ShutterSnitch, Eye-Fi, and MyWi

Rob Galbraith wrote an excellent article regarding iPad tethering. Tethering allows me to use a much larger and more color accurate screen to review my images. The LCDs on the back of cameras are wonderful, but it is hard to analyze your photographs on such a small screen. Using an iPad (or iPhone/iPod touch) to get around this limitation has proved to be amazing on photoshoots. It has become an integral part of my equipment that I bring to each shoot.

Having the photos on my iPhone has also proven to be very useful when talking to prospective models, giving art directors greater input during a shoot, asking property owners for permission to use their building/land for a photoshoot, etc.

The basic premise revolves around 4 parts:

• ShutterSnitch: This program runs on any Apple iOS device (iPad, iPhone, iPod touch). It receives photos from your wireless transmitter and displays the photo within a few seconds. On average, it takes about 4 seconds to transmit a photo to my iPhone.
  
• Wireless transmitter: An Eye-Fi card or dedicated wireless transmitter. The Eye-Fi card syncs well with ShutterSnitch, but it may or may not play well with your camera. Check this page on Rob Galbraith's review to see what is recommended for your camera. Canon and Nikon also make wireless transmitters which offer more versatility and throughput, but are significantly more expensive.
  
• Wi-Fi network: Due to shooting on location, I require a wireless router. There are many battery powered options, but I have chosen to go with a program called MyWi. Unfortunately, this program is not on the App Store, but it is on Cydia. If you wish to use this program, you will have to jailbreak your iOS device. It allows me to create an ad-hoc WiFi hotspot, and also enables USB tethering.
• Display: Any iOS device. An iPad is the ideal solution, but an iPhone or iPod touch will work as well. I currently use an iPhone, but have been lusting after an iPad to analyze my photos on a much larger screen.

This combination has been fantastic for me. I was initially worried about the iPhone's battery life, but after using it in 30-35 degree weather for 3 hours, the battery life only dropped 40%. If you happen to use MyWi, and leave it on constantly during the shoot, make sure to change the transmit power to the lowest setting (30%). At the highest setting (80%), it does go through your battery life at a much faster rate.

Below are two screenshots of ShutterSnitch in action. The first photo shows image preview, while the second shows the UI with three photos that I have selected.

Ashley

Had a blast doing a quick photoshoot with Ashley in an old abandoned building. Ashley performed admirably in the 30-35 degree weather. Wonderful location (thanks to Eric Ashley), but it's too cold to try more advanced poses. Hopefully we'll be able to go back when the weather is more favorable.

Canon 70-200 f2.8L IS Mark I vs Mark II

I recently purchased the Canon 70-200 f2.8L IS Mark II and wanted to compare it against my Mark I. I have a 4 x 8 uncut sheet of $2 bills that I use for lens tests as it generally has more detail than my camera can currently resolve. Click on the photo to enlarge ~5.4 MB.



Notes:

• I was using the PocketWizard's PowerTracking/eTTL feature to automatically compensate for the change in aperature on my 580EX II flashes. The combination worked for the most part, but there are slight fluctuations in brightness throughout the test.
• The Mark II is noticeably sharper for large aperatures
• The Edge 70mm Mark II crop is less sharp than the Mark I counterpart. After looking at the other corners (not pictured), the Mark II wins on 2 of them, and 1 is roughly a wash.
  

George & Melissa

An engagement shoot with George & Melissa. Big thanks to Eric Ashley for playing assistant extraordinaire.

HyperSync

Before getting started, I ran across this well done video talking about Shutter/Flash Synchronization. I highly recommend watching it before going further into the article.



The three main factors that affect HyperSync are shown and tested independently:

• Shutter speed
• HyperSync Offset
• Flash Duration / Flash Power

Shutter Speed

The very obvious effect of going over your x-sync speed. I'm currently using a Canon 1DS Mark II and have an x-sync speed of 1/250.

The images are very boring horizontally, so I combined photos with varying shutter speeds. The numbers across the top are my shutter speed.

Canon 1DS II @ ISO 100, f 2.8
580EX II @ 1/128 power



The black band at the bottom of the screen is caused by the second curtain closing before the flash fires.

HyperSync Offset

RobGalbraith's HyperSync writeup (pg. 2 on) will do a much better explanation that I will.

HyperSync Offset can be adjusted from 0 to -2500. The more negative the number, the sooner the flash will fire. Unfortunately I didn't test -2000, -2250 and -2500, but you should know what to expect.

Canon 1DS II, ISO 100, f 2.8
580EX II @ 1/128 power

Click the photo to see the animated gif.



I'm a little unsure why the HyperSync offset of 0 is producing a slightly darker image. I will have to investigate this later.

Flash Power / Flash Duration

The graph below shows the intensity vs time for a full power flash.



Most speedlights squelch a full power flash for dramatically improved flash durations.

Canon 1Ds II @ ISO 100, 1/1000
580EX II



The full power flash duration is much longer than exposure duration. To make the most of this, I've found out that I can shoot 1/640th at 1/1. I hope to follow this a little bit more in depth by comparing High Speed Sync (HSS) with 1/1 shots in a later post.

It's also interesting to note that 1/8 to 1/128 are roughly the same duration.

PocketWizard MultiMax vs Flex TT5 feature set comparison

MultiMax

• Long Range Mode for remote camera triggering: Limited to 1/125 sync speed.
• Short Range Mode for working at extremely close distances
• Custom ID & moving your Custom ID frequency
• Noise Sniffer: Senses fast, slow and peak.
• Radio Relay Mode: Delay of ~1/800 seconds per relay.
• Trigger confirmation and flash confirmation (with optional cable)
• Quad triggering: 4 zones per channel and the ability to receive in multiple zones
• SpeedCycler
• Fast Mode: syncs up to 1/1000th
• Intervalometer/Multipop: Doubles as Self-Timer or Cable Release
• Programmed Rear Curtain delay

Mini TT1 / Flex TT5

• Improved Rear Curtain sync: Doesn't need to be programmed like the MultiMAX and fires precisely at the end of the shot - unlike Canon's implementation
• Pre-Flash Boost Mode: For using E-TTL in bright conditions where the normal pre-flash is not bright enough for the camera to see
• DoF preview: Pseudo-modeling lights
• Higher Efficiency High Speed Sync (for shots above your X-sync): Huge gains in efficiency due to much tighter timing, between 0.5 and 1.8 stops brighter output
• HyperSync: Achieve better than X-sync with many cameras and flashes. Gains between 1/3rd and 2/3rd stop better sync speeds. Fast and smaller shutters have the most to gain.
  
• AC3 Zone Controller / ControlTL: Wirelessly control the power between 3 groups of flashes, whether they're in E-TTL or manual.
  
• Adjustable antenna

The bold lines denote the features that I am most excited about from each transceiver.

580EX II + CP-E4 recycle times

I'm hoping to update my blog occasionally to consolidate various tidbits of information I have learned about photography into one location.

How fast can your 580EX II recycle a full power (1/1) shot?

• Alkaline batteries: ~3.6 seconds
• Sanyo Eneloop batteries (2000mAH NiMH): ~2.8 seconds
• Sanyo Eneloop batteries + CP-E4: ~1.0 seconds

The CP-E4 recharges your flash at a fast enough rate that you should be aware of the heat buildup in your flash head.