SHOOTING THE MOON

(Compiled by Grant Bilbrough)

Can use either a telephoto lens or a telescope.
Size of the moon on the negative depends on the focal length of the lens.

IMAGE SIZE(mm)=FOCAL LENGTH(mm)/110  (for 35mm film)

(Keep in mind that the largest practical enlargement from a negative is about 15X.)

Eg.  50 mm lens gives:			Eg.  900 mm telescope gives:
	IMAGE SIZE=50/110			  IMAGE SIZE=900/110
	IMAGE SIZE=0.45 mm			IMAGE SIZE=8.2 mm
	(on negative)								     (on negative)
	0.45 mm*15=6.8 mm			  8.2 mm*15=12.3 cm
	   (size of moon on print)						     (size of moon on print)

DETERMINING EXPOSURE:(approx)

note: this equation to calculate exposure times is good for any photograph.(with appropriate brightness values)

	BRIGHTNESS VALUES:

		10 = thin crescent

		20 = wide crescent

		40 = half moon

		80 = gibbous

		200 = full moon

Eg.  Full moon with T Max 400 and f/16:
Time (s)=162/(400*200)

      =256/80000
								=0.0032 s --->1/312.5 s    --->choose 1/250 s

LONGEST PRACTICAL EXPOSURE	 EXPmax (s) = 250/focal length
	Eg.  50 mm lens									Eg.  900 mm telescope
		EXP=250/50							 		 EXP=250/900
	                =5 s									   	          = 0.28 s --->1/4 s	

anything longer than these times will result in a blurred image due to the Earth's rotation. To achieve greater exposure times hand tracking is possible.

GENERAL TIPS:

• to get good shots of the moons rough surface (craters etc.) shoot the moon when it is not full. i.e. slightly gibbous down to a crescent moon.
• look to include other objects i.e. Jupiter, Venus, trees
• always(!!!) use a tripod.
• set lens to f/5.6 or f/8 for best lens performance.

most of this stuff was taken from: ASTROPHOTOGRAPHY FOR THE AMATEUR by Michael Covington

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