Some other pinhole sites are:
You can use the formulas, but they vary, as others have said. I just find that f200 to f300 work well. Also, as SMBooth said, thinness is good.
Keep working at it, pinhole is fun and you're off to a good start. Next April, do something for Worldwide Pinhole Day http://www.pinholeday.org/
My piece of metal comes from a watch.Pretty thin but I can do better.I am still looking to find this type of parts of metal with tiny perfect holes.I am knew in photography, of course in pinhole too.Thank you for your advices, I will try to go over all of them.Maybe I can make my images sharper.
I use b&w 5mm ISO100 and colour film for ISO200.I got to feel what exposure I should use.About the composition, well it's harder.I just guess where the camera points at.And I think my angle of view is ~44.6degrees.
I just bought a Zenit E from an antiques sale, street market.Works perfect.I try to use it to see what the angle looks like in my viewfinder.I point and shoot and in my mind I have that composition for my sight, my 37 degrees angle.Sometimes you have to guess.
I went to many sites but still it is too hard to real use that info about your pinhole with your own, it is too hard to measure it or make it a perfect circle.That bugs me.BUT, what I love about this thing is that I will try to improve mine until I get it right!I am too close to having a perfect pinhole camera :).And of course, I love what I am doing.
Less is pinhole!
A note on measuring your pinhole diameter - you can scan the image at a high resolution (2000 dpi or so) enlarge the hell out of it and then use a graphics editor - Adobe etc, (GIMP is free) to determine the number of pixels the hole is. Based on your scan resolution you can determine what the per pixel width is and, in turn, the actual pinhole diameter. I've checked my holes with a microscope and and its proved to be a pretty darn accurate method.
Not "hating" as the younger folks say... but those photos are just too soft for me to have any interest in.
Do what you like though.
Two points. First, my guess is you mean 35mm. In my experience, and for what I try to accomplish via the pinhole medium, 35mm is too small of a negative to enlarge cleanly. They always look fuzzy. Try 120 film either with a home-made, converted or purchased camera and the enlargements will be much more clear.
Originally Posted by Kinetic
Second, I suspect that the watch metal is thick enough that you are getting the "tunnel effect." Light bounces off of the sides of the pinhole itself causing diffusion. Here is a link to a thread on f295 where Earl Johnson sells electron microscope slides mounted for use as pinhole. They are excellent, with thin metal and precise apertures; and they are cheap. I use them for nearly all of my own photos.
Kinetic! I think your images would have been even better for me if they were sharper (less Blurred).
I think the 0.40 is too big and 0.30mm might be a safer bet to get more details.
I am no expert but from browsing the web my gathering is that this hole should be smaller and there is an optimal which I am also hunting for.
I have been on 4 different sizes myself but still not happy.
Hard to get a perfect pinhole size, but I am sure trying :).Who has some old chinese watches that they do not use any more? :))
I've done a bit of pinhole, and 35mm just seems an exercise in frustration.
It can be done, but *much* better results await with larger formats, even with paper negatives.
Build your own, my 5x7 is literally a shoebox.
Also, check out f295.org, a superb pinhole site, the best, in my opinion
some overlap, but these are all 4x5 and 5x7:
I was never satisfied with the images I was able to obtain from my 35mm pinhole cameras.
I was not happy until I tried the larger formats.
I still don't how to use the paper or larger formats.I have no darkroom and no room for one.And don't know where to go and take them out.And it's too bad, I know, but what can I do? I just use my Obscura as it is and hope for the better.Looking for smaller holes in metal sheet.:))