Solargraphy Baseline Exposure Time

Tried posting this in the Alternative forum on here but didn't get any responses yet. Was wondering if anyone in this forum could help me out with a question I have. Here goes:

Hello All,

Tried to figure this out before posting but couldn't seem to find anything. I recently came across some solargraphy image and really want to give it a shot. I was simply wondering, what is the shortest exposure time to get an image on the photo paper without developing? While doing my looking around, I've seen the famous 6 month shots but I've also seen one's that have only taken a day. That's quite a large range. I realize that the exposure time will have a lot to do with pinhole diameter. However, I'm sure .25mm - .50mm difference between pinholes sizes wouldn't make THAT much of a difference in exposure times. I'm sure there has to be some kind of baseline exposure time to get a visible image on the paper? Does photo paper not "overexpose" without developer? Any help would be great, thanks.

I just want to say: thinking about "exposure times" is just simply too ridiculous when it comes to solargraphy. You just make a decent pinhole. You set the cam in place. let it Expose for however long you like it. The end.

Yes, you can expose just one day and get something:

http://www.flickr.com/photos/rawhead/4125543313/

rawhead said:

I just want to say: thinking about "exposure times" is just simply too ridiculous when it comes to solargraphy. You just make a decent pinhole. You set the cam in place. let it Expose for however long you like it. The end.

Yes, you can expose just one day and get something:

http://www.flickr.com/photos/rawhead/4125543313/

Click to expand...

Thank you so much for the reply and opinion! Doesn't seem like too many people have much to say about the subject. I set a film canister pinhole camera out a couple days ago and couldn't wait any longer and pulled it out today (a Christmas present to myself). Low and behold there was an image on the paper! I scanned it, did some basic editing, and put it up on flickr. I made a couple new cameras that take a much larger piece of photo paper and am going to set it out tomorrow hopefully.

http://www.flickr.com/photos/aaronmichael/5291407866/

I've gotten images in as short as one day using a pinhole and exposing directly to Ilford paper.

Might be worth mentioning that you don't need to use a pinhole. I used a homemade lens/cigar box combination and got this in just about three hours:
http://www.dpchallenge.com/image.php?IMAGE_ID=913845

The aperture is about half an inch and focal length (depth of the box) is about four inches. So that's ~f/8. Again the exposure was direct to Ilford paper.

bvy said:

I've gotten images in as short as one day using a pinhole and exposing directly to Ilford paper.

Might be worth mentioning that you don't need to use a pinhole. I used a homemade lens/cigar box combination and got this in just about three hours:
http://www.dpchallenge.com/image.php?IMAGE_ID=913845

The aperture is about half an inch and focal length (depth of the box) is about four inches. So that's ~f/8. Again the exposure was direct to Ilford paper.

Click to expand...

Hm, interesting. Thank you very much for the reply. I got too anxious waiting for a reply so I tried it out using a film container pinhole and exposed for two days. Got a decent result but decided I wanted to expose for longer so I set up two new cameras on my roof. The main problem I have now is keeping water out of them. The actual camera is waterproof but the section I have cut out for the pinhole is not.