With Flare

Photography and Fine Art Digital Printing for the Beauty of It

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On March 20th I will give a workshop on stitched panoramic images. These are my notes for the workshop.

SPAO Workshop on Stitched Panoramic Images - Notes


1.      The Universe of panoramas

·        Cameras rotating on a special tripod mount with synchronized film advance

·        Mosaics assembled from prints physically – a la David Hockney

·        Full-sphere QVR

·        Recent 8x10 view camera shots, digitized and assembled, by Jeff Liao

2.      Why assemble an image?

·        Don’t have a fish-eye lens

·        Want increased resolution

·        Want increased span of image – a panoramic aspect

·        Want the distortion caused by rubber sheeting images together

3.      Getting the images

·        Check the light range of the entire panorama, choose your camera settings and turn off automatics

·        Choose a focus and set it

·        Decide on accuracy of pivot point

                                                   i.      If you can hold the pivot axis accurately to the centre of your lens’ focal point then there will be no parallax distortion

                                                 ii.      A panorama bracket or head must be used on a tripod to get a perfect pivot point

1.      Jim Watters’ site has design and construction details of a home-made bracket

                                                iii.      Hand-held can be done fairly well by pivoting on one foot without sliding it at all

                                               iv.      Hand-held can also be done loosely. Most of my landscapes were done this way

·        Decide how to deal with any movement that is in your panoramic field

                                                   i.      Moving people, animals & vehicles can be isolated OR included more than once

                                                 ii.      Moving clouds

                                                iii.      Waves on water are tough. I have occasionally succeeded but perhaps 10% of the time.

·        Overlap the images on significant details and always by at least 15%

·        Wide-angle lens will create severe distortion of space. Close objects will really get it!

·        Telephoto lens will show much less distortion

4.      The functions necessary

·        Rubber sheeting

·        GUI interface

·        Blending of luminosity and colour

5.      Software

·        Photoshop

·        Panorama Tools

·        PTAssembler

·        360DOF

·        PTGui

                                                   i.      Load images and create control points

1.      Auto-generate may fail and need some handwork. Go to Control Points tab.

2.      Check the resultant image for crucial attachment near edges of overlap

a.       It may be necessary to produce the pano and take it into an image editor for this. I haven’t found a way to do a fine inspection within PTGui. (“Show in Viewer” produces a lower-res image).

3.      Add points near the edge of the right (overlapping) image to control the edge.

4.      After you add points you must “Optimize” before the pano will be realigned

                                                 ii.      Panorama Editor

1.      Edit individual images – only when automation fails!

2.      Edit whole panorama

a.       Place center point

b.      Fit the pano

c.       Center the pano

d.      Straighten the pano

3.      Projections

a.       Rectilinear

b.      Cylindrical

c.       Equirectangular

                                                iii.      Create Panorama

1.      Image size

2.      File type

a.       Note that TIFF or PSD images are transparent around the edge of the pano, JPGs have the background filled in white.

6.      Workflow

·        Download from camera to <Date_Hour-Minute-Second>.jpg

·        Keyword tag all pano images with “PanoImages”

·        Separate pano images & move into the pano workspace in a source folder under the topic folder

·        Bring up PTGui and load a set

·        (After setting up the blended image) Save the created image in the topic folder, usually with the name: < Date_Hour-Minute_Pano >.jpg

·        Save the PTGui script file in the script folder

·        Inspect the generated files, perhaps remove extra black fill and print a contact sheet

·        For serious work, go back and correct any control point errors

·        Reset the size and file type for the use. After three detailed runs through my large set of landscape panos, I have gone to starting with the largest .tiff possible. If I want control of the overlay blending I choose layered .psd. Generate the image.

·        Do the Photoshop work

7.      The creative dimensions

·        Distortion of space: Strong, straight lines can be warped. Choose your pov and lens to enhance or minimize distortion

·        Projection:

·        Generate feathered, layered TIFF or PSD and work with the layers