Is there a technical term for a tilt all around the panorama?

[ChameleonScales]

What do you call a vertical tilt all around a 360° panorama like this:

A program I use calls it pitch but that's obviously incorrect, since a pitch would actually look like this:

Note that I'm not asking how to perform this transformation in Hugin (yet), I would just like to know if there is a term for it in the "panorama-makers" profession.

[Bruno Postle]

I think we would call this vertical shift.

--
Bruno

On 24 May 2020 23:41:51 BST, 'ChameleonScales' wrote:
>What do you call a vertical tilt all around a 360° panorama like this:
>

>A program I use calls it pitch but that's obviously incorrect, since a
>pitch would actually look like this:
>

[Donald Johnston]

Vertical shift sounds more like what a camera on an elevator would do.

[David W. Jones]

In the "yaw, pitch, roll" world, wouldn't this be pitch?

On 5/24/20 4:59 PM, Donald Johnston wrote:
> Vertical shift sounds more like what a camera on an elevator would do.
>

> On May 24, 2020, at 5:26 p.m., Bruno Postle wrote:
>
> I think we would call this vertical shift.

--
David W. Jones
gnome...@gmail.com
wandering the landscape of god
http://dancingtreefrog.com
My password is the last 8 digits of π.

[Sean Greenslade]

On Sun, May 24, 2020 at 10:41:51PM +0000, 'ChameleonScales' via hugin and other free panoramic software wrote:
> What do you call a vertical tilt all around a 360° panorama like this:
>

> A program I use calls it pitch but that's obviously incorrect, since a pitch would actually look like this:
>

> Note that I'm not asking how to perform this transformation in Hugin (yet), I would just like to know if there is a term for it in the "panorama-makers" profession.

Technically speaking, they're both pitch. The difference is in what is
being "pitched".

In your first example, the panorama is stationary and the viewer /
camera is having its pitch altered.

In your second example, the panorama itself (assuming a spherical
projection) is being rotated. Assuming you're using the viewer / camera
as the axis reference for this rotation, it would also be correct to
call this a pitch rotation.

If you can describe what you're actually looking to achieve, we might
have better insight. For example, the first animation shows the effect
of cropping the top and bottom of an equirectangular panorama.

The second animation is a little confusing since the grid seems to stay
locked to the camera, but assuming it's just projecting a camera-space
grid onto an invisible spherical panorama that isn't moving, this can be
accomplished with the pitch control in Move/Drag tab of the Fast Preview
window. Hugin's model considers the virtual camera to be still and the
panosphere to rotate around it, but the result is functionally
identical. If you're looking to just capture that center band, you could
reduce the vertical FOV to suit.

--Sean

[Abrimaal]

Why not X,Y,Z? Before using Hugin I did not know what yawn meant.

[ChameleonScales]

Thanks everyone. I find it rather surprising that such fundamentally different transformations would have the same name.

If it was up to me, I think I would call the first one "conical tilt", since in that situation, the camera's center axis describes a cone instead of a disk when rotating horizontally.

Anyway, right now the reason I'd like to know the terminology is that I'm writing code for a Blender add-on (made to work with Hugin's output) and I'd like to get my names right.

If there's no official term or if they're both officially called pitch, then I'll just come up with my own name.

[ChameleonScales]

Sean: Yes, the pitch in my second animation corresponds to the pitch in Hugin's Move/Drag tab. To me, that's the only thing that should be called a pitch.

About this grid confusion you have, the camera is moving with the grid because in this case it shows what happens if you take the photos on a tilted tripod (the animation frames just show various tilt angles), but as far as I know, that would still be called a pitch, only one you had a capture time.

At least I hope the terminology doesn't change depending on whether we're talking about the capture's orientation or the panorama's transformation because I would find that logic really confusing, since the capture process can involve all the same orientations as the transformations you can apply to compensate for them.

[ChameleonScales]

*at* capture time.

Sorry. Darn non-editable emails.

[Erik Krause]

Am 25.05.2020 um 10:24 schrieb ChameleonScales:

> I find it rather surprising that such fundamentally different transformations would have the same name.

No, since it's the same what you do to the camera: You pitch it. In the
first case you pitch the camera alone, not the vertical axis, in the
second case you pitch the vertical axis.

However, if you want to extract a partial image like in your first case
you'd need a different transformation. The resulting image would be
formed like an arc or like a circle. There's a brief outline on the
panotools wiki where you can get the idea. It's for PTGui but should be
transferable to hugin:
> https://wiki.panotools.org/Unusual_remappings#Orientation_plate_.28arc.29

--
Erik Krause

[ChameleonScales]

However you want to put it, it seems the panorama language is missing a word to differentiate those 2 ways of orienting/transforming a panorama. That's all I wanted to know for this topic.

Thanks for your help so far

[Donald Johnston]

X Y Z is just translation without any pitch, roll, yaw. After a translation the camera is still pointing along the same parallel path.

D Johnston

[Erik Krause]

Am 25.05.2020 um 14:46 schrieb ChameleonScales:

> it seems the panorama language is missing a word to differentiate
> those 2 ways of orienting/transforming a panorama.

One operation on two different objects. Pitch camera vs. pitch panorama.
No new words needed.

--
Erik Krause
http://www.erik-krause.de

[ChameleonScales]

Ok I concede, that's a good point.

[Abrimaal]

Some 3D objects editors use both X,Y,Z translation and X,Y,Z rotation.
Translation is by pixels, cm or other units, rotation is by degrees.

[ChameleonScales]

Just some gifs to show why I prefer to call them "conical pitch" vs "disk pitch" to avoid confusion :