DoctorDrone
lvl.1
Flight distance : 6230994 ft
United States
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Drone Man... great question. I'm no pro either, but I have a little bit of understanding and can offer my 2-cents. It's complicated to answer because their are many variables to consider when deciding what video size/quality/resolution and fps (frames per second) to shoot at. To start, we will refer to size/quality/resolution as "size". Size and fps are 2 separate issues. The P4 offers the following video modes or settings according to DJI Phantom 4 specs:
UHD: 4096×2160 (4K) 24 / 25p
3840×2160 (4K) 24 / 25 / 30p
2704×1520 (2.7K) 24 / 25 / 30p
FHD: 1920×1080 24 / 25 / 30 / 48 / 50 / 60 / 120p
HD: 1280×720 24 / 25 / 30 / 48 / 50 / 60p
The first part of each mode is the size of the image (Width x Height). A full HD image is 1920 x 1080 for example. In my opinion, the "labeling" DJI uses in their specs are a bit inaccurate, as UHD and 4K are two separate formats, and are often referred to interchangeably. In the DJI specs, I believe they incorrectly call 4096x2160 "UHD (4K)"; and 3840x2160 "4K". The accurate labeling would be 4096x2160= DCI 4K; and 3840x2160=UHD (Ultra HD). The differences are minor, and not noticeable to most people. I will give a short synopsis of each format below:
--HD (1280x720) or 720p (921,600 pixels) has a ratio of 16:9 (the ratio of most computer/tv screens these days). It's a slightly wider format than the older more square looking monitors/tvs with a 4:3 ratio. When you view an image/video shot in a 16:9 ratio on a monitor/screen that is 4:3 ratio, part of the image from the left and right sides are cut off because of the cropping that takes place to fill the screen from top to bottom. If you see black bars on top and bottom, then likely the image isn't cropped, and you are seeing the full image. IMHO 720p has no valuable use anymore, as the other formats are so much sharper and as easy to handle in post production and rendering etc. The only time I can think of that it might be useful is if you want a really high frame rate (fps) like 120-240fps in order to create slow motion in post. With a really high frame rate like 240fps, when you play it back at 24fps, you get really smooth slow-motion effects. But at 720p, the image won't be as sharp as we have become accustomed in the past 5 years or so.
--FHD (Full HD) (1920x1080) or 1080p (2,073,600 pixels)also has a 16:9 ratio. This is maybe the best format to use when your end result is to share videos with friends and family on your computer. It can be rendered quickly with most computers, and handles easily in post production editing with iMovie, Final Cut, Premiere, etc.. It can be shot in up to 120fps, which gives a really smooth look in slow-motion. This format is fairly sharp on most TV's also. HOWEVER, with the newer UHD and "4K" TV's, we won't settle for 1080p much longer if we are using it on anything but phones/computers.
--2.7K (2704x1520) (3,110,400 pixels) has a 16:9 ratio too, and is a bit sharper than 1080p. Many cameras don't shoot this format, as it was kinda skipped over as technology went from 1080p to UHD and 4K very quickly. I don't think you can shoot at a higher frame rate than 30fps anyway, which you can get from UHD. So lets move on.
--UHD (Ultra HD) (3840x2160) (8,294,400 pixels) also a 16:9 ratio is frickin awesome! This is very sharp and clear and looks fantastic on large screen TV's that have UHD/4K capabilities. If you need to zoom in on part of the video image in post, you can, and still will have a pretty sharp image equal to at least 1080p. I would shoot most stuff in UHD. This can be downsized in post for smaller file size if needed for Youtube/Vimeo sharing etc. YouTube will allow up to UHD/4K uploads, but most people can only view in 1080p or less. Vimeo (at least at one time) would charge for premium service for anything uploaded higher than 720p. Not sure if that's the case anymore. Also, although you may be able to upload UHD/4K to online video sharing sites, their disclaimers state that it will only be for future use/capabilities; so even if uploaded in UHD/4k, they only allow viewing up to 1440p (last I checked).
--DCI 4K (4096x2160) (9,437,184 pixels) NOT 16:9; the ratio is actually 256:135 or commonly referred to as 190:1 for short. Notice the height is still 2160 just like UHD. This means to fully realize the value of this setting, you would need to view on one of those NEW monitor formats out there that are super wide and have a 21:9 ratio screen. So a comparison would be this: remember how we lost part of the image (if it were cropped to fill from top to bottom) when we viewed HD images on a 4:3 screen/tv? This will now happen on a 16:9 screen when trying to view true DCI 4K 4096x2160. Either you will have black bars on the top and bottom so you can see the full image left to right, or if it is cropped to fill the 16:9 screen from top to bottom, then the left and right portion of the image will be cut off. That being said, you will likely have to zoom in a bit in post when editing your videos shot in 4096x2160, which in essence gives you a UHD image that is 3840x2160 anyway. So why not just shoot in UHD for now!
Again, fps is a different issue. There are other effects besides great, smooth looking slo-mo you get from high frame rates such as 120 or 240fps. If you are shooting something that is high speed, such as race cars, sporting events, water drops, etc., where you want to see detail in every frame, then higher frame rates might be a wise choice. However, under normal viewing, a slower frame rate (30fps or less) is more pleasant to the eye. We have become accustom to the cinematic look which is 24 fps (23.97 exactly). 25fps is mostly a standard used in Europe. 24fps makes video images flow more smooth, where higher frame rates seem to have more flicker or seem more jumpier for the lack of better terms. Sometimes that's the effect you may want for the purpose you are going for. Then there is the issue of what shutter speed to shoot at based on the frames per second you are shooting... that's a whole other subject, but closely related. I won't get into those details here, as I am running out of ink (haha); but as a general rule of thumb, if you are shooting in manual mode, you should set your shutter speed at roughly double your fps setting, So at 24 fps, your shutter speed should be at least 50 etc. This helps reduce some "jello effect" and other artifacts that result in mis-matching the shutter speed with fps.
Sorry this was so long... hope it helps. |
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