Friday, June 3, 2011

Tow Cam Blog

June 2nd

The WHOI Tow Cam is a multiple instrumental package mounted onto an aluminum frame. Along with the two separate camera systems there are: Niskin Bottles for water collection, altimeters for altitude, standard CTD (see Tina’s post), batteries, data link, lasers for a measurement scale, and a whole lot of wires! The primary use of this sled is for underwater photography. Attached to the frame are two cameras that have the ability to record over 4000 images on one tow alone.

One camera is called the DSPL, the other OIS. The DSPL produces an image with a large footprint. The OIS produces an image that has 4 times the resolution than the DSPL but the footprint of the image is much smaller. Another ingredient to this camera system is the data link, which gives us the ability to see the pictures in real time on a monitor. The data link provides ethernet up the sea cable. Which makes the camera operation exciting and fun for everybody!

Each camera is set up to take pictures at 10-second intervals. Tow Cam operations can only happen when conditions (weather) are ideal. If the ship’s heave is too great we run the risk of “crashing” the frame and cameras on the bottom. If the winds are too high it’s difficult for the ship to hold position for deployment and recovery. And this is a risk we are NOT willing to take!

An average deployment and recovery time is about 6-10 hours. During this process another member of the science party is plotting the ships position, speed, depth of frame, and altitude every 5 minutes. Once the frame is on board, the pictures are downloaded from the cameras and backed up, which could range from an hour to five, depending on how many pictures are on the camera and how well the coffee has been flowing that day.

Luckily, both ships crew and officers have been unbelievable at handling the ship during operations, and controlling the over the side operations safely so we can optimize our time with the science (And there is a lot).

When I said “TOW CAM!”, NPB 11-03 participants said:

“Yea, Lets Do it!”… “Don’t stare at the lasers”… “GO CAM”… “live feed from Tow Cam is awesome”… “far out images”… “what I have seen is pretty cool, watch for hours, plotting lots of locations”… “brings up a lot of water”… “makes me think of my friends in the hydro lab”… “cool to watch deployment and recovery”… “mind blowing images”… “exciting to see what undisturbed habitats and life looks like 3000 meters down”… “it’s heavy”…“useful”… “crisp”… “weather”… “Bonanza”… “awesome”… “cool”… “lots of water”…“take it back out we need to rinse it off”…“amazing advancements in supportive science”… “fun seeing the real time imagery”… “backing up lots and lots of pictures”… “Daffy Duck”…“lots of logging and pictures”.

NBP-11-03 thanks for a great cruise!

By Ben

Weather: temperature 35 °F, windchill 15 °F, wind speed reducing to 10 knots, sunny intervals

Skip, Sandy and Ben deploy the Drop Cam, another type of underwater camera system (R. Waller).
The Tow Cam being deployed a few days ago (R. Waller).
Ben and Marshall in the hydrolab, looking at some Drop Cam photos today (A. Margolin).
Bonanza! David and Ben playing a card game to relax after a long day of work! (A. Margolin).
Andrea celebrates after bringing up her first dredge (M. Swartz).