What's with the blue fringe, ghosting, halo etc.?

Rambos

Rambos

Member
Just wondering about this blue/purple fringe that keeps showing up on the HVX footage. Is this a camera issue or a lighting issue, or both? It seems to show up only on the left side of all the footage.

I've posted some samples from various clips in the forum.

blue_fringe.jpg
 
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Hey, someone actually looked at one of my stills!

Anywway. I think in the case of my shot (the one with our boy JC), it's due to being against sky with spill from that combined with edge enhancment increasing the contrast of the blue (I had my detail level set to +7). That's probably the case with the pic with the woman. The Owl and the the guy on the other hand not only have it appear much more prominantly (especially the Owl) but also against a white sky so I'm really not sure about those.
 
Thanks for your info. While the edge detail settings seem like it could be a culprit, it still doesn't make sense (since it's not something you actually want on your video) that it even happens at all. Considering it seems to only happen on the left side of the clips, would seem like this was a ccd or lens defect.
 
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This is a lens defect, and to some degree whether visible or not, is apparent in almost all lenses, however the HVX lens seems to really bring out this defect, but not as much as the stock HD100 lens. It is known as Chromatic abberation and is basically a missalignment in the lens that (on contrasty edges) shows up as a blue or reddish trim. there are plugins that can fix this, however their effeciency depends entirely on which editor and which format you are using.
 
All lowcost HD/SD cameras do this. you cannot get away from it, its part of why the cameras are cheap. The (probably) 500$ lenses on Prosumer HD cameras arent as awesome as the 60,000$ HD lenses you see used on big budget shoots.

Though i must admit, Some HVX's are more prone to it thatn others. Im REAL lucky. Mine isnt bad at all, where as on my working partners camera, it is visible.
 
well whats strange is that sometimes its there, and sometimes it isnt.

with a lens adapter on it, will that help rid the problem? I notice, that the more 3d the object is, the more the line shows,

or is it a color issue, or a luma issue?

with mine I noticed in shooting to tape ntsc is much worse than shooting on hd.

Jason
 
My understanding is that diffraction also tends to increase the effects of CA, so with small apertures the problem gets worse. In at least three of the shots in the original post, that might have factored into the results.
 
Jason Miller said:
has there been a fix for this issue?

other thank edge detail to -3, I still get it at times at -3
Click to expand...

There is no "fix" other than avoiding saturated, high contrast scenes. Shots with sky backgrounds are notorious for this image defect.

What I find really interesting is the mod's comment about the unit-unit variation in CA problems. Hmmmmmmmmm ............. :huh:

Regards
JohnG
 
I wonder if this is the cause of the problems in the green screen studeo, It seems to be worse with a brightly lite back ground, only instead of a blue fringe, there are 2 lines, one white and one black, and they vary in thickness.

Jason
 
so would an adapter with a new lens effect it, it seems as if it should as the angle of light has changed, as has the amount of light.

Jason
 
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