What’s Your Preference?

Nobie · #1 (**permalink**) 01-04-2011, 03:26 AM

Sorry for the double post, can't find a delete button.

Quote:

I will be heading out for a long cabin trip where there is zero light pollution, also armed with a borrowed equatorial track mount for an attempt at some galaxy and nebula shots. Anyway, I've never dived this deep into astrophotography, other than long exposures to grab star trails or catch meteor showers. Any insight would be great.

My first question, obviously NOT using the track mount, is regarding the rule of 600. Does this rule care if you are shooting full frame or not? If I am shooting with my 50mm on my Nikon D200, is it 600 / 50 = 12 seconds? — OR — do I have to compensate for the cropped sensor and shift my mm to accommodate the "true" mm and make it 600 / 75 = 8 seconds?

Nobie · #2 (**permalink**) 01-04-2011, 01:36 PM

What the?!? The mods deleted the good one! ARGH! Sheesh, forget it.

IABoomer · #3 (**permalink**) 01-04-2011, 09:25 PM

Quote:

Originally Posted by http://www.luminous-landscape.com/tutorials/d60-night.shtml

The Rule of "600"

As discussed in detail in my article on meteor shower photography, the quickest way to determine the longest exposure that is possible for any given focal length lens, without the stars streaking, is to divide that focal length into 600. (This is the formula for 35mm. Larger formats are laxer, smaller formats more unforgiving). Since the 35mm focal length equivalent for the 14mm lens that I was using on the D60 is 22mm, I used a 30 second exposure (600/22=27 seconds. Close enough).

Of course if I was willing to accept the stars turning into trails I could have done a much longer exposure. But my goal was to experiment with trying to achieve a natural appearance that blends the best of daylight landscape photography with a "night look", with stars playing a dominant role.

Use the effective length.