[rollei_list] Re: Rolleiflex changes and a zeiss serial number for Marc


----- Original Message ----- From: "Peter K." <peterk727@xxxxxxxxx>
To: <rollei_list@xxxxxxxxxxxxx>
Sent: Thursday, October 26, 2006 11:49 AM
Subject: [rollei_list] Re: Rolleiflex changes and a zeiss serial number for Marc


Sounds like a great camera. The coating colors have to do with the glass
type used in each of the lenses.

Once you use a Planar you will know why I always say Planars rule!!

Peter K

That may be. Single coatings suppress reflection completely (or at least the maximum) at only one wavelength. The residual reflection is the compliment of the light the coating is peaked at. So, a magenta tint is found where the coating is peaked for green light, amber where it is peaked for Blue light. Often lenses will be found to have different residual reflections on different surfaces. I think this was done to try to equalize the transmission of the lens throughout the color range.
The index of the glass will be a factor in choosing the thickness of the coating. Ideally, one would have choice of coating materials with various indeces but the material must also be chosen to have the right mechanical and chemical properties.
For those with a knowledge of electronics coatings are very closely related to 1/4 wave transmission impedance matching networks or filters.

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx


---
Rollei List

- Post to rollei_list@xxxxxxxxxxxxx

- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org

- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org

- Online, searchable archives are available at
http://www.freelists.org/archives/rollei_list

Other related posts: