Showing posts from June, 2010

Analysis of Fader ND (mark I) filter image quality

In February 2010, I purchased an 82mm Fader ND Filter (ND2 to ND400) from the official eBay store for Light Craft Workshop .  The label on the filter reads "82mm  Fader ND [W]  HL-OPTICS". The purpose of a Neutral Density (ND) filter is to reduce the amount of light, therefore allowing for slower shutter speeds.  A variable ND filter allows you to vary the amount of light by rotating the front of the filter. When shooting video, the shutter speed is normally fixed - it is tied to the frame rate giving the required Shutter Angle (e.g. 180 degrees) controlling motion blur.  When shooting video, the only way to prevent over exposure in bright light is to Stop Down the aperture.  This limits your ability to use the aperture to control depth of field. A variable ND filter is particularly useful for video, since it allows you to control exposure independently of the aperture and ISO.  Specifically you set your fixed shutter speed, choose your depth of field, then set expo

More chickens

We've now got five chickens, having purchased another two today. This is our family of hens. "Beatrice" is a Silver Laced Wyandotte , purchased 13th June 2010. "Snowball" is a White Wyandotte Bantam , purchased 13th June 2010. "Dotty" is a Cuckoo Pekin Bantam , purchased 1st November 2009. Sadly she had to be put-down on 7th March 2011 after developing paralysis from a virus. "Edna" is an Isa Brown , purchased 1st November 2009. "Dora" is an Australorp , purchased 1st November 2009. Click here to view more photos of our hens.

New chicken coop

Recently I wrote about how I had designed an automatic door opener for our chicken coop by modifying an alarm clock.  Refer to this post ( Building an automatic chicken door opener ) for more details of the design. The automatic door opener has been installed into the new chicken coop, here's a video of it in action. Our three hens come out in the order Dora first, then Dotty the bantam and then finally Edna pushes past. The new chicken coop is much larger than the old one. Note the chicken coop is a one-off, home-made design purchased off eBay, which we've then modified to suit our needs. There's plenty of space in the nesting boxes for our hens .  In fact it's probably too big now, so we'll definitely have to get some more girls. Plus the most important thing, I've converted my automatic door opener to suit.  Now it operates vertically, and hence why the clock is on a 90 degree angle. The operating mechanism is much less prone to error.  Specifica

Resolving FOSCAM connection dropouts

I bought a FOSCAM FI8908W wireless IP webcam off eBay recently. It has lots of features for the price. However, I've had problems with being unable to connect to the camera after a period of time (an hour or so). Power cycling the camera would fix the problem. I've tried upgrading to the latest firmware (version is supposed to fix WiFi disconnection problems), but it did not fix my problem. Problem analysis The problem is not related to my browser or the wireless network. I've tried disabling DHCP (router based static IP). It turns out the problem is that the webcam simply ceases to respond to ARP  (Address Resolution Protocol) requests (once in this broken state). ARP is a mechanism to translate between IP addresses and device MAC addresses. It underpins all IP communications over both Ethernet and WiFi, since at the lowest level it relies on exchange of packets between device MAC addresses. The ARP protocol allows a network device to discover t