolutely great at would be focus peaking, but it didn't stack up to what I had in my head. To be fair I'm not sure if anything does, but there are situations I found it wasn't that great (ie, terrible) but there are ways around it with punching in to focus, and it wouldn't have changed my decision to buy it, but it was still a disappointment. Sadly, as good as the GH5 is (and I absolutely love mine) no camera is perfect and every feature has its limits on every camera.
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@kaylee You should also have asked if anyone has heard of it because of the latest news. I hadn't heard of that either, in fact, the only reason I am aware of it now is because you asked about it... Maybe it's a big news story and maybe not, I don't know, but what happens in the US is far less important when you don't live there
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Daylight WB and shooting straight into the late afternoon sun. If it works for Philip Bloom......
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Flaring is interesting, I don't really know how that works - if it's different at different apertures or focal distances. The frame is getting kind of crowded at this point! The one thing that this test won't be so good for is the imperfections because most of these lenses are FF and I'm using a MFT sensor, so the lens could have dancing bears in the corners and I'd never know it. This is where CA and the other issues tend to exist, so unfortunately this is a "lens on MFT" test. Having said that, I do want some things in focus near the edges / corners so we can at least see how bad things are on MFT. There should be lots of things in the slightly out-of-focus areas so I think that's covered. Smooth like butter!! It really is incredible, and my one is virtually brand new. The other Takumar lenses are all just as good, if a little firmer. It's a pity they don't look as good or have the focus ring going in the right direction ???
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I don't use AF on the GH5 so can't comment. Camera reviewers make a big deal of these things, but what they don't tell you is that they're often using it for recording the camera reviews they make. I would imagine it's quite a personal thing, depending on the circumstances that you put the camera into. I think it's kind of gotten blown out of proportion really, it seems like the GH5 can't ever focus and the other cameras never miss focus, but that's just not true. Even if it was 90% vs 95%, that's still 90%. I don't think the XT-3 was out when I bought my GH5, maybe I'm wrong. I guess in the same way that people think of the AF on the GH5 as "risking it", I thought of other cameras IBIS as "risking it" when the GH5 was the IBIS king for a long time. I shoot almost exclusively hand-held so the IBIS is a huge deal for me. I'm not 100% sure that it is still the IBIS king now, but the combination ofnnearly the best IBIS, 10-bit internal, huge range of lenses available, rock solid industry standard performer was really the balance of things for me. People say the XT-3 is great, and they're probably right
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Ok, that makes sense now, I think. But you've convinced me to shoot some video Maybe I can put up the stills and see which ones people want to see video for. That way I'm not carting around a whole suitcase full of lenses!
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I struggled for ages with criteria that sound like they might be similar to yours. In the end it came down to the Sony A7III, which has good AF and fast but expensive FF lenses, or the GH5 and 10-bit files with the reliability, lack of overheating issues etc, and pro features it offers but limited AF. I ended up deciding that going to manual focus worked for me and my style of film-making, and because the IBIS is so great you can adapt old lenses and still get great hand-held footage, so I now have the GH5 and a cheap ebay vintage lens collection that is so large that I hide it from my wife.
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LOL, I was trying to imply motion cadence doesn't exist, more that no-one seems to know where it is With people moving in the background etc, is that a function of how the out of focus areas are rendered? Like, bokeh balls with hard edges look great for city lights but are really distracting for everything else? Or is it something different?
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The $7 Petri 135mm f3.5 was the first to have cleaning attempted, and holy wow did it need it. It was absolutely filthy. There's a lot of discussion online about how Petri lenses are high quality Japanese lenses, but are "uncleanable" because the manufacturer glued the screws in, and even things like soaking them in acetone for days doesn't loosen them. Someone broke a screwdriver trying to get one apart. Luckily I had no problems with the screws on this one.. Unfortunately, I had two kind of trouble, the first was that I couldn't get the front element out. I tried the old elastic bands and a lens rear cap, I tried PVC pipe and blu-tak (bad idea, it just gets pushed into the grooves), lens caps and tape, nothing would make it move. This is a pity because there is fungus between the front and next element. I was able to clean the back of the second element, which was filthy - it looked like someone had wiped the kitchen and bathroom benches and then tried to wipe this out. Soapy water and rinse cycle of distilled water got it nice and clean. Then the last element came out ok, but unfortunately it was actually two elements glued together as one lens, and naturally the filth was in-between them, so game over at my current skill level. You can see it a bit in the pic above. However, I was able to clean both sides of that, which was also needed. Now it's back together again and still works! Bonus!! Did I mention it was dirty?
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I think vaguely, yes, but I know nothing about it, including where I might have seen it or where to go to watch it, or even if I should.
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Damn, I was hoping you wouldn't have any good points, but... I'm not sure that movement is impacted by lenses, they all let light through in a constant stream at, well, the speed of light, so I don't think the mythical motion cadence comes from the lens. In terms of how these things translate to video though, I may have to take a few of the lenses to a nice place and film some stuff so we can see. To me, if you can see lens X recording video and go wow, that's good at Y or not good at Z, then you can use the stills to kind of work out what the other lenses would be like. I definitely don't want to record video for every lens at every aperture setting, that's for sure!!
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Nah, it's the tiny spider drones and tiny insect drones that are the worrisome ones, because it doesn't matter how many locks you have on the door, they just come in through the vents and crawl on you when you're sleeping... ???
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Actually, this halation effect also comes from vintage lenses too. I just took this shot of a lens I paid basically nothing for on ebay and it's got the same fringing you show above: If you zoom in around the highlights you'll find that some stems on the plant are very red. (This lens is well regarded and made in Japan, but are available very cheaply because they are almost impossible to take apart and clean)
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So, I discovered that the Petri 135/3.5 was marked as delivered a couple of weeks ago, and "left in safe place near front door" and I searched for it but couldn't find it. I assumed it was lost or the postman stole it or whatever. It was $7. I was more concerned with the fact I paid almost double that in shipping! Anyway, a lady knocks on the door - she lives some way down the street and found it hidden on her front verandah.. the mighty Petri lives!! So, after cleaning it up (it was absolutely filthy, I think they stored it in a barn, or in the glove box during their desert crossings) and moving the focus control for the first time in about 1000 years back and forth until it stopped making grinding sounds, I took a few test shots. You know how they say that "there's no such thing as a bad 135mm lens", well, I don't know if that's true, but if there is you should pay a lot less than $7 for one, because this one is lovely! A little soft wide-open, sharp as hell stopped down a bit, lovely hex shaped bokeh, and it even has a little retractable sun-hood, and came with a soft pouch (that hasn't aged well). The mighty Petri 135/3.5 (image taken with Konica Hexanon 40/1.8): Sample shots wide open - unedited in any way: It's still filthy, and I think there's fungus in it too, but seriously... Oh, and these are on the GH5 with a straight adapter, so it's a 270mm lens on the 2x MFT crop.
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screw the hoverboard.. we've gone past the time that Blade Runner took place. I want robotic pets!!