![]() astronomers watch for a condition called "seeing" and try to avoid taking astro-images on nights with poor seeing. When you then zoom-in (using a very long focal length lens) and/or crop in tight, it creates the illusion that moon is huge. without changing the apparent size of the moon. That means you can change the apparent size of the foreground subject by moving away to make it smaller. But since your foreground subjects here on Earth are MUCH MUCH closer, changing your distance to those foreground objects WILL change their apparent size. The moon is so far, that you're getting nearer or farther has pretty much no measurable impact on the angluar size of the moon. In reality, the moon is only 1/2 degree (angularly) from edge to edge (it varies a tiny amount during the lunar month but it's always extremely close to 1/2 degree). This makes the moon appear large in comparison to the foreground subject. features on Earth in the foreground with the moon above) you can exaggerate the apparant size of the moon by using a _very_ long focal length and then positioning your self quite a bit farther back from the foreground subject. If you're taking a photo that provides some foreground interest (e.g. This way you can see detail on the lunar surface. You want the moon to appear 'gray' - not white. in which case you'll need to increase the exposure. The moon will appear dimmer (and often yellow or orange). ![]() If the moon is low in the sky (near the horizon) the light has to travel through a lot more atmosphere. Use this "Loony 11" rule as your "starting point" but recongnize you may need to adjust the exposure - but it will probably be a pretty good starting exposure. They call this the "Loony 11" rule (which is also a catchy easy-to-remember name for the rule.) At f/11 you can set the shutter speed to the "inverse" of your ISO setting. ![]() This means a technically correct exposure would leave the moon looking pretty dark (because it actually is pretty dark.) One full stop down from f/16 is f/11 and this compensates rather nicely. While the moon is in full sun and you'd think you could use the Sunny 16 rule, but the moon has low "albeido" - meaning it's actually darker and less reflective than you might think. in this case you could increase the shutter speed by two full stops and shoot at 1/400th. which is two full stops open from f/16 - but then compensate by changing something else. it rolls off the tongue, and (b) only at f/16 is the shutter speed always the inverse of the ISO setting. at ISO 100 you can use 1/100th second exposure at f/16.īut the rule is a "baseline" and they choose that rule because (a) the name is easy to remember. That rule says that when something is in full mid-day sun, you can set the f-stop to f/16, then set the shutter speed to the INVERSE of the ISO speed. Normally the rule for outdoor sunlight is to use the "Sunny 16" rule. sometimes called the "Loony Eleven" rule. It turns out, the moon is in "sunlight" - that's why it's illuminated. ![]()
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