fps override..

[sebolla74]

hi guys,i've some problem with fps override....i tried to get 50fps at 1920x1080 resolution but actual fps shows me 37,686 fps and i have to keep the shutter at 1\100 otherwise i get black band scrolling on the screen...any suggestion???

[1%]

That is as fast as it goes.

[sebolla74]

Thanxx...did you notice any difference in quality between 1280 50fps and 1920 25fps??i did a little test taking 2snapshot out from 2 shoots crop 100% and there is a big difference,the 1280 is worse than 1920...tomorrow it'll post them...

[1%]

Well 1080P vs 720P there is a difference. I'd be more sad if there wasn't.

[sebolla74]

I thought that 720 is just a sensor crop as the bitrate is the same as 1920...maybe the quality is different because the they put 50p in the same file size...what do you think??

[ilguercio]

I thought that 720 is just a sensor crop as the bitrate is the same as 1920...maybe the quality is different because the they put 50p in the same file size...what do you think??

[1%]

Its not a crop. 3x mode is a crop. In 720P the YUV buffer is only 1280x568.

[sebolla74]

Are you telling me that they use a different compressione??i'm quite worry because the my footages at 1280 get flickering a lot,specially if there are straight Lines or trees...and quality is poor like the 640x480...maybe i need to send the camera to the service..do you think magic lantern could cause it??

[Malcolm Debono]

Are you telling me that they use a different compressione??i'm quite worry because the my footages at 1280 get flickering a lot,specially if there are straight Lines or trees...and quality is poor like the 640x480...maybe i need to send the camera to the service..do you think magic lantern could cause it??

That's why you shouldn't record in 720p unless you need the higher frame rate. 720p has much more moire and aliasing, and it originates from the way the camera downscales the image (i.e. it's neither ML's fault nor is your camera faulty). Shoot in 1080p and downscale the footage in post if you want to output to 720p.

The flickering on the other hand might be solved by using a shutter speed of 1/(2*fps), so if you're shooting at 25fps, use a shutter speed of 1/50. This type of flickering should only occur under artificial lighting (i.e. not in daylight).
More info here: https://vimeo.com/forums/cameras_and_editing/topic:32466

[sebolla74]

That's why you shouldn't record in 720p unless you need the higher frame rate. 720p has much more moire and aliasing, and it originates from the way the camera downscales the image (i.e. it's neither ML's fault nor is your camera faulty). Shoot in 1080p and downscale the footage in post if you want to output to 720p.

The flickering on the other hand might be solved by using a shutter speed of 1/(2*fps), so if you're shooting at 25fps, use a shutter speed of 1/50. This type of flickering should only occur under artificial lighting (i.e. not in daylight).
More info here: https://vimeo.com/forums/cameras_and_editing/topic:32466

thanxx to reply.....i know that best shutter speed is double framerates and i was wrong when i said that i got flickering,it was moire and aliasing no flickering...but it seems to much to me...can you check this 2 footages out and tell me what you think about them??if you look at the straight lines on the footage at 1280 they are curving a lot....is that normal??thanxx again....

         

[adijiwa]

That's moire effect.

[Malcolm Debono]

Since it's a static shot, in this case I think that the curved lines might be caused by the lens' distortion. It's normal if you're using a wide focal length (such as 18mm). There's also more aliasing in the 720p version (look at the metal bar beneath the cooker).

[Datadogie]

Is the moire effect not due to line skipping.

eg.

1080p misses every other line.



720p misses three lines to every one.



At least that's how I see it.

[1%]

600D: Shoot crop mode through a wide lens. Probably no more moire.

[sebolla74]

Is the moire effect not due to line skipping.

eg.

1080p misses every other line.



720p misses three lines to every one.



At least that's how I see it.

hi thanxx to reply....i get what you mean when you say at 720p it takes 1 line every three,but i don't get what you mean that it misses every line at 1920....anyway it?s very bad canon issue(line skipping) at 720p....i did a test with a nikon d7000 and sony nex5 on the same set(my home...) and they don't have this kind of issue....at least you cannot notice it.....

[Datadogie]

If 18 mp works out at 5196 x 3464 how many pixels dropped are not needed to bring it down to1080 x 1920. This is where the T3i and its digital zoom eliminates the  moire as at only uses a section in the middle of the sensor. Thus less dropped pixels. I'm not sure how the 5d mk3 overcomes this someone here might be able to explain better than me