I thought it be interesting and perhaps useful for others considering what type of DSLR and what focal length lens to use when contemplating options for solar photography.

These are two images taken from two different DSLRs at about the same between first and second contact shot in RAW format. These are the images straight out of the camera, though I horizontally flipped the first image (Version A) to mimic the orientation of the second one, which was at a different orientation on a German equatorial mount.

The top (color) image in Version B  was obtained with an astro-modified Canon 80D with a Samyang 135 mm prime lens set on a Sky-Watcher Star Adventurer GTi star tracker at solar rate.  This was shot at ISO 200, f/8 and 1/5000 sec. The disc color was apparent on the camera LED screen depending on exposure parameters, and easy to see in Lightroom. The underlying mouseover image (Version A) was shot on a conventional Oben tripod with a stock Canon 90D and a Canon 75-300mm zoom lens set at 300 mm.  In pretesting in the weeks leading up to the eclipse, it was nearly impossible to tease any color out of the disc regardless of exposure parameters. This was shot at iso 200, f/13, 1/3000 sec.

I had to chose one camera to image with during totality, and chose the modified 80D with the prime 135 mm lens because I knew (from practice) that I could remove the solar filter without disturbing focus; that was certainly not the case with the zoom lens.  In retrospect, I wish I had put the stock DSLR with the prime lens, rather than the modified DSLR; I think the stock DSLR would have been better for totality, as all of my totality images have the same orange hue to the corona, which, though beautiful, is not as clean, perhaps.  

I think the 300 mm focal length with a cropped frame sensor might be the ideal balance between focal length and wiggle room for framing trying to capture a widely dispersed corona - at an effective focal length of 450 mm, I think this would have been comfortable to obtain appropriately bracketed totality shots, like @Brian Valente's amazing shots.  That is what I was hoping for!  Not sure what I did "wrong" setting up my 7 shot bracketing parameters, but I think I just ran out of time shooting at enough f stops.  I must admit, I stopped taking pictures for a bit during totality and just soaked in the view.