aspect ratio

[stefanocps]

it s not premiere specific but you might still help

I notice that somethimes some clips looks like if the aspec ratio it is slightly different..images tends to be slightly larger than tall..i don't know why and when it happen but somtimes i notice these faces that looks like larger than normal

I use a fuji xt3 with lens zoom 18-55

thanks for help

[Ann Bens]

Moved to video lounge.

[Richard van den Boogaard]

I guess you're discussing the nature of how lenses work in relation to the distance to you subject, in combination with the size of your camera's sensor. I don't know what type of sensor is inside the Fuji XT3, but I assume it's either S35 or M43rds. Only full frame will translate normally into the focal length you read on the side of your lens. 18mm means wider view, thus wider faces, while 55mm is more compressed (at the same distance to your subject). Please look at this video on perspective distortion: https://www.youtube.com/watch?v=_TTXY1Se0eg

If this is not what you're experiencing, please clarify. Otherwise, hope it helps.

[stefanocps]

It looks like that is the problem. sensor is an.aps c. So what should be the solution to avoid that?stepping back and crop or use zoom?sometimes it s not possible to step back...chamge aspect in prmier slightly adjusting the ratio could be a solution?

Thanks!

[Richard van den Boogaard]

The sensor size says nothing about the aspect ratio you choose to shoot in.

APS-C is comparable to Super35 or about a crop factor of 1.6 compared to full frame glass.  I believe APS-C's crop is 1.5, actually. Thus, a 16mm full frame lens will act like a 24-25mm on a Super35 sensor, and so forth.

[EuanWilliamson]

Hi, please see this image from the Fuji specs for the camera.

from: https://fujifilm-x.com/global/products/cameras/x-t3/specifications/

There is a HD option that may be the issue.

You said that some clips show the problem. Could you be shooting in this mode?

Feel free to reply with a small sample of one of the clips that have the issue.

[Richard van den Boogaard]

The 2048-1080 pixel refers to a cinema aspect ratio. Most films in theatres today are shown at 2k size, which is this aspect ratio, or 17:9 instead of 16:9.

Either accept the extra (unused) pixels on both sides of the frame (or use it for reframing in post) or switch to the FullHD 1920x1080 mode.

[stefanocps]

of course i did not shot at 2048x1080, but 4k and edit in a 2k sequence. Also, as i said, this "effect" it is not so evident, some don't notice at all, others, that are more critical to their shape, notice that quick. Also it is only in some shot, not intended different "format" shot...but takes", position, framing..or similar

I wrote about the sensor becuase you (Richard), ask about that

I think, as that video showed, that it must be somehting related to perspective distortion

[EuanWilliamson]

Glad to hear it 🙂 

You hadn't said earlier what the clips were.

Still, post us a small clip of a file with issues please with a description of what you feel is wrong.

[stefanocps]

this video i can notice that the doctor face is larger than what normal is

https://www.youtube.com/watch?v=R04MaQRUv9I&feature=emb_imp_woyt

she never said anything but i can see somehting weird

again..it is not suche a big things to see but there is a slightly change in poportion, resulting in larger face..a real low amount

i never really notice before, but in my last video(it is not posted yet) the persone said that she looks larger than ususl..and i can tell that may be she is right..may be...

[EuanWilliamson]

Thank you.

That's a ~12min video. At what time stamp do you see the effect most?

Again, please attach a small ~5 second section of the original camera video file so we can check it technically.

[stefanocps]

almost everywhere, jut check the first 10 seconds, the woman speaking

[EuanWilliamson]

Hi, I'm sorry, I give up here.

I'm trying to help and I've asked you three times for:

"please attach a small ~5 second section of the original camera video file so we can check it technically"

We're all volunteers here, not paid.

[stefanocps]

Sorry, why you want it like that, for download it? I fid not understand that...i ll do it tomorrow 

[stefanocps]

https://www.stefanocapasso.net/test.mp4 

here you can download the video, few seconds

[Richard M Knight]

Without knowing the doctor it's hard to see any thing wrong. Try filming a circle and measuring it on your monitor.

[EuanWilliamson]

If this is a piece of camera original and not something that's passed through an editor

then the aspect ratio is identical.

Here is a comparison between the camera file and what's on YouTube.

I've used the power plate as a reference.

The two image grabs, one from the camera and one from the YT vid are sized only and then composited.

They are identical and there is no aspect ratio change

[stefanocps]

as i said i never think that the ratio was changed..but when the subject started to tell me...i started to doubt, and i tried to undertsand more to be sure of what i was doing...so..this can enforce my confidence

thanks

[EuanWilliamson]

Well now you have proof you can show them 🙂

[EuanWilliamson]

One last thought came to mind.

It's possible that it's to do with how they are watching the video.

Would they be capable of taking a screen grab of that part of the video that shows the power plate?