How to Create a Solar Eclipse Phase Composite Image

Most of those who photographed the solar eclipse captured images from the beginning until the end, from C1 through C4. While every one of those images may be intriguing, showing all of the stages of the solar eclipse in the same image can take the intrigue to a new level. So, plan on creating at least one solar eclipse composite image. Fortunately, the process is easy. Here are the steps necessary:
 
First, visualize the composite image you want to create. In this case, I went with a single row, but curves, multi-stacked rows, etc. can also work well. Consider searching for results others have created, or just let your imagination go wild for a completely new take on this event.
 
With a design in mind, select the individual images to be included. You likely want a near-equal time period between the partial eclipse selections and that means breaking out your math skills.
 
Use the EXIF information in the images you captured to determine the precise time of totality (or maximum coverage within totality) (or use a reference to find this information). Then look at the capture time of the first image you want included. This gives you a timespan that can be divided by the number of partial eclipse images you want included on either side of totality/max. Select images captured at each of the timespan milestones you selected. Having equal time periods between images is not a rule and I veered slightly from it in my example (partially to avoid some clouds encountered).
 
To cleanly merge into a black background, each image being included in the final composite should have a completely black perimeter. While partial eclipse images most likely already have this attribute, a tightly framed HDR image of totality may not. An easy way to darken the border of these non-conforming images is to darken the darks. Adjust levels or curves to make the dark colors darker until they turn pure black along the entire perimeter.
 
Each image being included in the final composite should be cropped relatively tightly. This facilitates image position adjustment in the composite image without having frame borders overlaying lower layers.
 
Next, the images should be loaded into layers in Photoshop (or a similar app). I use Adobe Bridge for this task, browsing to the folder the files are located in, clicking on the first of the series and shift-clicking on the last to select them all. Then select the "Tools" menu, "Photoshop", "Load files into Photoshop Layers ..." and a new Photoshop document will open with all of the images stacked in layers.
 
Once all images are loaded into the PS file, they will likely be stacked directly on top of each other with a canvas size equal to the largest individual image loaded. So, the next step required is to increase the canvas size (press CTRL-ALT-C) sufficiently to hold the visualized layout. Don't worry if you get this setting wrong as it is easy to further increase the canvas size or crop the image later. My preference is to go big and opt for the crop.
 
The increased canvas size results in insufficient border color with the newly added space likely being transparent. This is an easy problem to fix. Create a new layer (click on the new layer button at the bottom of the layers palette). Select the paint bucket tool (press G, or SHFT-G repeatedly until the paint bucket is the selected tool). Then change the selected color to black (press D, then X). Then click anywhere on the canvas with the new layer selected. That entire layer will turn black. In the layers palette, drag the new layer to the bottom of your layers stack to make it serve as the background.
 
Next, move the image on each layer into place using the move tool (press V, or SHFT-V repeatedly until the move tool is selected). After selecting the layer to be moved (turning off the move tool's auto-select feature might be helpful), drag it into place. Repeat Consider using a grid (View > Show > Grid) with the grid size adjusted (Edit > Preferences > Guides, Grid & Slices...) to something that works for you to help with the alignment process.
 
Massage the design as desired and then publish it to the world. Consider creating multiple layout designs as most of the work has been done at this point and new designs require only minimal effort. Simply drag the layers around as you like, saving a new version of the file each time you create a design you like.
 
While I had three complete camera setups in operation during the eclipse, it was the Canon EF 600mm f/4L IS II USM Lens-based setup that I relied most upon. When I need the most focal length possible, this lens is my go-to option. Yes, the 600 f/4 is big and expensive, but the combination of the impressive image quality it delivers and the frequency in which I use it makes the cost a good value to me. In this case, I relied heavily on the focal length and image quality attributes as a 2x Extender will magnify any aberrations present and there were already enough of them between earth and the extreme-distant subject.
 
Back to the main point of this article: make the effort to create some composite images and you will be rewarded by the results. It has been over a month since the 2017 total eclipse event captivated us, and simply looking back into the images captured on this day will bring back great memories, helping you to re-live that rare experience.