Author Topic: CrabCam  (Read 18267 times)

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #30 on: May 01, 2012, 14:27:00 PM
It's interesting stuff alright, though I suspect it'll end up like when I wanted to make a budget trail camera using a webcam and DVR. Once you have bought the camera, power source, recording media/hard drive, waterproofer (housing/bag etc) and required cabling, it ends up costing more than the already expensive commercial solutions!

I know that a set up that Portsmouth uses for deep water video is rented out at £100 per camera per day. So I know there is scope to do it cheaper, even if the unit costs £500...


  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #32 on: May 08, 2012, 10:43:54 AM
Here's a bit of a jumbled update.

The S100 is pretty sweet. IQ isn't bad at all. I'm impressed with the fully auto mode and it's focus tracking abilities. The manual options are a bit clunky, shooting RAW is fairly slow.

Full HD footage hits the 4gb limit within about 15-18minutes. 720p lasts 22min or so. A bit annoying, but I think ultimately this was the better choice than a  dedicated video camera as it'll get more use, the CHDK is in alpha at the moment, so in another month or so I should be able to add interval shooting and motion detection to the camera, which should be sweet. Also, work is looking into getting the Contour camera for a similar project that they've started to consult me on :D

Still waiting on the housing, which hopefully will arrive today. It's been a challenge getting one as my local shop sold out, and 3 different online shops that listed them as in stock actually had them on back order. Ended up getting a housing from Amazon.

As to the frame, I've got a sheet of Aluminium from the Tech school at Uni. I've drilled out 5.5mm diameter holes, and had to order some 1/4" 20 tpi bolts off of the internet as our metric 1/4" bolts are actually 25 threads per inch so don't fit camera threads.

I'm hoping to get some rope later this week, and test the housing in a water butt. Then this weekend will be deployment #2. I'll also try the camera with CrabCam MkI for some baited footage too.

Re: CrabCam
Reply #33 on: May 09, 2012, 00:09:44 AM

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #34 on: May 09, 2012, 08:43:15 AM
That's so cool.

I've also been looking at drones/helicopters for aerial stuff. Maybe this is just the start point for an ROV :D

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #35 on: May 12, 2012, 19:47:38 PM
Finally got down to Mudeford to test out the new camera and frame, but because of the sh*tty weather we've been having lately, and the low tide, it meant the water was the colour and consistency of tea that has been brewing for months.


I'd say it's getting there though. The next improvement is that I need to put some kind of spindle on the winch I made, to make the line reel in tightly. As it is the line goes all over the place on the handle causing one side of the frame to raise/lower faster than the other, making it quite jerky.


cc2 c by Chris_Moody, on Flickr

I've also established that it's going to be very tricky to do some video->photo panorama editing. I'm better off looking into getting the CHDK and getting interval shooting to work so I can stitch a Pano that way.

Re: CrabCam
Reply #36 on: May 12, 2012, 23:52:18 PM
The video clarity looks stunning above the water, really really good. Hopefully you'll get some steady waters soon  to test the underwater performance.
Formerly sexytw

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #37 on: May 13, 2012, 09:43:05 AM
I've managed to get the alpha CHDK running on the S100 and figured out how to use the intervalometer. I'm thinking around about 1 photo every 5 seconds, lowered slowly down should do. Possibly 3 seconds, to ensure that if one is no good there should be some overlap. Will also have to try with and without flash.

Yesterday I walked down to a local marina and got permission to go there later today and try it out. The water was still and looked maybe as clear as it did the first time I went to Mudeford. I'm hoping to try and get a lot of clear photos to do the species analysis, as well as use some bait to see what's lurking at the bottom of the marina. Stay tuned :D

One other problem is the camera gets quite hot when recording continuously, which is almost guaranteed to fog the housing up. It did this at mudeford after about an hour, though it was also in the sun slightly too long before the last film we did.

Re: CrabCam
Reply #38 on: May 13, 2012, 11:35:42 AM
How much room have you got in the case, have you thought of getting some silica gel to combat the moisture?

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #39 on: May 13, 2012, 20:57:09 PM
I've got an old pack of silica gel in there, but I think it's spent/fully used up. There's a bit of space for a few packs. I think the best thing to do is close the case up in a cold air conditioned room, and then keep it out of sunlight as best you can.

The yacht club marina I was at today was much better than Mudeford, though it's raised several fundamental issues with my plan to develop this as a means of rapid species assessment.


Current issues:

#1
The winch/rope winding needs sorting so that both sides lower at the same rate. I guess the best way to do this is to put some spindle things on to force the line to wind in a small area.

#2
A wider angle of view is needed. This is a problem though as any further away and visibility is severely restricted. I'll need to look in to ways to improve visibility. This will probably require the right conditions and doing it at night. This is kind of a major issue as all marina's are going to have the same kind of conditions due to their sheltered nature.

#3
Better control of the camera would be good. Potentially CrabCam MkIII. Some kind of telescopic pole with an adjustable ball head design on the end would be good. Would make raising and lowering in shallow water quite easy, and also I could try and make it so I can get to the areas not directly to the side of the walkways.

#4
Image quality
I used the CHDK interval mode to get some shots, but these were 90% very iffy. Could be just a case of trial and error to get the right settings, but one issue is writing buffer. I'm going to look into using VirtualDub to extract single "good" frames from video and then see if hugin can stitch the images together. Some of the images though are pretty good, especially as they were on a timer, they look like I'd framed them deliberately.

All in all I'm kind of feeling that a big wall is coming up fast if I can't get more of an area covered and stitched together.


CrabCam MkII Parkstone Bay by Chris_Moody, on Flickr


CrabCam MkII Parkstone Bay by Chris_Moody, on Flickr


CrabCam MkII Parkstone Bay by Chris_Moody, on Flickr


CrabCam MkII Parkstone Bay by Chris_Moody, on Flickr


CrabCam MkII Parkstone Bay by Chris_Moody, on Flickr
Last Edit: May 13, 2012, 21:34:34 PM by zpyder #187;

Re: CrabCam
Reply #40 on: May 13, 2012, 21:33:48 PM
For the winch why dont you just tie the four corners together, bring them together in a single line and attach it to some heavy duty fishing line.

Use a fishing spool on a modified rod to lower and raise the contraption.

Sent from my GT-I9000 using Tapatalk 2

  • Offline Eagle

  • Posts: 1,902
  • Hero Member
Re: CrabCam
Reply #41 on: May 13, 2012, 21:52:17 PM
Lol.  UK waters really are sh*te!  ;D

Good work though. :)

  • Offline zpyder

  • Posts: 6,946
  • Hero Member
Re: CrabCam
Reply #42 on: May 13, 2012, 22:34:10 PM
For the winch why dont you just tie the four corners together, bring them together in a single line and attach it to some heavy duty fishing line.

Use a fishing spool on a modified rod to lower and raise the contraption.

Sent from my GT-I9000 using Tapatalk 2

MkI was like that. Reason for the 2 lines is to prevent it from spinning around due to water currents, and allow me to move it around in the water.

Re: CrabCam
Reply #43 on: May 13, 2012, 23:37:42 PM
Ah, figured it had to be some reason you did it with two.

Okay so er... Are there dual fishing reels out there? It'd be perfect for your needs.

Sent from my GT-I9000 using Tapatalk 2

Re: CrabCam
Reply #44 on: May 14, 2012, 19:09:11 PM
I'd assume the issue here is the line being used?

Just using a fishing line with the same setup may solve your problem and stop the snagging?

Maybe use a couple of reel holders to keep them in line, and if the issue is just getting a constant lower rate, then attach it to a variable speed electric drill?

Nice quality vids and pics from the setup though, shame it's not quite wide enough for you?

Have you looked to see of there is a 3rd party wide angle adapter that will bolt on to the lens, assuming there is room in the case?

0 Members and 1 Guest are viewing this topic.