If you can't tell the difference between arri and iphone footage then I doubt your video experience is in the market bm, arri and red and higher up canon cine are aimed at. If you've ever edited anything or been involved with lighting complex scenes you'd know a phone can't do what cine cams can. Sure they may look the same for certain situation and lighting when operated by the youtube content creator types but imho they are barely scratching the surface of the capabilities and would be just as well served with a dslr.
Fwiw I am not a serious video guy, although have actual independent cine folks in my family on fathers side (although he is still guy himself but got out at the end of film). None of the cine members in the pro world use dslr's (in my family I mean) never mind phones for a reason. Good luck getting your iphone to output something that has enough editing headroom when they are all compressed 422 at best I imagine. Bet some of my relatives can tell sitting at their grading desk. These cameras are not aimed at the likes of you and I and those that NEED them know why and it isn't meaningful OOC files at same settings look the sameto us posted on facebook compressed to hell. Not to mention phones don't have any choices on lenses, high DR demands of some scenes, flexibility of settings, accessories and compatibility with them and how they fit into lineup with other cameras used on set and so on.
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You take 4K footage shot on any major Smartphone at 4:2:2 (preferably 4:4:4 if you can use that recording setting on your camera software), use Lanczos-3 or Lanczos-5 resizing (i.e. a 3x3 or 5x5 resampling filter) to get it down to 1920x1080p 4:4:4 uncompressed for editing, increase brightness by 5% to 10%, reduce highlights by 15%, boost shadows by 10% to 15%, increase contrast by 5% to 10%, increase saturation to personal taste AND finally add EITHER a slight Unsharp Mask for edge-enhancement (i.e. sharpening) OR an Antialias Filter...AND BOOM you get near Arri Alexa quality! I do this nearly every day!
I am NOT some average Vlogger but rather a guy with 30 YEARS of video/cinema experience on everything from 1987 era Betacam SP to Arri 2.7k to 4k Canon C700 to 8K Red cameras to Multi-camera 360 degree surround view 4k/8k setups. We do use a LOT of lighting with 5k, 10k and 20k HID cinema lighting setups on our industrial, scientific and commercial photography/videography sets. AND YES we HAVE used Smartphones and GoPros on these complex setups AND MATCHED them to Arri-shot or Canon-shot footage! When you use LOTS of lighting, shooting with smartphones works GREAT!
We have had 30 second and 60 second Car Commercials RUN on major North American, European and Asian Network TV shot ENTIRELY on iPhones! And for SOME REASON, more and more of my requests ARE for using/shooting on low-cost cameras such as smartphones from the major electronics companies! I no longer have a problem with those requests since even our scientific imaging department which I normally work for is getting in on using ARRAYS of smartphones as their imagers!
I have seen our aerospace parent company shoot it's videos in the toughest of Ground and Space conditions on small camera systems so Computational Photography has come a LOOOOONG WAY!
On a technical note, if you shoot 8-or-10-bit 4:4:4 on an iPhone and shrink the 4K footage DOWN to uncompressed 4:4:4 1080p resolution it actually DOES look utterly fantastic! It's just math and pixel averaging which makes it look good! It's in LOW-LIGHT situations where I can tell from basic noise floor measurement which camera is which but since MOST of my imagery uses LOTS of natural and artificial lighting, we can get away with shooting on Smartphones. (this is done BY REQUEST OF THE CUSTOMER as normally I shoot on Canon C700 Global Shutter or Full frame or a Red Monstro and sometimes the odd rented Alexa-65!)
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