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I love these stately, grand events. Through time-lapses, I try to convey this, but it's never the same as being there in person. Doing them in 3-D with Luca Vanzella is also quite fun - one of our background projects is doing 3-D time-lapses.
A learning space
These pages are as much a place to post my efforts as they are about helping others - I've learned and benefited so much from others, pay it forward. There are of course professional tools out there at professional fees, but here I am concentrating on what is available for free, and deliberately not being exhaustive.
It's great when there is the Goldilocks situation of just enough earthly motions of clouds or reflections to make it more dynamic, but that makes the image processing all the tougher. On the other hand, would we do it if was easy? Deep down, we're suckers for a challenge.
It's most challenging when high dynamic range (HDR) is needed to capture both the bright Moon and a fainter foreground simultaneously. Our eyes handle this easily, but not the camera. The only way is to bracket one's exposures, say 1/2000s for the Moon and 1.6s for the city (12 stops!) and composite them afterwards. As Sir John Herschel pointed out, the Moon is as bright as a rock in full sunlight. These days I shoot almost exclusively with brackets and decide later how to process them.
Moonstroked: an all-night, single camera, high resolution, HDR panorama of Luna's lowest arc:
In daylight
15 minutes before sunset or after sunrise, the foreground is of similar brightness to the Moon, so you can get both with one exposure. With minutes to go before sunset, the light levels plummet. Sometimes you can get away with it :
but if you want the trees lit up, you must compensate.It's amazing how dark the foreground really is.
At night
For the image to reproduce how it looked to the eye, you have no choice but to make a composite: combine one image of the properly exposed Moon with one of the foreground when the Moon is out of the frame (either before or after, and it can be tricky sometimes). Photoshop or GIMP makes it easy by using "lighten"
Watch out for focal length and exposure! 3.2sec on 100mm (small sensor) shows slight trailing!
HDR - High Dynamic Range
The concept: Take differently exposed images and merge them into a single one capturing the faint detail and the information in the highlights:
Combine into:
Camera settings and enfuse settings for HDR images of the Moon: if you can, bracket across 5-7 exposures, and make sure you have a pretty dark frame ("underexposed") - I did not have success with 3 images in previous cases. Good news - it is possible to fake an underexposure after the fact, to a degree: Here's my trick
HDR the method: It is easy to go past an attempt to faithfully reproduce what the eye saw, beyond the surreal into, well, art. There is no truth, just interpretation and taste: at night when you wake up, your room is in shades of gray. A picture showing colors "feels wrong" yet you must accept that your eyes in fact are not telling you the truth about the color!
The following applies only to Windows users.
HDR by tone mapping. Patrick David has a good tutorial using (free) Luminance HDR. This is the technique that can be easily overdone.
HDR by masking. (free) GIMP with Exposure-Blend tutorial: digital version of astronomer David Malin's film unsharp-masking technique
HDR by Enfuse (free). EnfuseGUI is a nice interface that lets you play with the parameters. And it lets you batch process hundreds of bracketed image sets! Pixels are chosen from each image weighted according to qualities such as proper exposure, good contrast, and high saturation. For HDR panoramas, try Hugin . Here is a tutorial for enfusing only (no panorama).
HDR time-lapse
It's great to get a nice result for one triplet, but now we have 300 triplets in a time lapse to process! Even with saved settings, there are few people who have the patience to do this 300 times, and again for the next time lapse. Hang on! This is what computers are good at. One free option is a wrapper .bat script developed by Erik Krause. It's called a droplet because you drag and drop a group of image files or an entire folder onto the droplet icon. Another is EnfuseGUI which can also take an entire suite. Here's my enfuse-tutorial (Note Windows only). By itself it chose the correct number of frames in a bracket set, though you have control to change this. So for 600 quintuplets of 3400x2300 it took 4 hours, but I was away doing other things!
Lately I have used enfuse on the command line while in batch mode, because I can use the half-sine function instead of Gaussian. It gives me more control on eliminating the bleached out highlights from the enfusing of exposures.
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