Potential Pinhole Analemma

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SJohnson
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Potential Pinhole Analemma

Post by SJohnson »

Hello all!

I'm thinking of starting a project on the winter solstice. I'd like to try to make a picture of an analemma using a pinhole camera (I'll probably purchase some from solarcan). I have a south facing side of my house that has a window I can easily use to mount the camera(s) outside for the roughly weekly exposure. I would do a 1 - 2 minute exposure once a week or so to give me some time around rainy days. I also think an all day exposure on the winter and summer solstice would be good to trace the solar path and give some more time for foreground exposure on the paper. I'll set my reminders in UTC so Daylight Saving Time doesn't ruin the project (at least I can try to control one thing that might ruin it :D ). This may be a wild goose chase, but could produce a neat image after a year.

Has anyone tried this with a pinhole solarcan style camera?
Should I tilt the can to match my latitude, the earth's axial tilt, or higher to capture the higher summer solar position's (I know in the past solargraphs I've done the summer will get cut off at the top)?
Any other considerations I should think about over the next month?

Thanks!
Shawn


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Montana
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Re: Potential Pinhole Analemma

Post by Montana »

Shawn, we have lots of discussions and a video you can watch here which might be helpful, The Solarcan will return next month as the imaging challenge
viewtopic.php?t=35964

A pin hole camera is like a camera obscura, the higher you place the hole on the can the more you will get the higher altitude Sun. If the tops were cut off you need to raise the pin hole higher as the image is inverted.

For an analemma you will need to expose the camera at exactly the same time each week to get a spot (will need the Sun to shine too at that time). I hope this helps

Alexandra


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Re: Potential Pinhole Analemma

Post by nicspenceryork »

Hi Shawn,
By coincidence, I'm going to attempt to record an analemma from solstice too. I'm going with a square or rectangular tin rather than a cylinder as the cylinder produces a quirky curve to the image. I think both approaches will be interesting and we can compare the results next year!
Good luck with it,
Nic


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Re: Potential Pinhole Analemma

Post by Montana »

Are you trying the Solarcan Puck Nic?

Alexandra


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Re: Potential Pinhole Analemma

Post by nicspenceryork »

Well... the Puck is my new favourite camera for holiday/event captures so I want to keep it free for adventures!
I'm going to make a pinhole camera for this analemma project. I cut out the pinholes from used solarcans (only if it got crushed... and if it didn't crush, I use the whole can again) and attach them to other tins. I reuse the Solarcan pinholes because they're precise. I have made too small a hole before and not let enough light in and too large a hole which gives a blurred image! I use a piece of Ilford Photographic Paper MGRC Multigrade RC Delux Glossy 5x7" (I cut them down to size depending on the tin in dark, in the glow of a red headtorch!). I bought a pack of 25 pieces and have tried lots of things with homemade pinhole cameras in different places and with different numbers of holes. The opportunites are endless!
Nic


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Re: Potential Pinhole Analemma

Post by SJohnson »

Thanks for the details Alexandra and Nic! The video doesn't want to load on my PC so I'll try the Mac later today.

That's great that we had the same idea Nic! I would love to compare the end results. I didn't consider the curve of the can in thinking this through so no matter what comes out it should be interesting.


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