Beer can solargraphy

[HatHair]

Hello. This is my first post in the group. I'm wondering if anyone knows what caused the 4, dark, vertical lines seen in the attached photo. The photo is a 6-month long image on a 5x7 sheet of photo paper. The paper was in an empty beer can, the inside spray painted black. I don't know the size of the pinhole, but it was made with a small safety pin. The metal burs were sanded off. I've seen this in a couple of different cans. The black lines seem roughly harmonic, which makes me think it is some kind of light diffraction effect. Note that the image can be seen through the dark lines.

Also, I held the paper in place with paper clips. I don't think these are responsible as I've seen this effect in photos not held with paper clips.

I've surfed the web, no luck.

Thanks.

 

[Sirius Glass]

Hello. This is my first post in the group. I'm wondering if anyone knows what caused the 4, dark, vertical lines seen in the attached photo. The photo is a 6-month long image on a 5x7 sheet of photo paper. The paper was in an empty beer can, the inside spray painted black. I don't know the size of the pinhole, but it was made with a small safety pin. The metal burs were sanded off. I've seen this in a couple of different cans. The black lines seem roughly harmonic, which makes me think it is some kind of light diffraction effect. Note that the image can be seen through the dark lines.

Also, I held the paper in place with paper clips. I don't think these are responsible as I've seen this effect in photos not held with paper clips.

I've surfed the web, no luck.

Thanks.

Welcome to APUG Photrio!!​

 

[koraks]

Welcome to Photrio, @HatHair!
I'd say your lines probably have to do with reflections from the semi-shiny internals of the beer can, and/or possibly the paper itself.

Or a very patient Easer bunny eager to have its portrait taken.

 

[Donald Qualls]

Welcome to Photrio, @HatHair!
I'd say your lines probably have to do with reflections from the semi-shiny internals of the beer can, and/or possibly the paper itself.

Or a very patient Easer bunny eager to have its portrait taken.

I'd expect internal reflections/focusing to produce lighter areas, not darker (given that this scan appears to have been inverted to a positive). Light wave interference wouldn't darken all colors in the same place. Given this was a six month exposure, it's very tempting to suggest that grass (or similar) grew up in front of the can during the exposure (and moved some with breezes, hence being somewhat transparent) -- and then was gone by the time you took the can down to view/scan the lumen print.

 

[koraks]

I'd expect internal reflections/focusing to produce lighter areas, not darker

Yup, that bugged me as well.

But I think the grass-hypothesis is problematic in that it's an awfully static image that moreover features the kind of surface qualities I'd expect of RC paper, hence I still think it's some kind of reflection artifact.

I'd like to see a photograph the original image (negative?)

 

[gone]

I think it would be virtually impossible to figure out what went wrong w/ a film that's inside a beer can w/ a hole in it and left for 6 months unattended. Even Sherlock Holmes couldn't figure that out. Anything may have happened, and you would not have been around to see it, so who knows? I'd like to try something like this some time, but getting the film in and out of a bottle of Bourbon may be too challenging. Beats drinking beer though.

I say go w/ it, it's an interesting image.

 

[HatHair]

Thanks for replies/thoughts. As a follow-up, I've attached an image of the scanned paper, before inversion and adjustments. Also, the can was on a second story downspout and viewed daily. Too high for any roll by transient vegetation.

Maybe I'll try a better brand of beer.

 

[DWThomas]

Strictly in the wild guess category --- the image being upside down in the can, could it be condensation (or other undesired moisture) ran down the surface in a couple of spots? I've no idea what that might do.

 

[koraks]

an image of the scanned paper

I see very clear reflections on the paper surface. Are the same image defects present in the actual paper if you hold it in your hand? I.e. it's not an artifact due to lighting while scanning...?

 

[Donald Qualls]

an artifact due to lighting while scanning

I hadn't considered that possibility, but if the paper has a set-in curve (as it well might after six months in a beer can on the downspout) that might well account for the light areas on the negative.

 

[NedL]

I suspect that Dave guessed right. Remember the paper was upside down from the way it is shown here. I think there was moisture from condensation that migrated "down" from the bottom of the paper, which probably got wet. Wet areas on solargraphs often appear lighter on the paper ( darker on the inverted scan.)
Have fun!

 

[HatHair]

Thanks for the replies/suggestions. Also, the lines are visible on the unscanned paper, so not a scanning artifact.

 

[MattKing]

I wonder if your beercan could have a light leak, leading to bands of printed out solarization.

 

[koraks]

printed out solarization.

I think you're definitely onto something here!

 

[HatHair]

I don't think there could be a light leak as the entire can is wrapped in duct tape. Only the top of the can was removed and replaced with several layers of duct tape and cardboard. Also, the image is visible through the dark bands.

 

[Donald Qualls]

Further, the bands are light on the negative, rather than dark. I don't think true solarization is possible with a printed-out image.

I'm still thinking something obscuring part of the view for a fraction of the exposure time (a few weeks, maybe?) is the most likely explanation. Too high for grass isn't too high for spider webs (close to the pinhole, they'd be huge and fuzzier than the sky/tree silhouettes) or similar, or something that blew onto the front of the can and then blew off again.

 

[HatHair]

Further, the bands are light on the negative, rather than dark. I don't think true solarization is possible with a printed-out image.

I'm still thinking something obscuring part of the view for a fraction of the exposure time (a few weeks, maybe?) is the most likely explanation. Too high for grass isn't too high for spider webs (close to the pinhole, they'd be huge and fuzzier than the sky/tree silhouettes) or similar, or something that blew onto the front of the can and then blew off again.

Thanks for your time/thoughts.

 

[Synthon]

Hello HatHair, are you still around?
I am now getting deeper and deeper into solargraphy and just stumbled over this forum while i was looking for Arduino based Shutter testing
I don't think the bands are caused by something obscuring the view, it's more likely caused by moisture.
I had similar bands in some solargraphs, the attached image is a solargraph made by a friend from a rooftop.