Peephole? Or 35mm Adapter? at DVinfo.net

Wayne Franklin · March 18th, 2006, 10:34 AM

I've been aware of some of the higher-end DOF adapters for a while now, but I'm new to the DIY approach you guys have pioneered here. (Kudos, BTW!) Lurking on the forums for the past couple of days and taking in so much info on close-up kits, achromats and ground glasses brought to mind something interesting I once saw in a bank. These large peepholes seem to have very low light loss:

http://www.doorscopes.com

I can't speak to actual light loss or optical quality, as I haven't bought one yet, but the large rear element seems to combine a 2" diameter achromat and a GG in one element. Do you think you could slap one of those critters in a tube, shake it around and get a decent adapter?

Andrew Todd · March 18th, 2006, 10:49 AM

for the vibration you would want to only vibrate the ground glass.. these things seem pretty cool.. but i dont know how youd get the screen to vibrate.

Wayne Franklin · March 18th, 2006, 03:33 PM

I found this discussion about the optics of the Door Scope and it's ability to produce an upright (but horizontally flopped) image. It uses something called a "dove prism."

Check it out here:

http://www.opticsnotes.com/sciopticsfaq/mirror.htm

Jim Lafferty · March 18th, 2006, 05:33 PM

Search "dove prism" on this forum... also, "roof prism" and "roof pentaprism".

Wayne Franklin · March 19th, 2006, 04:43 PM

Yeah, I've been reading up on those, Jim. (Sorry for the slow uptake.) Does the roof pentprism seem to be the preferred method for everyone here? Or the magnet trick on the LCD?

March 18th, 2006, 10:34 AM	#1
Wayne Franklin New Boot Join Date: Mar 2006 Location: Birmingham, AL Posts: 5	Peephole? Or 35mm Adapter? I've been aware of some of the higher-end DOF adapters for a while now, but I'm new to the DIY approach you guys have pioneered here. (Kudos, BTW!) Lurking on the forums for the past couple of days and taking in so much info on close-up kits, achromats and ground glasses brought to mind something interesting I once saw in a bank. These large peepholes seem to have very low light loss: http://www.doorscopes.com I can't speak to actual light loss or optical quality, as I haven't bought one yet, but the large rear element seems to combine a 2" diameter achromat and a GG in one element. Do you think you could slap one of those critters in a tube, shake it around and get a decent adapter?

March 18th, 2006, 10:49 AM	#2
Andrew Todd Major Player Join Date: Oct 2005 Location: Saint John, CANADA Posts: 633	for the vibration you would want to only vibrate the ground glass.. these things seem pretty cool.. but i dont know how youd get the screen to vibrate. __________________ video : xl2 / letus35xl / bogen 503 photo- canon 1dmkII - bronica etrsi

March 18th, 2006, 03:33 PM	#3
Wayne Franklin New Boot Join Date: Mar 2006 Location: Birmingham, AL Posts: 5	More interesting info on the Door Scopes I found this discussion about the optics of the Door Scope and it's ability to produce an upright (but horizontally flopped) image. It uses something called a "dove prism." Check it out here: http://www.opticsnotes.com/sciopticsfaq/mirror.htm

March 18th, 2006, 05:33 PM	#4
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	Search "dove prism" on this forum... also, "roof prism" and "roof pentaprism". __________________ Realism, anyway, is never exactly the same as reality, and in the cinema it is of necessity faked. -- J-L G

March 19th, 2006, 04:43 PM	#5
Wayne Franklin New Boot Join Date: Mar 2006 Location: Birmingham, AL Posts: 5	Yeah, I've been reading up on those, Jim. (Sorry for the slow uptake.) Does the roof pentprism seem to be the preferred method for everyone here? Or the magnet trick on the LCD?