A lunar eclipse time-lapse
A total lunar eclipse was visible from large parts of the world on 27-28 September 2015: a supermoon lunar eclipse, no less, since it occurred while the Moon was in the part of its elliptical orbit that takes it closest to Earth. Norbert Heinz, aka HomoFaciens, made a time-lapse film of the event using his Raspberry Pi and camera module together with a 100-300mm zoom lens.
Norbert’s narration takes you through how he prepared his set-up, which required a bit of modification to the camera board, and discusses its limitations. As we’ve come to expect with his projects, you can also watch a German-language version.
The video shows the eerie, inky shadow of Earth creeping across the face of the Moon, and towards the end of his recording, Norbert captured some very pleasing shots of a passenger jet crossing the field of view. He didn’t succeed in picking the correct combination of values for light sensitivity, aperature and exposure time to record the Moon’s surface in the Earth’s umbra, so the video doesn’t show the reddish glow of the blood moon (he intends to upgrade his kit before the next time he tries this, in 2018). However, f varas-genestier captured some lovely images of a 2014 lunar eclipse with his low-cost Pi + Pi camera build, so it certainly can be done. [Edited to add: François Varas tells us that these Moon photographs weren’t in fact taken during an eclipse. We’re sorry; we were led astray by the way they were referenced elsewhere on the web. They’re still lovely photos, though, François!]
Meanwhile, forum member “mntmst” had a completely different project for the lunar eclipse. They describe a very interesting experiment they undertook with their children to investigate changes in the moonlight during the eclipse, using a Raspberry Pi, seven solar panels, an ADC and an original Gertboard. The information and images they’ve shared, and their results, are well worth a look.
If you’d like to try out a lunar photography set-up similar to Norbert’s, you’ll find useful information in his project pages, available in both English and German. But if you’re new to the camera module, a good place to start is with the time-lapse set-up worksheet in our Resources section. These projects are a great way to achieve really appealing results with a simple set-up, and their variations are limited only by your imagination.
I am really happy and honored to be mentioned here. Really :), but the pictures are not specifically from the lunar eclipse, the post pre-dates the eclipse (posted on april 2014), and I would not like to take credit for something I didn’t do.
If by any chance the text on my blog or the images lead to think the pictures were from the eclipse, please accept my apologies, it’s not was I was looking for.
Oh, I’m sorry for the misunderstanding! I didn’t think they were from the recent eclipse, but I was under the impression that they were taken during one that occurred in April 2014; another site referred to your blog post in a way that made me think this was the case, but I should have been more careful to check. I’ve added a note in the post above. Thank you for commenting!
We need more of Norbert’s excellent videos, they are an absolute treat and well worth watching.
there is a metoer shower due this weekend i think, that might be a good use of the setup
depends on how long he can get the exposure etc to increase the light levels
You can very cheaply buy manual focus/aperture lenses on eBay and other sites. For instance, I just found a 75-300mm zoom for £9.99 delivered. Most are for obsolete film cameras but will work *really well* with a Pi camera, giving oodles of zoom and super image quality for very little money.
You will need to space the camera back from the lens as shown in the video but you don’t need anything posh. Anything you can hack and glue together will work fine. The important points are
– get the camera as square-on to the back of the lens as you can manage
– get the camera as close to the centre of the lens as you can
– to work out the spacer distance, open the lens aperture as fat as possible (smallest f/number) and point the lens at something fairly distant (the bottom of the garden or across the street will do) and set the lens focus to a little less than you measure or estimate the distance to be. Fire up the Pi and camera and move the camera back and forth at the back of the lens. You should find a point where you get a good focus, really zoomed-in image. Measure the distance between the back of the lens and the camera: that’s the distance you need to contrive with your hacked spacer. (If your spacer is too short, you won’t be able to focus on distant things like the moon. If it’s too long, you won’t be able to focus closer objects.
– some lenses have a tiny little lever at the back that used to interface with the camera mechanics to set the aperture. If you look through the lens and gently move the lever you’ll probably see the aperture (hole) get bigger and smaller. Unfortunately these usually go to their smallest aperture when you release the lever. The cure is to set the lens to its widest aperture and then glue the lever at its maximum-open setting. You won’t be able to use it on the original camera again but for a cheap, obsolete eBay bargain, who cares? JUST DON’T DO THIS WITH A LENS YOU PLAN TO USE ON THE ORIGINAL CAMERA!
Just my thoughts. Happy Making.
Another pi based telescope featured in the blog last year has entered crowd funding as well.
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