Hi, I recently was in iceland, did some auroral photography, and have noticed that regardless of film used, all photos in which an aurora appears have newton rings in the center of the film, of varying intensity. the equipment i am using is a pentax 67ii with the 55-100 zoom lens...the shots were at f4.5, smallest aperture on that lens....avg exposure maybe 30 seconds. I also took some night shots with no aurora present, and NO newton rings are detectable on the negative/slide. Does anyone have any experience with this, and how it might be avoided in the future?

Thanks,

Randall

-- randall thomas (dogfooddog@aol.com), January 24, 2002

Answers

I have gotten light areas in the center of the frame when using my 400 and 600 Takumars. Only happens once in a while and never off axis like a flare. It is not the typical red or green polygon that one would expect in a flare but a fuzzy area with no distinct edges. It seems to happen most when there is a light area in the scene, which is combined with a fairly dark region. The area where this fuzzy light area appears is always superimposed over a darker area in the scene.

-- Steve Rasmussen (srasmuss@flash.net), January 26, 2002.

doing some reading, apparently this is a common issue with aurora photography, there are some threads on this on photo.net, i used keywords aurora newton ring to find them on google.....I have yet to find a way of dodging them anywhere...next time will try faster film,wider aperture lens, and no filter and see what happens.

randall

-- randall thomas (dogfooddog@aol.com), January 24, 2002.