Newton Rings

Published : 4th May 2004

I've heard that sandwiching filters in a Panavision ARF can generate strange Newton Rings. I once worked for a 1st AC who had us apply camera tape to the corners of each filter before placing it into the ARF (to put a slight distance between layers of glass).

Any truth to this?

Thanks,

Eric D. Anderson
Assistant Camera / Los Angeles

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Newton rings are a possibility but I've only seen it once in 35 years.

Most of my two hundred plus filters are taped on the edges to guard against this and, more importantly, it keeps the edges and corners form being chipped.

Steve Peterson
Dynalens Rentals
1st AC/ Los Angeles

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>I've heard that sandwiching filters in a Panavision ARF can generate >strange Newton Rings.

I have had to stack three Tiffen filters into two Arri trays many times. I have never experienced problems with Newtons rings.

Angelo Sartore
1st. AC
Melbourne
AUSTRALIA

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What is a Newton ring?

Anna Carrington
Camera Assistant
London/South East

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It is an optical interference band pattern in the form of irregular concentric rings of coloured light, which happens when there is an imperfect contact between two flat transparent surfaces and the separation between them is in the order of the wavelength of the light passing through them.

Arturo Briones-Carcaré (still alive and being kicked)
Filmmaker
Madrid (Imperial - but starting to recivilise - Spain)

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Newtons Rings :

http://www.physics.mun.ca/~cdeacon/labs/2054/nrings.pdf

http://sol.sci.uop.edu/~jfalward/lightinterference/lightinterference.html

http://www.rit.edu/~bekpph/Optics/8_Interference.html

John Pytlak
EI Customer Technical Services
Eastman Kodak Company
http://www.kodak.com/go/motion

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