7 Steps for high-quality freehand Panoramas

This Article discusses the generation of Panoramas without usage of heavy equipment.

Feedback und Comments to salzamt@dativ.at are welcome!

 

 

The articles occasionally show such green Boxes. The text inside is meant to present more background information and is not needed for understanding the rest of the article.

Why shoot freehand?

A very important part of the magic of interactive panoramas is the possibility to be "in between the action". Mostly there is not much time to photograph an interesting scene. Time (and space) to setup your panoramic equipment will not be sufficient.


How to do it:

"Equipment"

Even when talking about doing freehand panoramas there is a clear limit on such a method. Scenes with very near objects need a very good guess of the nodal point. Otherwise a lot of rework is needed.
But you can use some lightweight supporting equipment as i do. You can see a photo of my monopod with a supporting "L"-Bracket on the right.

Also, try to use a small spirit level. You will get straight images with it and your images will stitch easier than without.

Take a quick look to the "360-Aufnahmen" (German). At least the images shall show you some other ideas to meet the nodal point.

 

"Outside"

Step 1: Know your equipment

You panoramas will not succeed if you don't practice the techniques before.

Before you start with your first freehand-panorama, do some tests at home to get a feeling of your camera and equipment. You will have no time for that when photographing your first "real" scenery.

  • Do a "test-pano" which also includes some near objects. Try to find out the optimal movement of your camera (and yourself) for rotating around the nodal point.

Step 2: Take a few moments of time to analyze your scenery.

  • Are the any groups of objects which are difficult to stitch?
    Try to avoid overlap of images in these areas. Avoid overlap in areas where near and far objects simultaneously appear.

  • Are the moving objects somewhere?
    Avoid overlap in these regions. Shoot an image twice if you are not sure.
    Try to shoot against the direction of the moving objects. This will help for not re-appearing in your panorama twice.

  • If under pressure when shooting: Shoot as much overlap as possible. If in question, shoot a region twice.

Step 3: Don't take too much time for shooting...

...but don't forget to fix exposure und white balance.
Afterwards, shoot an image of Sky and Floor (zenith and nadir).

"Inside"

Step 4: Set your control points mindfully.

  • Use control points with equal distance to the camera (this is meant in the original scene, not in the resulting image!)
    If not possible for the whole panorama, do it at least per image-pair. This will help the optimizer a lot to find a correct solution.

  • Don't forget to use control points of type "line".
    A tutorial about using "line" type control points can be found here.

  • Weight your important image-parts.
    Parts of the panorama which are crucial for correct fit can be enforced by using more control points than for other regions of the panorama.

Afterwards you can do your first run of the "optimizer". Only optimize x- and y-direction at the first time. Inspect the results. Delete unimportant control points that are far away and not so important. Now you can optimize again, including the rest of the parameters (rotation and lens parameters).

Step 5: Manually blend your images.

You will need an image-editing tool which is capable of layers (e.g. Gimp or Photoshop...)
Output your images as "multi-image TIFF", layered Photoshop or similar. Now you can cautiously blend the images one by one using the layer brush. Also use irregular patterns of the image to blend badly fitting parts of the image.

Step 6: Use your creativity

I bet you will not be able to fit all your image parts perfectls. So don't forget your creativity (and dont't forget if you are using equirectangular projection).

  • Cut out badly fitting image parts and move them. Because of panoramic projections this will only be possible for a very small image area at once.
    (Think of a railing where you may have to move some parts until the railing will become one)

  • To fill holes in the resulting image, you can use the stamp tool. This works good for trees or water.

Afterwards you can also correct your bad stitching errors by duplicating parts of the panorama as a new layer and use the layer brush to insert this part again at the correct position.

Erik Krause has descibed this method of Tom Striewisch this way:
Create your new layer from the background layer by copying it. Now swith off the underlying layer.
Paint by using the masking-mode (afterwards reverse selection) or layer-maska hole in the upper layer. This should make the unwanted part of the image disappear. Now switch on the lower layer and move it until the hole is optimally filled. Now reduce layers to background layer.
A lyer-mask has the advantage that it can be easily edited afterwards again.

 

Step 7: Don't try to be too perfect!

Most crucial is a good blending of important parts of the panorama. But only very few people will look at all parts of your panorama with the same attention and interest...