Introduction
One of the wrecks that I am writing about for “Aviation Wrecks of Southern California” is the F4D Skyray that crashed in the 1950s. The pilot, Leo J. “Pete” Colapietro bailed out at 650mph and living to tell the story. I had previously posted some great photos I recently received from a family member. On this dive I was working on a better photogrammetry model. The original model I created in Feb 2021 was okay but I was just getting started with photogrammetry. Also, the goal of the dive wasn’t shooting photos for that specific purpose.
NB – I also recently met with Pete’s eldest daughter and received a lot of great background information and more photos for the book. It is definitely going to be a great chapter. 🙂
The Dive
I went with Ray & Kyaa on the Sundiver Express up to Santa Monica Bay. It is quite a haul from Los Alamitos to get up there but we had good surface conditions and it was a great day. We got on-site and put down the line and the water visibility on the surface was nice with deep blue water we sometimes get in the winter.
The bottom conditions in Santa Monica Bay are aways a crap shoot. I’ve had days where it is 50 foot of visibility and days when it is 5 feet with basically the same surface conditions.
I got to the bottom of the line … and could barely find the wreck even though it was only 5-10 feet away. Definitely not a good sign and it shows in the results of the model (specifics below). The visibility was disappointing, but I made the best of it. A ton of photos were shot but it is very hard to keep track of location when your eyes are affixed to the camera. This is complicated also when trying to cover a 3D structure with photos. I was alone and could not see my strobe on the downline when I was at the farther reaches of the wreck.
When the visibility is that low, you need to get closer to the wreck. This allows the camera to focus on the structure and not particles in the water. This is especially true when video lights create reflections from the particles.
I made a couple passes around the wreck. After I got back to the section closest to the line, I waited and saw my strobe off in the distance and took a compass heading figuring that I could always just circumnavigate the wreck until I got back to that spot. After that, I could use a compass to get closer to the down line.
A short video clip of the dive is below (minus audio) to provide a sense of the visibility. At the start, you can see a round orange float from a fishing net. That was my marker to take a compass heading to get back to the downline which was only about 10 feet away but barely visible.
I ended up spending about 25 minutes on the wreck at just over 200 feet with a runtime of 100 minutes.
Photogrammetry Model
It is definitely a more true color rendering vs. the original which had the green tint, but there are sections that are missing. Particularly the “top” of the wreck. I don’t think I will go back and re-shoot it, but you never know. If any of my dive buddies would like to and help pitch in for the cost of the charter to return, please reach out to me.
Previous Model
New Model
The new model has some gaps and holes and the recesses are a bit blurry. This is due to not being close enough to the object when there is very low visibility. The colors are definitely better than the previous model but it isn’t what I wanted. The focus on quite a few of the pictures just wasn’t great.
You can clearly see the delta wing shape but there are blank areas and blurry areas which isn’t great
Conclusion
Disappointing to say the least but that is sometimes what you get in terms of visibility and conditions when you dive in Southern California. Maybe I’ll get back and try again…
