Affinity Photo: FishEye Lens Correction complexities

[MartinMHC]

Hello
I have a panorama image created by Affinity Photo (v1.7.1) which has produced a panorama (see below).

This panorama features a Fisheye effect that needs to be removed (or minimised at least). I have previous experience with Jasc Paint Shop Pro which did a VERY good automated effect of doing this, but I cant get the correct results using Affinity Photo.

I have read similar topics on here and explored the Developer Persona and used the "lens" tab and tried to adjust the distortion, however, the distortion works on the whole image regardless of focus. points.  This means that the centre of the image is reduced and set to appear further away (shrunk) whilst the same applies to the outside of the image, simply  to a lesser extent. 

What I am looking for, is a system that sets a magnitude effect ring (usually 50% of the radius of the image)  where by the image data within a range of this "ring" is not adjusted, data outside of this ring is pulled towards the viewpoint, whilst data inside this ring is pushed away (as fish eye reduction). 

An example image is below. smaller-Intention

See The full image (16:5 ratio), see the red inner ring, all the image dta within that ring I want to be fish eye adjusted to be pushed away from the viewpoint. however, between the red ring and the yellow outer ring that image data shouldbe only minor ly adjusted as a zero point band, with the image data outside of the yellow  ring being pulled up towards the viewpoint.

In effect, I want to try and not just negate the fisheye effect but to actually invert the fish eye effect.

Using the lens distortion effect only drags image data inwards and makes everything shrink without bending the relationship; please see the centre wall (within the yellow circle) is still bulging despite being heavily distorted (-50%). Please see the black arrows indicating that data on the periphery of the image is also being dragged inwards when that actually works against what I'm trying to achieve. 

Fish eye is at best only part of the solution.

From all I've written, can anyone advise the name of the process that I can use in Affinity Photo OR Designer (I have both) to adjust this image in the way described.

Image is created from a panorama of 5 images and is sized at ~11.8k x ~3.8k.

Thanks, and apologies if the answer is a simple function I'm unaware of!
 

[HVDB Photography]

Did you try the Perspective Tool ?

Start with the Dual Plane and drag the middle nodes inwards ..

[MartinMHC]

Hello @HVDB Photography,
Thanks for the help.
Yes I did try the perspective tool, however that seems to run on straight lines, single pane it doesn't work but double pane has some positive effects but due to the centre points, this leaves the centre with a notable hick where the two panes (with their own perspective distortions) now meet -- for intance the topof the wall above the car is straight on the RHS but then on the LHS suddenly vears up.

Actually you give me the idea to apply the Perspective tool after the fish eye cancellation effect. I will give that a shot.... cheers

Update: Working with Perspective tool and fish eye caused straight line interruptions on the centre area of the image -- doesn't work well. 

Edited July 27, 2019 by MartinMHC