LarvaeCam

June 6, 2006 1:12 PM

Webcams for shooting tiny critters: Any recommendations?

I'd like to set up an underwater webcam to observe how tiny (about 1 mm-long) marine larvae settle onto surfaces such as rocks or pier pilings. It is not crucial that the camera have good streaming quality. What is most important is for it to take a good, high-res picture of the animals at a nearby surface every few minutes. Any recommendations for a camera that might be a good candidate? I would also have to build or obtain some sort of underwater housing for it. Bonus points for suggestions on that.

posted by sotalia to Technology (8 answers total)

What are your light levels like? Most webcams don't work so well in the dim or dark, particularly not at high resolution. And what are your options for getting the data out? Are you going to immerse an ethernet cable in saltwater, for instance?

What's your budget? I'd recommend going pro for this, if you can swing the funding. Of course, it might be tricky leaving that exposed.

Anyway, I'd try an isight. They claim to have a short focal lenght, and have not-bad resolution.
posted by metaculpa at 1:56 PM on June 6, 2006

Damn you, fast typing! Lenght indeed.
posted by metaculpa at 1:57 PM on June 6, 2006

Response by poster: Hmm...good point about the light levels, metaculpa.

I haven't figured out how to get the data out yet. I was thinking that maybe if the cable came out of a well-sealed housing unit then it could be connected to a computer on dry land. I'm not quite sure about that, though.

The budget situation hasn't been ironed out yet, so I guess the cheaper, the better. I'll see if I can get my hands on an isight to try it out.
posted by sotalia at 2:29 PM on June 6, 2006

I am assuming from context that this is a settlement plate experiment of some sort? Is it crucial that you have web access to the camera?

I think the issue is going to be getting a camera that will allow you to distinguish the larvae. Once you figure that out, the underwater housing is pretty trivial. Sometimes the best thing to do is get something that's supposed to go underwater (like an underwater light) or just get an underwater housing intended for divers to use. You can seal any cable exit/entry points with silicone and/or epoxy.

(By the way, I am interested in what you're trying to do, since I am doing a study on the effects of salinity on species composition and abundance of sessile marine invasives...)
posted by nekton at 4:22 PM on June 6, 2006

Beware: Canon underwater housings cost nearly as much as the cameras (or I'd already have one). But the photos would be good. Not sure if those have an allowance for cables.
posted by Goofyy at 6:07 AM on June 7, 2006

Response by poster: nekton: Yes, this would be a sort of settlement plate experiment. It's not crucial that I have web access to the camera, but it seems that webcams (as opposed to regular digital cameras) are better suited for taking photographs on regular intervals. The underwater light is a good idea, though I fear that it might affect the behavior of the larvae (they might be attracted to it). Perhaps I could figure out a way to use one as a flash when taking the pictures. Your work sounds interesting too, and apparently we're neighbors. :)

Goofyy: Thanks for the heads up. I was afraid of that...
posted by sotalia at 8:19 AM on June 7, 2006

I need to clarify that I meant you could get an underwater light and use the housing to hold the camera. (Although that doesn't fix your "lack of lighting" issue...)

We apparently are neighbors! I assume you're in "WoHo" doing all this stuff...I left there not too long ago (I was at the MBL).
posted by nekton at 1:25 PM on June 7, 2006

There are a couple of cheap waterproof cameras listed in today's NYT - perhaps you could epoxy in the usb/power cables and run them to dry land? See here.

Good luck!
posted by metaculpa at 6:00 PM on June 7, 2006