Rongnongno Loc: FL

Lower quality is all.

Grnway Loc: Manchester, NH

This is just an example, but I'll bet the same holds true for most, if not all, cameras that have this ability: I just happened to read some of the features of the new Canon 5D IV and still captures from the 4K video are 8MP. As has already been mentioned here, from a 30MP camera, you'll get higher IQ shooting stills.

rmalarz Loc: Tempe, Arizona

I guess it would be the equivalent of someone shooting a shot gun at a target and, if one of the pellets hit the bullseye, declaring oneself a marksman.
--Bob

SonyBug

A few years ago I attended a seminar (cost not free) and their preferred way of getting all of the wedding stills except portraits of the bride and groom were to lift them out of the video shot with DSLRs. They all looked great to me.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

Yes, no problem, just that your file, captured at 25 fps will be extremely small, probably not have much definition, contrast, density range, megapixel count, sharpness, etc. etc. etc. Other than these factors, you have got one fast camera there.

Coop1947

Sure does percent for online movies

jerryc41 Loc: Catskill Mts of NY

No problem at all. My son's Sony camcorder can shoot both still and action. Even when it's shooting action, it shoots dozens of random still shots. He now uses the camcorder when he wants stills.

dpullum Loc: Tampa Florida

Hay, as Jerry suggests, in our modern blurred world as with many thing they do multi things and the line between is blurred. Change the question to something non-photo graphic.
Is it OK to use my electronic controlled pressure cooker as a crock pot... tastes great.... but is it ethical. Ethics-Schmethics... who cares, if it works do it.

bcrawf

Frame rate is 25 fps, but what is the resolution?

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

An image is an image. Makes no difference how it was made of from what device it came from. As long as you made the image, the only thing that's important is the quality of that image. Any number of single pictures are taken from major films and used for advertizing those films. Post some of those pics from your videos. If you don't tell us it came from a video we won;t know.

JCam Loc: MD Eastern Shore

I'm another ! I have no interest in video recording, haven't even pushed the button or read the instructions. Why bother if you can get good shots with the high speed burst mode?

davyboy Loc: Anoka Mn.

Any different than removing trees from the scene or adding a moon to the scene they call it art but a photo?

insman1132 Loc: Southwest Florida

Start enjoying your new found option on your DSLR. You can have a lot of fun with it. And, you may end up with some "stills" you would not have gotten otherwise.

chapjohn Loc: Tigard, Oregon

I have seen the local Panasonic rep make a good still image for 4k video. Some BIF and sports photogs are using short 4k video to get actions still images.

Tomcat5133 Loc: Gladwyne PA

Hi! I have posted some thoughts about stills from video in the past. Art, fashion photographers were using Red cameras to pull stills for national and editorial content.
They are sometimes looking for some blur or motion as art. Or just capturing the precise moment. I edit stills and video and the best frame reaction may be on one from in 30 fps.

I shoot video and stills now. For clients I shoot with a Sony XDCam XAVC L and pull stills off of the video. Tweak a bit in photoshop and supply stills for PR. They love getting
them right after the video shoot. I do it in a primitive way. I load the footage into Final Cut Pro X latest version blow up the still I want in the viewer window and take a screen
shot from it.

I bought the Sony RX10 III for stills and video. Had been shooting soccer and sporting events. Ken Rockwell raved about the camera and said he has been using it
from the day he got it. He rates stills of moving subjects as 40% usable 30% so so 30% unusable. In video maybe 30% are usable.
That said for bigger resolution large prints and quality photography and the camera and lens and shooter that make a good shot.

As for most photographers not shooting video I don't think that really true. Rockwell admitted he shoots a lot of video. His secret.
I shot head shots for my son of employees in his office. And he said wow it is good to see a real camera and how good the shots are.
It was a Sony a7s with the great Zeiss 55mm. He was comparing that to cell phones. Well I saw stills and video in the NYTimes last week from Aleppo
and the tragedy in Syria. The reporter was shooting with an iPhone with an attached lens and had software that would allow him to set manually.
The pictures were great quality and well composed. He is talented.

So what point am I making. visualization is an art form. Open to pro's and amateurs to enjoy and use any acquisition technique.

Good luck.