Re: [pinhole-discussion] Human eye
On 22 Jul 2002, at 11:16, eco...@aol.com wrote: I know this is not strictly pinhole, but I wondered if anyone had access to the average human eye values for the camera variables. ie Respective - film speed, shutter speed, aperture, focus range, depth of field etc. Thanks Ellis Difficult to answer this one (though some will try) because the human brain does so much post processing. Neasurements of eyeball parameters such as resolution or depth of field are largely meaningless; that is, we see much better than eyeball specifications would indicate. For example, no matter what the eyeball's depth of field, we perceive our 'depth of field' to be infinite because that which we attend is always in focus, and the brain fills in the rest to make it seem so. Our 'focal range' changes with age. Young people can see as close as a few centimeters -- older folks may struggle with a meter or more. Our 'film speed' is continuously variable -- a dark adapted eye can detect just a few photons yet we can also operate well on a sunny day at the beach -- this is far more change than can be accommodated by changes in our 'f-stop setting' (iris diameter). Even our 'shutter speeds' can seem extremely short because for the most part we see even fast-moving objects clearly and unblurred thanks to the image processing our brains do. Regards, Gary Nored
[pinhole-discussion] #80 drill bit question
Okay, so I ran out and got a #80 drill bit to try. Are you all putting these in your drill? I'm worried I'll break it when I tighten the chuck. Plus, I can't seem to get it in straight, which would make a bigger pinhole. Or are you sticking this in an eraser like the old fashion way? Thanks! Traci Bunkers
[pinhole-discussion] OT: Very large format Polaroid photography - Photo book on eBay
Hi friends, Happy New Year to all. For those interested in really large format Polaroid lens photography (ouch...!)work, I've spotted a book on eBay (not mine) by 13 Japanese photographers using 20x24 format Polaroid camera. Book title is: The Works with Polaroid 20 x 24: 1983-1986 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemcategory=1507item=7524458 74 Price is stiff ($85 starting bid) but the seller (kolo1) is really into rare and expensive photography books and this is pretty standard pricing for him. Best, Guy
Re: [pinhole-discussion] The next Epson scanner after the 2450?
- Original Message - From: Richard Heather rheat...@slonet.org To: pinhole-discussion@p at ??? Sent: Saturday, January 04, 2003 1:34 AM Subject: Re: [pinhole-discussion] The next Epson scanner after the 2450? I have a 2450. The resolution at 2800 gets grain with most films. Unless you shoot TechPan or Kodachrome 25 I doubt more rez will improve the image. Somehow TriX 5x7 (inches!) seems grainier than 35mm. Richard Heather That actually is good, the grainier the film looks the better the scan is (if that grain is the actual grain of the negative). Higher resolutions are not used to improve the image but to capture the image the way it actually is. BTW, you also see the film grainier if you see it with a enlarger focuser, it is the same thing. Remember that when you scan at a resolution of 2450 DPI, your monitor, assuming the resolution is 1024x768, can only display a rectangle 0.3 by 0.4 inches of the total area of the film, it is the equivalent of enlarging your 5x7 to 80x114 inches size. Guillermo
Re: [pinhole-discussion] The next Epson scanner after the 2450?
I have a 2450. The resolution at 2800 gets grain with most films. Unless you shoot TechPan or Kodachrome 25 I doubt more rez will improve the image. Somehow TriX 5x7 (inches!) seems grainier than 35mm. Richard Heather Subject: [pinhole-discussion] The next Epson scanner after the 2450? I've been trying to remember and searching the archive for, a reference made not long ago here, about a new Epson flat-bed scanner to hit the market soon. What was it called the Epson 3200? or 4800? It was said to be of higher res. than the current 2450. Who brought that up, because I want to review that info again for a possible future purchase of a flat-bed film scanner for Med./large format negs. Thanks for the help, Andrew Amundsen
