Quick note about the photography experience and lessons I learned during the recent eclipse.
Starting with the basics. In order to capture good detail in the corona, you’ll need a long lens and solid tripod. Around the order of 500-600mm or so is good (on a full frame camera), you don’t want too long as the corona extends out quite far from the sun. I used my Tamron 150-600 and it worked beautifully, in combination with a 3-series Gitzo. If you wanted to focus on prominences, diamond ring or other smaller details you could use a longer lens.
Secondly, if you want to capture the partial eclipse (anything not in totality), you’ll need a filter of some sort. I’ve read ND filters are not ideal as they typically aren’t strong enough and stacking several just adds more layers and reduces the IQ further, plus not safe for viewing through an optical viewfinder (any SLR camera) since they aren’t ISO certified. A dedicated solar filter is the right choice here. However, a proper glass filter isn’t cheap and likely something you won’t get a ton of use out of so I avoided that route and instead made my own from scratch at 1/5th the cost with an astronomy-grade solar film (ND 5.0, ISO 12312-2:2015 certified, etc).
I mounted the film to the lens using form/poster board and the great directions outlined by Joe Cali. Process was pretty simple and straightforward. There’s also terrific information provided by MrEclipse/Frank Espenak on general eclipse information, including how to photograph.
As mentioned above, you’ll use the filter to photograph any partial eclipse, and then once totality happens you remove the filter quickly and shoot more. You have to be fast as totality is *quick*, certainly feels much less then the usual 1-2 minutes. I also tried to make sure I spent a few moments enjoying the experience rather then just playing with the camera the entire time. You’ll also need to bracket as the dynamic range of the corona is rather extensive. I think I ended up using around 9 different exposures merged together in Photoshop (details to follow). If you check out Frank’s exposure guide for solar eclipses you’ll see that different solar features require different exposures. I had a bit of difficulty capturing Baily’s Beads as they are very bright, change quickly and visible for a *very* short period of time (a few seconds right before & after totality), but managed to get something usable.
I also tried a wide-angle view with a landscape in the background and a composite image during the sequence. This was pretty trivial to do, as it didn’t require a filter or any special care (the sun occupies a small part of the image and really no different then regular daytime photography shooting into the sun). However, I didn’t do a ton of planned research on locations as I was more focused on the telephoto shots and the dried-up field I shot it in wasn’t particular interesting.
In terms of processing, the best method I found is similar to common techniques handling Milky Way images. Generally, you open the various exposures as layers in Photoshop, combine into a smart object then adjust the stack mode. Some massaging of the smart object in camera raw plus a curves layer or two should be all you need to get great corona detail. A friend pointed me as this video tutorial which helps summarize things rather well.
The image at the top of the post is a composite using this technique with a few modifications. I wanted to try making a composite eclipse image combining a solar with a lunar eclipse (using photos from a previous shoot) to bring up more detail in the moon itself. It took a little bit to balance things but think it came out fairly decent in the end. My favorite part of the images I captured were the prominences, there weren’t many during a period of low sunspot activity but being new to eclipse photography I was excited to see them in my images!
That about sums it up. The experience was awesome, in every sense of the word. I can’t wait to see another one in a few years!