Solar grapahy and Lunargraphy

[VReijs]

Hello all of you,

I hope you know the idea of solargraphy , where a pinhole camera is put outside and it records the path of the sun over say 3 months. Below is one picture South_Sun that gives the Sun's path over a few months. Photographic paper was used.
I would also like to do this for the Moon's path (lunargraphy). What I did is that I covered up the pinhole during the day and only 'opened' the camera when a Moon would be visible (some 14 nights).
You can see in the other picture (South_Moon) that nothing is to be seen, while I am sure the Moon was there)...

So the question is, is the paper sensitive enough to expose properly? The Sun is well visible on the paper and say the paper is around ISO 10 to 25. The Sun would expose one particular point on the paper for around 2.5 minutes (due to its width of 0.5 degrees and its movement). The Moon is some 400,000 less in brightness (18.4 diaphragm steps). So what paper sensitivity is needed to get a similar picture for the Moon (or should I use film with what ISO?).

Any ideas are welcome.

Thanks.

All the best,


Victor

[VReijs]

Here is the link to this project I take part: solargraphy<dot>com

[jnanian]

hi victor

unless you has some sort of lens that focused the moon on the paper, i think the brightness of the moon
might have just "fogged" the paper.
perhaps if you rig a secondary glass / meniscus lens on your pinhole camera that can slide into position
as the pinhole slides out of the way, you will be able to get an image of the moon as you expected. they suggest the "perfect"
exposure of the moon to be "sunny 16 " ( full moon ) so it will be a short exposure ..

great images you posted ... i am a big fan of long exposed paper !

john

[Lee L]

It appears to be possible, but I don't have the answer personally. See this photo: http://ericrennerphoto.com/artwork/1..._negative.html

There is a contact link for the photographer, Eric Renner, a leading pinhole expert, on the web page, and he'd probably be able to help you with details on the pinhole and paper setup, although the image is 37 years old.

Lee

[VReijs]

Thanks Lee, will see if the authors wants to reveal his secret! THANKS!

[jnanian]

lee,

what victor wants to do is different than what eric renner did.
eric renner made a 7 pinhole camera and used it to make a relatively short exposure.
then processed the paper. what victor wants to do is leave his pinhole open for such an extended period of fime
that the image of the moon "stains" the paper and creates a solar(lunar)graph. the paper isn't developed ( or it will turn black )
and it can't be fixed ( or it turns white ) ... it is ephemera ... and it has to be skanned, or rephotographed or xeroxed ...


good luck !
john

[jnanian]

hi victor

i misunderstood what you said you did, or want to do ..
i thought you were making solar graphs, and for some reason
you just "opened up" your pinhole camera to expose the paper to the moon ? ...
as you could tell from my initial response, it didn't make much sense to me ...
i didn't realize you wanted to do the same thing you were doing with the sun, but ... with the moon ...

you might consider doing a "dry run" with an actual camera with a lens to make a shorter than 3month exposure of the moon.
i use box cameras when i do this sort of photography, i don't usually expose the paper for longer than a few hours ( a half - day was my maximum )
and i usually do it during the daytime, so i have full uv + blue light to work with.
i attached one of the last ones i did, its 3 sheets of 5x7 paper taped together
in a home made 15x5 box camera.

i don't think you will have much trouble though, if you plan where you put your camera
and use a really wide pinhole-aperture to make sure you get the rise of the moon when it is different ...
seeing rise and set position of the moon changes depending on its phases and the season

these might help you determine where you could set up your camera / pinhole camera
one gives an idea of where in the sky the moon rises + sets, the other is a planetarium sky-chart .

http://curious.astro.cornell.edu/que...php?number=642
http://stellarium.org/

good luck !
john

[VReijs]

Hello John,

Just to explain further. Indeed the Solargraphy project uses undeveloped photographic paper (and scanning this paper). I did not know that it can't be developed!!! And I just wanted to do now Lunargraphy, by using the same method as with the Sun (so scanned exposed photographic paper) but that does not work with the Moon (as I showed). So perhaps I thought naively that developing the paper might bring forward the moon light.
If paper is not sensitively enough, I could use the method of Renner (I think he uses film, instead of photographic paper and develops it later). But as you say I want to see the Moon's path over several days say a month (this will need covering up the pinhole during twi and daylight, which is a pity as it makes it more difficult in remote paces with out electricity, so loosing the charm of 'Salorgraphy').

So I don't mind the method of film, paper, scanning, developing; I want to record the Moon's light over multiple days (and the point of unmanned location comes later)...

Hope this explains my endeavour.

All the best,


Victor

[VReijs]

Hello John,

I have no problem finding the Moon (for direction of the camera). I did some projects for recording the moon rise and set at neolithic sites like Callanish using webcameras (so quite technology depending: www<dot>iol<dot>ie/~geniet/callanish/ ).
I liked the idea of Solargraphy of unmanned, no power needed, weather proof simple equipment in remote places.

It is just the idea of how to get it on film or paper over several days (preferable a month).
I know almost that I need to cover up the pinhole during twi/daytime. Someone was proposing to use the UV sensitive eye glasses, but I think these are not able to block the 400,000 stronger Sun. I don't think these can block the Sun during daytime to at least 0.00025%...

Thanks for all the advice!

All the best,


Victor

[jnanian]

hi again victor ...

yeah, i too like chemical free photography. it works very well and it is a lot of fun. i have wanted to make solar graphs, but we have too many trees near me, and i wouldn't get a good view of the horizon .. so i have settled on normal lenses box cameras and shorter exposures. same idea, but takes less time

i didn't realize you were doing your project in remote areas ...
have you thought of a solar power or dry cell powered "shutter"
using a timer? you can hook up a dry-cell battery to the timer and then have a "shutter" attached to that ... some large format cameras have electric shutters. it won't be technology free, but you could hook up a dry cell ( or solar cell ) to one of these set to "BULB" mounted to your pinhole camera ...

this stuff won't be technology free, but it might help ...

good luck !

john