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View Full Version : Dallmeyer 50mm f/0.8 #713810 8-14 Microns Multilayer Coated Lens REF:I3915



Miranda
05-24-2013, 02:40 PM
Can anyone help, I've stumbled across this lens on eBay, I've tried to find out more information using online catalogues but have drawn a blank so far. The seller knows nothing as came as a job lot with a thermal camera. Any information would be gratefully received :)

Ian Grant
05-24-2013, 03:44 PM
Welcome to APUG

It's a highly specialised lens for some kind of industrial use, it will be useless for conventional use. I have a 75mm f1.9 Dallmeyer that barely covers 35mm, mine's an oscilliscope lens. It's coatings indicate it's designed for something special, as you've indicated possibly thermal imaging.

I've quite a few adverts for Dallmeyer lenses but it's not listed. You'd need to look up lenses for thermal imaging.

Ian

Ian Grant
05-24-2013, 03:52 PM
Interesting a quick search shows thermal imaging lenses with similar blue coatings.

Ian

AgX
05-24-2013, 07:03 PM
What may this "8-14 Microns" refer too?

mr rusty
05-25-2013, 04:13 AM
What may this "8-14 Microns" refer too?

wavelength of light in the infra red section. Quick google shows humans emit infra red radiation at around 10 microns, so slap bang in the middle of this range. I think you have found what this lens was intended for.

Ian Grant
05-25-2013, 02:35 PM
The OP is the seller "mirandute" (http://www.ebay.co.uk/itm/Dallmeyer-50mm-f-0-8-713810-8-14-Microns-Multilayer-Coated-Lens-REF-I3915-/221231001822?pt=UK_Photography_VintagePhotography_ VintagePhotoAccessories&hash=item33826530de) I think :D

Ian

Miranda
05-26-2013, 08:18 AM
Nope genuine buyer, but can see why you thought that! I'll be honest I don't know much about lenses but this caught my eye as I know Dallmeyer Lens are collectable. I'm after a IR lens for a "project" but can't find anything technical about the lens. As it's almost certainly a IR lens I'm curious as to the lens material as glass is no good for this field of work, possibility of Germanium which explain the opaque lens.

Thanks for your help so far, I just wish to learn more about this lens, technical specs and year of manufacturer, several lenses like this have appeared on ebay from 500 to 30,000, none detail much information on the lens other then stamped markings.

Ian Grant
05-26-2013, 09:17 AM
That lens is highly specialised, Applied Photography, Focal Press, says that the 8-14 microns transmission band is used for thermal imaging of bodies too cool to emit near infra red. There's 3 other ranges 1.4 -1.9, 2.0 - 2.6 and 1.9 - 4.3 microns

0.3 - 1.38 microns covers the UV and visible light range as well as photographic infrared.

This lens isn't for film use it would have been used with some type photo cathode amplification device. Lenses like this are still made around the world and you can get a camera and lens for less than the asking price of this particular lens, it'll be digital though.

Pentax made a Nocta, ifra-red film camera,

Ian