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Italian Festival Some evening neighborhood fun -
Moon Waxing Crescent Some good moon views in January -
Social Media Week 2013 I was early...
Mildly Interesting Things
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iPad Slow Charging
Written by John SpadeTIP: Slow iPad Charge? A Simple Fix with Cable Upgrade can Charge your iPad or iPhone 30% Faster
UPDATE: The same is true for new iPad, iPad 2, iPhone 4S
Some people have noticed that the iPad will not charge or seems to take forever to charge on some after market cables, especially if they are longer than the standard charge and sync cable. In fact I have seen this on standard length cables where the iPad battery drops even though I have it plugged into the
charger it came with and it says charging.The main reason for this is pretty simple. USB charges around 5 volts and if you are expecting the over 1 amp ( 5 watts ) on the standard cable, it better not be very long. This is because the size / gauge / AWG / diameter of the wires is too small. By specifications, USB 2.0 cables can have wires with AWG as high ( small ) as 28. The result of this is that during the high speed charge phase ( usually the first 50% ) you are potentially losing 30% charge efficiency with the stock cable based on my multimeter tests. Not very green and very annoying that Apple cheaped out by a few pennies on this.
First a table of solid core wire AWG for power transmission ( most USB cables have stranded wire for more flexible cables ). The following is a table that shows common iPhone or iPad charging methods, for nerds the values are approximate and designed to carry the 'concept' and length is length of cable but AWG for true 'round trip'. Smaller AWG means a thicker wire. Data from Powerstream calculator.
Charger Current/Power 3ft AWG 6ft AWG 10ft AWG Approx Voltage Drop PC USB 0.5A/2.5Watts 28 26 24 0.4 iPhone 3GS 1.0A/5.0Watts 26 24 22 0.5 iPad 2.1A/ 10Watts 22 20 18 0.5 Written on Wednesday, 06 March 2013 14:54 in Technology Be the first to comment! Read 191 times Read more... -
Glass Filters and Digital Cameras
Written by John Spade
Glass Filters and Digital Cameras
There are a host of techniques such as HDR or tone mapping to improve the display of your images on computer monitors and in some cases on prints. Something that is often overlooked is the use of glass filters. For a long time I used a polarizing filter ( CPL type ) to cut reflections and help improve some of my images. I don't always want the reflections cut, however, such as in the attached/linked photo.
Color filters are an obvious choice in BW photography, but in color photography you don't want to skew the color too much; or so I thought. I realized that I preferred amber colored lenses on my sunglasses here in Florida because of all the blue light. I decided to try similar filters for my digital camera. In this case a B+W 77mm 'Skylight' 1A filter for my Canon 60D with 17-55mm USM IS and 10-22mm.
The results were very exciting and make me want to try more aggressive filters for color photography. By cutting some of the blue light ( dominant ), I can capture more of the light I want with out blowing out (over-exposing) areas of the photo. I can expose longer, pulling more shadows or elusive colors.
I will say the multi-coated filters help a lot during the day, or any time shooting into light sources. It helps reduce lens flare and I believe it improves contrast a bit too.
Written on Saturday, 23 February 2013 14:27 in Photography Be the first to comment! Read 201 times
