Upgrade for Stereographic projection

[Matej Mlakar]

Hey, so here is a continuation of a conversation I had a while back with Joost.

A quick recap: There is an annoying problem when creating 360 Milky way arch panoramas in basically any panorama software on the market. No matter what projection one selects, there will always be some kind of distortion going on. 

The best projections at the moment are "Stereographic", followed by "Mercator"  

  

Stereographic is almost, and I mean almost perfect. The problem with this is when one is working on a 360 image, the edges are getting stretched more and more in a non-linear way.  

  

I was wondering if it would be possible to add some kind of slider, similar to what Cylindrical projection has, where we can then adjust the compression?  

  

Basically it would bring the edges from left and right of the image back towards the center and we would completely remove the stretching. The only way I see to solve this is by creating some sort of empty space, so what in 3D space would be behind us, would be empty and the panorama would not be a complete 360 image anymore, but that is alright as long as the stretching gets removed. 

  

I hope I described everything to be at least a bit reasonable, as it is a bit difficult for me, because I am not a native English speaker.

Kind regards,

Matej

[Erik Krause]

Am 26.09.2024 um 10:16 schrieb Matej Mlakar:

> I was wondering if it would be possible to add some kind of slider,
> similar to what Cylindrical projection has, where we can then adjust the
> compression?

Stereographic has a compression slider (at least in v12 and v13).
However, you can not project the sphere which is around us onto a flat
surface without some kind of deformation. But what exactly do you want
to achieve?

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

[Matej Mlakar]

I would like to remove the stretching on the edges, for example: https://imgur.com/oAjZ4t9 

Here you can see that the panel 1 and 12 are heavily stretched and it kinda "ruins" the pano

https://imgur.com/oAjZ4t9 https://imgur.com/oAjZ4t9

četrtek, 26. september 2024 ob 21:04:52 UTC+2 je oseba Erik Krause napisala:

[PTGui Support]

Have you tried the 'fullframe fisheye' panorama projection in PTGui?
This is an equidistant projection.

For the middle of the panorama this resembles stereographic, but it
doesn't stretch the edges like stereographic.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

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[Matej Mlakar]

FF Fisheye looks like this: https://imgur.com/00Nta1i

it stretches the pano upwards, which is visible as very deformed region around Milky way core and edges do get lost a bit.

https://imgur.com/00Nta1i https://imgur.com/00Nta1i