Robbe Sea Wolf V2Posted by xilsoe May 16, 2014 20:05:36 Some time ago I got the waterproof case for the Mobius action camera. I hope to use it on my submarine this summer. Here are some pictures of it:
Robbe Sea Wolf V2Posted by xilsoe Sep 22, 2012 21:35:54 Last Sunday I decided to try out this angled Tic-Tac camera box I have been working on. I had been doing some more water tests, bud have not been able to find the leak I had in the first test. As of now I believe I had not put enough Vaseline on the lid.
Anyway I tried the Tic-Tac box out, and this is the resulting video:
I believe the water was clearer than last time I recorded submarine video.
As can be seen, using the air/water light refraction actually works and the angle I selected is useful.
Robbe Sea Wolf V2Posted by xilsoe Aug 25, 2012 11:43:53 As I mentioned earlier I want to try to angle the camera view a little downwards. To do this I am going to try out using the light refraction in water.
I did some theory on this in this post: http://heliblog.moller-ilsoe.dk/#post367. I wanted an angle of 30 degrees which means that the glass needs an angle of 39,9 degrees as mentioned in the post above. I don't believe I can make an angle that precise so I have made some approximations during the construction.
Here are some pictures of from construction:
The angle is made in 2mm polystyrene and the front is 3mm plexi glass. I painted the inside of the angle flat black to reduce reflections inside the camera house.
Currently I am testing the house for being water proof. That's why I put the nuts inside as shown in one of the pictures. The next thing will be to try it out with a camera inside.
Robbe Sea Wolf V2Posted by xilsoe Jul 11, 2012 20:44:22 As I believe I stated in my previous post I was looking into some mathematics to calculate the angle of the glass that should go in front of the Tic-Tac box.
After some thinking I derived a formula: angle = atan( - (1,33 * sin( desired_angle )/(1 - 1,33 * cos( desired_angle )))
To make it easy to calculate more angles, I made a python function. Here are some calculations results:
Wanted deflection angle
Not possible. Angle greater than 90
I may buy a Lazer to test the results above. One concern I have is whether the refraction will split the light into the different colours. Hopefully this will be negligible.
Anyway I'll try making a Tic-Tac box with angled glass and test it out to see if it works
PS: Note this will only work when the inside of the Tic-Tac box is dry and the angled glass on the Tic-Tac box is submerged in water!
Robbe Sea Wolf V2Posted by xilsoe Jul 10, 2012 19:29:19 The past weekend I went to Jutland for some visits. As I know Fussing lake is quite nice for running my Sea Wolf, I had brought it along. I also brought a couple of cameras with the intention of recording some video from the submarine.
I found that I was quite lucky. The weather wasn't too bad and fish were swimming around in the area I operated the submarine. Furthermore the water plants weren't growing too wildly so I could get close to them.
I made the first attempt on Saturday. The video filmed on Saturday all ended up being more or less Gray with no interesting content. From this I learned that the visual range in the lake is quite limited.
For this reason I decided to have another go at Sunday. At this time I mounted the camera below the bow of the submarine. This was to get closer to the bottom of the lake to reduce the distance as the visual range was limited.
I believe it had one other positive effect: It created shade in front of the camera so the sunlight wouldn't reflect from small parts close to the camera. I believe this increased the visual range for the camera.
Here is the video I made from the recordings:
The fish seen in the video are perch.
I have one improvement in mind, that I believe will make it easier to create video recordings with interesting content: The camera should be pointed downwards.
Some time has been spent on figuring out how to do that. I would prefer not to modify the submarine too much and have easy access to the camera. Here is what I have come up with: I will try putting an angle on the Plexiglass on the enclosing Tic-Tac box and use the refraction of the water to make the camera look downwards.
This will allow me to mount the camera in the same way below the bow using a rubber band and still give me easy access to the camera.
I am currently studying some mathematics to figure out the angle of the Plexiglass for the Tic-Tac box.