It's not a se

ssrdd said:
According to kenrockwell

D800

36MP FX (35.9 x 24.0 mm)
Video only uses a central 32.8 x 18.4mm section of the sensor, at most.

I thought it shoots just like 5D, and uses maximum sensor size, this is little disappointing in video mode comparatively 5d mk3.

does anybody noted this before?

It's nothing new, it's described in the manual! The picture in the manual is the same as the picture to the right on this page: http://photo.vanderkolk.info/photo-nikon-d800-moire-antialiasing-artifacts.php According to Nikon specs the movie mode uses about 91% of the sensor.

The technical background is not explained in the manual, but it's not too complicated. You need a number of pixels that is dividable by 1920 to make downsampling easier, and crop back to a 16:9 format.

Hi,

I don't have the D800 nor the 5D, but have envy. ;-)

Video's aspect ratio is 16:9, so reapportioning real estate would have to happen anyway to use all the information in each pixel, you wanted to resample the pixels, which isn't something I would want to do. Resizing the amount slightly from the chunk available makes a bit more sense.

While 35x19 sounds ideal, my guess is that engineering plays a huge role in the art of the doable, assuming that Rockwell's information is accurate.

Finally while the 5D might use the breath of the whole sensor, it, too, is cropped to meet aspect requirements, and but only a third of the lines available are sampled for video. I don't know how Nikon does their sampling. We might find out they discard lines in the sampling process, too.

Keep in mind, high definition video is just 1080x1920, the camera isn't going to put out more than that so it would have to be sampled down, there is a lot to lose and still look terrific.

My best,

Mike

Hyphen said:
That is still most of the sensor, and it seems pretty easy to check (if I understand correctly, someone please correct me if I'm wrong).

I don't have one, but there should be a noticeable horizontal crop comparing a still from a video to a photo. (obviously there will be vertical crop at a different aspect ratio).

Also, you aren't really "losing" a stop, you're losing angle of view. It sounds like a crop mode. You don't lose stops by using DX.

That is still most of the sensor, and it seems pretty easy to check (if I understand correctly, someone please correct me if I'm wrong).

I don't have one, but there should be a noticeable horizontal crop comparing a still from a video to a photo. (obviously there will be vertical crop at a different aspect ratio).

Also, you aren't really "losing" a stop, you're losing angle of view. It sounds like a crop mode.

No doubt Canon still have the upper hand in video, but Nikon is rising. And do take note that you're losing less than 1/3 of a stop for shooting the central 32.8x18.4mm of the sensor. So no biggy for a good sensor like D800.

According to kenrockwell

D800

36MP FX (35.9 x 24.0 mm)
Video only uses a central 32.8 x 18.4mm section of the sensor, at most.

I thought it shoots just like 5D, and uses maximum sensor size, this is little disappointing in video mode comparatively 5d mk3.

does anybody noted this before?