digibud
Second Officer
Flight distance : 7820246 ft
United States
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This really misses the point all over the place. I'm not quite sure the presenter really understands polarizing filters and their use. That sounds like a bold statement but while he does point out the the issue of an image shot with a polarizer will show a dark area in the center if the shot is done with a wide angle lens 90deg to the sun, he then goes on to show an image of houses where he explains the sun is in back of him but the polarizer is allowing the viewer to see through the windows and makes for a deep rich color in the grass. Nonsense. I'm happy to be proven wrong but a polarizer...polarizes light...and that only happens when the light is coming from a reflected angle with the greatest polarization (from the sun, typically) happening at 90deg and ...none...at 0 or 180 degrees. I will admit that there may have been some light coming from clouds that were in turn reflecting the sun light so there may have been some light in that image particular image that could be polarized, but look at a car windshield with glare from the sun shining from your left with and then compare it to the windshield viewed without a polarizer. The polarizer will have a huge effect. Look at it with the sun in back of your or directly in front of you. No effect. Bottom line is a polarizer works on light reflections coming from an angle. Using a polarizer on video shot with a wide angle lens can be fine...if in general you leave the darn sky out of it. The video explained the problem but glossed over the issue shooting video with something like "take care in planning"....well...even if you plan to shoot in one direction and never move the camera lens from left to right, on a sunny day you still end up with a dark area with lighter sky on either side if you are using a wide lens like the M3 standard lens. If sky is involved, polarizers, for the most part, have no place on video shot with wide angle lenses although they can be useful in other ways. Still images and video without sky can work wonders but you really can't shoot wide angle video with sky and a polarizer without a dreadful dark/light sky issue. He implies that polarizers get rid of glare shooting through windows and "works on everything...grass...leaves on trees..." but the innocent purchaser will be shocked when they take a picture with the sun in back of them and find the polarizer does virtually nothing. The presenter also glossed over the use of ND filters saying you use them with video because you want to shoot at a shutter speed of 50 when shooting 25fps because that combination would let too much light in so you need an ND filter so you can "get that really nice slow smooth footage". I say he "glosses over ND filters" because their use isn't for "nice slow smooth footage..." it is so you can create motion blur, the kind we are used to seeing with cinematic film, as opposed to the sharp motion blur free frames you get shooting at 60fps with shutter speeds of 1/500 or some nonsense. Saying you want "nice smooth footage" implies you kind of -always- are looking for that but if you are in a drone shooting from 4oo feet at the ground or almost anywhere, shooting with ND filters will do virtually nothing for you. Shooting with a shutter speed double the fps is a common thing because motion in the foreground and quick moving foreground objects (think fight seens) will then create an appropriate motion blur - the kind we are used to seeing from movies done with film. Picture yourself filming a car from the side and your drone flying through the are, as you zoom by things between you and the car. The objects will all have a nice motion blur if you can shoot a shutter speed 2x your fps but that becomes meaningless if you are shooting the ground from 400 feet. The presenter makes both ND filters and polarizers to be much more useful on a day to day basis than they really are. Both are meant to be used for very specific situations in very specific ways and this video does a poor job of explaining their uses and limitations. All in all a very disappointing video from my perspective; probably a great one from the company's perspective. Correct me where I'm wrong. |
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