2 shot Bubble panorama creation using PTGui

Start PTGui

This is the final panoramic image after the 2 layers have been merged in the graphics package. This image is the used by the panoramic viewer of your choice.

Left: Sky shot from the ground. Trim excess black area and crop to square.Right: Aerial shot looking down. Trim excess black area and crop to square. Try to get an image where the sky/ground produces concentric areas. Both images must be of the same size and proportions. Any slight size difference can be adjusted in the graphics package using the sky image. Use the ground image as the datum image 

These images show what we will end up with once we have processed the circular images in PTGui.

1.Load images….

Please read notes.    Screen shots are for the Mac program but the work flow should be the same in Windows. Notes on navigating the program simulation. Each page has a link to the next action an example of which is the load images button above. They are always green. Each has a info/instruction panel identified above by being in a bluey box.  i.e. Click Load images. To navigate back each page has a back button at the top of each page.

Click Load images………..

Back

Open

Open your chosen image………..

Not required for our use.Cancel Camera/lens data

Cancel

Advanced >>

Click Advanced >>  to reveal more tab selections above.Leave data below as is for now.

Click Dropdown box to reveal more lens types and select  Circular Fisheye.

Rectilinear (normal lens)

   Circular Fisheye

Click Circular Fisheye to continue.

Source Images

Change Hor. Field of View: to 180 degrees as done.Then click Source Images tab above.

Nothing to do here.Just check you have right image and the size is correct. i.e. square and cropped. Click Lens Settings tab above.

Lens Settings

Nothing to change here should be as shown. Then click Panorama Settings tab above.

Panorama Settings

Select highlighted projection.

   Equirectangular (for spherical panoramas)

Crop

Change Field of view to 360 x 180 as shown.Then click Crop tab above.

Continue

PTGui should automatically pick up the circular image as highlighted by the dotted line.You can however alter the radius by clicking and dragging the line or just selecting the circle and move in it's entirety. Click the button below to show.

As you can see the dotted line can be sized and moved.Click button below to continue

Image Parameters

Nothing to do here.Click on Image Parameters tab above

This shows the current state of the image. It is basically a square. This will change if you are successful in "flattening" the image out.We shall return here following on from using the Control Points and Optimizer. Click the Control Points tab above.

Control Points

    Horizontal line (---t2)

Here you can see 2 images (both the same). You can if you wish for greater accuracy use the Zoom. But before we do ANYTHING on this page we must SELECT the CP type and set it to Horizontal line. Otherwise all the work you are about to do will be useless.Select Horizontal line to continue.

Ordinarily we would be creating control points between 2 different images here. However we only have one so we are going create an horizon from the control points we add by following one selection from the left hand image and moving a few degrees on in the right hand image. You already see that PTGui has reflected my left hand selection in the right hand image by the cross. Once I click the left selection PTGui will automatically highlight the right hand selection but we will confirm by going to the right hand image and selecting a point on the land horizon 10 or 15 degrees further round in a clockwise direction.

As you can see by moving the cusor over to the right hand image our intended control point is reflected by the white cross in the left hand image but a further few degrees on.  We accept the selection and move back to the left hand image selecting a point further on from the one we have just confirmed and so on until we arrive back at our first selection on the left hand image. DO NOT over lap the last control point with the first.Click continue to see the full selection. 

For the sake of clarity and speed I've only put in a few control points. Remember you can zoom in on the image and put more points in more accurately on the land/sea horizon. But you can clearly see the progression of the control points around the images in a clockwise direction.Click Optimizer to continue.

Optimizer

On the Optimizer page leave settings as they are and just click Run Optimizer. To continue click Image Parameters.

The warped image now should have changed from a square to a flattened rectangular image.Note: Sometimes the image appears the right way up and sometimes inverted. There's much maths going on here, haven't got a clue why this happens. The image can always be righted in the graphics package  :-))

The other tabs Exposure/HDR and Project Settings can be left as is. Click the Preview tab to continue.

Preview

Create Panorama

The Preview image size is automatic. On a Mac you will see a low-res pano in Quicktime viewer. Not sure what you get in the Windows version.It can't be saved it is just a preview. Click Create Panorama.

Choose your settings here. I set the Optimum size to the Maximum size. Usually jpg and Blended Panorama.Leave PTGui to do the stiching and leave the Output res: on 300. Click Create Panorama

Not the image in the previuos pages but you can see the flattened image. We repeat the process with the sky image then using  a graphics package using layers the sky and horizon are blended by you to produce a full image. Some people have a stock library of skies ready to add to their panorama. The next image shows a stock sky. You do have to do a bit of splicing and fudging to get the orientation for the sun, shadows etc. But it's quite easy just to copy the image and move it along, so long as you get it pixel perfect in the joins. I use Photoshop as my graphics package.

Full Image

Using a stock sky image

Using on the day sky image