Re: [pinhole-discussion] re: Pinhole Camera Instructions... f/stops and needles
--- stephen wrote: > hi phillip > curious to know what are you using to create the > pinhole? > or do you know the approx f/stop? I use squares of aluminum cut out of old pop cans or disposable baking pans, and a pinhole "drill" made of a needle stuck in a pencil eraser. I spin the needle in the aluminum until the point just goes through, then sand the opposide side a little and drill from that side a couple of turns. After doing this drill/sand routine 2-3 times, I usually have a nice clean round hole. For 35mm I only get the point of the needle through, not the body of the needle, because I want a small hole. For these cameras, I don't worry about what f-stop I've really got: I just try them. With print film (lots of lattitude) and my exposure chart, I rarely see unprintable pictures: a first time pinholer I gave one of my cameras & instructions to on world pinhole day got a whole roll of printable pictures! -- PA __ Do you Yahoo!? Yahoo! Calendar - Free online calendar with sync to Outlook(TM). http://calendar.yahoo.com
Re: [pinhole-discussion] re: Pinhole Camera Instructions... f/stops and needles
- Original Message - From: "stephen" > hi phillip I am not Phillip, but pls allow me to try to answer your question: > curious to know what are you using to create the > pinhole? > or do you know the approx f/stop? > well, that is the question isnt it? > so many different charts have this or that f/stop > assigned to a fixed sized. > so has anyone come accross an 'accurate' mm (or inch) > to f/stop guide? There are several ways to find the f/stop of your pinhole camera set up. One method is to shoot an "average" scene under a sunny day, bracket several exposures and record the different times, process the film and select the "best" exposure, then find the f/stop of your pinhole making use of the fact that under sunny skies f/16 @ 1/iso seconds is the "correct" exposure. Another method is by knowing the diameter of your pinhole, then the f/stop will be given by the quotient of the distance between pinhole and film and the diameter of the pinhole. The hard part is measuring the pinhole. Knowing the diameter of needles you use to make the pinholes is a way to get an approximate size of the pinhole, measuring the pinhole itself is even more accurate. I wrote a small article on how to measure pinholes using your cheap (mine is anyway) flatbed scanner, what you then do is make a bunch of pinholes, measure them and use the one that approximates best to what you need. Here is the link to the small article: http://members.rogers.com/penate/diameter.htm > where can i get a #10 (0.46 mm/0.018 in) needle? > thanks! I know the following doesn't answer your question directly, but it may, indirectly: If you own a dremel or similar drill, you could also use wire gauge drill bits, a wire gauge drill bit #77 is 0.018" exactly what you need. see this 2 sets, for instance: http://www.mytoolstore.com/irwin/numbers.html there may be cheaper sets out there. Guillermo
Re: [pinhole-discussion] re: Pinhole Camera Instructions... f/stops and needles
You can also find them in Wal Mart in the craft section. They usually come in a package of several different sizes ranging from 5 -10, etc. They will have the larger diameter (smaller number) and then a smaller diameter (larger number) separated by a slash such as "5/10". The #10 usually does correspond to the 0.018" diameter as I have used these and tested the holes that they make and measured them and they are accurate enough. Just remember that the smaller the needle number, the larger is the diameter of the needle. > ive only been able to find sewing machine replacement > needles with numbers but these are larger than what > the mm size given in renners pinhole photography book > (p 118, figure 5.21a) > where can i get a #10 (0.46 mm/0.018 in) needle? > thanks! >
RE: [pinhole-discussion] re: Pinhole Camera Instructions... f/stops and needles
Hi Stpehen, Try a Michael's Craft store if there is one in your area. They are a big chain; but I don't know if they are nationwide. Tom Miller stephen wrote: where can i get a #10 (0.46 mm/0.018 in) needle? thanks!
[pinhole-discussion] re: Pinhole Camera Instructions... f/stops and needles
hi phillip curious to know what are you using to create the pinhole? or do you know the approx f/stop? well, that is the question isnt it? so many different charts have this or that f/stop assigned to a fixed sized. so has anyone come accross an 'accurate' mm (or inch) to f/stop guide? and has anyone found a source for numbered needles, or even know what size common pins or needles are in mm or inches? ive only been able to find sewing machine replacement needles with numbers but these are larger than what the mm size given in renners pinhole photography book (p 118, figure 5.21a) where can i get a #10 (0.46 mm/0.018 in) needle? thanks! re: I wrote these up for some 35 mm pinhole cameras I gave away recently, some for world pinhole day -- if you can use them, feel free. -- pw Pinhole Camera Instructions __ Do you Yahoo!? Yahoo! Calendar - Free online calendar with sync to Outlook(TM). http://calendar.yahoo.com
Re: [pinhole-discussion] 110 film sources?
Hello, Thanks all for the information on film availability. My local sources turned out to be far more limited than I first thought. I need to get to the city more often, huh?! A call to my local Wal-Mart photo lab left some young "technician" baffled. "110 film? Never heard of it. We don't sell the big stuff?" I'm guessing that he was trying to do a 35mm to 110 in a physical size comparison or something. I'll call back tomorrow and talk with someone that can be of help. If no local sources are available, I'll certainly try those that everyone has listed. Thanks! Later, Trent, in small town America Philip willarney wrote: > Hmm... I've made a number of pinhole cameras from the > larger 126 instamatic film -- still available at > > http://www.frugalphotographer.com/index.htm > > But there are plans for a 110 film camera at > > http://pinholespy.com/ > > I still see 110 film in stores from time to time -- > this place seems to have it... > > http://www.kcamera.com/main/invnew/newfc1.htm > > -- pw
