This time is a kind of the sequel from the last post. I always take my smart-phone to back county. Not for phone calls obviously, because it is handy when I use LEE – Big Stopper filter. Big Stopper is 10 stop neutral density filter. 3 or 4 steps are commonly used to slow down shutter speed. But it is 10 stops; you can achieve minutes of exposure time! Here is the easy calculation for exposure time.
- 10 stops is the tenth power of 2 = 1024.
- So “Exposure time (sec) without Big Stopper” x 1024 = Exposure time with Big stopper.
For example, You have 1/125 of shutter speed before setting up Big Stopper, the final one will be (1/125)x1024=8.192 (sec). When you have 2 sec of shutter speed initially, you will have 2(sec) x 1024=2048(sec), 2048(sec)/60=34.13(min). Savvy! Now I set a timer and read an eBook. That is why I need a smart-phone all the time for the calculation, timer and eBook. One tip is, when you shoot with auto-exposure and Big Stopper is attached to a lens, you may need to compensate exposure to +1.5 to 2.0.
This photo was posted in my last blog post. The Bow lake in Alberta looks really calm in this picture. But in reality, the day was pretty windy and it looked like the picture below. The 45 sec of exposure totally calmed waves on the lake. Big Stopper adds a tinge of cyan; this may be problematic for some photographers. But I like the cool tone, which often adds ethereal feel to the image.
Here is other examples, shutter speed 30 sec and the bottom one is 3 min.
Lastly, I should be honest and share my inspiration of the long exposure. Please check out amazing, Michael Levin. Since I saw his works 2 years ago, they have been big influence on my images.