Video Frame To Print Question
Bryce Wilson
Registered Users Posts: 1,586 Major grins
Forgive me if this is a stupid question, but I have absolutely NO experience with video. I have a few ideas bouncing around in my head and need to start somewhere.
When shooting video on say a D-800 or GH4, is it possible to make prints from one of the video frames?
If so, what type of video rate would be needed to get a quality 16x20.
When shooting video on say a D-800 or GH4, is it possible to make prints from one of the video frames?
If so, what type of video rate would be needed to get a quality 16x20.
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The quality of a single video frame grab is generally not sufficient for more than a very small print size (depending on subject/scene content). You don't mention your frame rate, capture resolution and whether progressive/interleaved, but even 1080p shot in the best possible circumstances is only around 2 megapixels.
Cropping to a common print size reduces pixel count even more. Even if you use the entire vertical count of 1080 pixels that leaves a width of 1350 for an aspect ratio of 5:4 (the same aspect ratio as a 20" x 16" print). This is less than 1.5 megapixels available for making a print.
If shot in low light the video shutter speed may not be sufficient to eliminate blur. In fact, video normally has some blur to make the video stream look smoother.
Some tips to get the best possible frame grabs:
Select a shutter speed of at least 1/125th.
Record in 1080p (progressive), at very least.
I recommend just getting some video editing software that has a frame grab capability so that you can see the resulting quality for yourself. Do some testing and I think that you'll see why making prints from a video stream generally results in poor quality and low resolution.
Moderator of the Cameras and Accessories forums
Question for you. If you were planning to combine video and still photography in a project, with one camera, is there a big benefit to going mirrorless? Or, would a Nikon product like the 7100 do the trick? (Got bunches of Nikon glass)
For long-format video, like wedding coverage, I still prefer a conventional digital camcorder with built-in zoom lens. (I use a separate dSLR for still image acquisition.)
For an "indie" film/video, or a true Hollywood style production, a video capable dSLR can work nicely, but good sounding audio can be a problem unless you plan on spending a sizable amount on appropriate audio gear too.
Most dSLRs are "mirror up" during video acquisition, with the exception of the Sony Alpha series which have a semi-silvered mirror. I believe that the Nikon D7100 is in the category of "mirror up" during video acquisition, so you're basically mirrorless during video acquisition and you use the rear LCD for framing.
For any sort of action, still photography, I think that passive phase-detect autofocus still holds a performance edge and benefit over a true mirrorless design, although mirrorless is improving.
Moderator of the Cameras and Accessories forums
If your still image quality demands aren't too great, you might also consider something like the Sony FDR-AX100 4K Ultra HD Camcorder, which can simultaneously capture both 4k video (maximum) and 2.1 Megapixel still images, or 20 Megapixel still images alone.
With a 29mm to 348mm (equivalent), f2.8 - f4.5 zoom lens, if you have (or if you supply) good light, there is enough capability to cover a number of applications. (I don't think that it has a hot-shoe or flash capability, if that matters. It does have a "Multi Interface Shoe", whatever that is.)
Moderator of the Cameras and Accessories forums
If you want to print nice 16x20s from video, buy a Red Scarlet or Epic (or Dragon variant). As for getting into 4K, the GH4 and BlackMagic Production cameras are both suitable, and the BM is slightly cheaper. THough it has no real stills capability and the video is problematic for some right now.
The GH4 and new Sony A7s is also a viable option and I would probably prefer that to a Panasonic for professional reasons.
4K won't getr you a clean 16x20, but it will get you a nice magazine cover. If it's 4K RAW you can upscale nicely to that 16x20 size.
perroneford@ptfphoto.com
How about another stupid question?
Does lens focal length work the same with video as it does with still images?
Example, when doing head, bust and even half length shots of people, I favor somewhere between 105mm and 135mm. Does the "distortion/compression" factor work the same with video as it does with stills?
The field of view is exactly the same in stills and in video. The sensor size difference between different CAMERAS will affect field of view, but on the SAME camera, nothing changes video to stills.
The GH4 sensor is quite a bit smaller than your D800 and that will most certainly change your field of view.
perroneford@ptfphoto.com
Thanks a lot! I expected as much but wasn't certain.
The ability to grab quality stills from a video frame at 4K is most intriguing. Wondering how much data space shooting at 4K uses per minute. I suspect that using an external hard drive while shooting would be required if shooting for any length of time.
Like everything else, it all comes down to compression. There is nothing particularly special about 4K in terms of recording it. It's all just 1's and 0's to the computer or recording device. The compression rate is what really matters. For VERY good quality, you could expect something in the range of 1TB per hour. But some 4K cameras are writing their data to SD cards! So it's a rate of 1/10th what I just mentioned.
For my own uses, I have a 2.5k camera. When shooting RAW it's about 480GB per hour. It writes internally to SSD drives. It can also write internally to ProResHQ of DNxHD 220. And that uses about 1/4 the space of RAW.
perroneford@ptfphoto.com
I'll report back with findings.
The Panasonic GH4 has a rated crop factor of 2x, meaning that a 50mm lens has a similar Field-of-View/Angle-of-View (FOV/AOV) to a 100mm lens on a FF 135-format body. Since the Panasonic GH4 has a different aspect ratio, compared to 135 format bodies, the effect is not directly the same, but partially dependent upon end use and output cropping.
I believe that the 4k video mode uses a crop from the sensor to provide an effective crop factor of 2.2x, or a little tighter crop than the full GH4 sensor view. The video output is also a different aspect ratio from the default still capture, meaning that the overall crop effect will be somewhat different too.
In the end, I believe that you will find focal lengths around 25mm to be approximately "standard/normal" FOV/AOF for the Panasonic GH4 in either still or video capture mode, with 18mm and wider starting the "wide angle" perspective, and 40mm and longer starting the "telephoto" perspective.
A 50mm lens (on a Panasonic GH4), or a little longer, would make a very nice portrait lens for head-and-shoulders and head shots, very much IMO.
Moderator of the Cameras and Accessories forums
Sounds like you have been looking into the Hybrid concept by Will Croc'oshit.
I looked into this a few weeks back and put up a thread here and on another site about it. Seemed my suspicuons were confirmed that this is not near the "Big new/ upcoming thing he makes out at all. Not even near it. Frankly, I and others feel he's more into pushing product and servcices of his own and the companies who pay him to spruik and talk up their products.
From the reviews I read, Mirroless cameras are not near what he makes them out to be and about the only advantage they have is size if you like smaller cams. That being the case, technicaly my G1X canon P&S is mirrorless and it shoots full 1080 Vid real nice. I can press one buttong for stills and hit the other button without touching anything else for Vid.
Given you are a newb to Vid ( as am I basicaly) I would HIGHLY reccomend just using the SLR you have for the moment untill you get a bit more into the learning curve and know what you want to do and IF there actualy is any work for this concept. It's far from the new thing Sprocket makes out.
As for the LED panels, I looked into them and quickly saw what a load of guff they were. I can get greater output and even better light coverage with 4 LED Car floodlights at a fraction of the cost.
With a little effort and even smaller expense, I can put a 12V battery and switch on the back of each one or pair them up with a common battery to use with a light stand. No way I'm going to pay the better part of a grand for what Dill pushes.
As for the variable colour balance, I can do that, IF I ever actually have call for it, with a bit of photo gell or as I have used for years on flashes, Common wrapping celophane. Just get something like yellow or blue and partially cover your lights till you get the colour you want. Isn't rocket science nor expensive.
But first of all, before you get carried away with thinking about gear, do your homework and find out where the potential markets are for this work in your area and if there is even enough to be worthwhile. Real estate agents are not the soft target Sprocket makes them out to be by a long shot.
As for his software that you upload the "E-Products " ( what a moronic name!) to his site to perform their miracles with and pay for each time, EVERYTHING he talks about like direct delivery to the client and templates etc can be done in Pro show and I'd bet my house that's all he's using.
With a little time and effort you can learn to do everything he talks about himself and can do it on the spot without uploading anything or paying every time you do.
The question is not wether you can do this work or what gear you need, it's really about is there any actual demand from paying customers for it. If not, then the rest is a moot point.