Red 18-85mm - interesting flare

[david_winters]

Only get this effect when a light source is near / off the top of frame. Doesn't have the same effect near the bottom. I like it, it worked really well for this scene.

http://farm4.static.flickr.com/3575/3482768747_f279c783e1_o.jpg

http://farm4.static.flickr.com/3307/3482768689_d54c258264_o.jpg

[Florian Stadler]

I've gotten a similar flare with the Cooke S2 50mm. It was a tweenie going at subject from top frame right. I wonder if it's more of a angle of incident on the sensor in combination with focal lenght that causes this admittedly pretty artifact. What were the focal lenghts where this occured? Did it occur from frame left also?

[david_winters]

Anywhere along the top of frame. I think you are on to something, I was at approx 50mm for this shot. After looking again at the source footage it looks like the effect only occurs when the light source is just out of frame. Here is a better example. At wider focal lengths the effect is very very subtle.

http://www.innovatemedia.com/clips/winters/tests/18-85flare.mov

Dave

[Mike Prevette]

Can't think of any mechanical reason it should affect the bottom of the aperture (top of the frame) more then the top. At first I though it was just a bounce off the internals of the lens cavity.

[Evin Grant]

Could it be refection from the front mask?