what distortion? (1 Viewer)

gwsudiro

Well-known member

• Apr 19, 2010

• #1

hello... ^_^

when panning, but not all the time, I noticed an object size become larger when it reaches center of field and then become smaller when it reaches the edge...only notice this when panning...

is this pincushion? if yes,is it normal to have it at that kind of degree..?? I always think that pincushion distortion only noticed when we look for it, in my case, I accidentally spontaneously see it...

many thanks before for your kind help...^^

best regards

Galih

 

Tero

Retired

• Apr 19, 2010

• #2

Would help to know what model. The objects should stay sharp even if they change size or shape.

 

pete_gamby

Birds? What Birds?!

• Apr 19, 2010

• #3

That would be the "rolling ball" or globe effect surely? A factor of the human visual system processing motion combined with the optics and dependent on the speed of panning (faster = more noticeable, static = no effect).

*awaits flames *

 

Kevin Purcell

Well-known member

• Apr 19, 2010

• #4

Search for Holger Merlitz on this forum for a detail explanation.

Pincushion counteracts rolling globe. Lack of pincushion in a bin makes more people see it.

 

gwsudiro

Well-known member

• Apr 20, 2010

• #5

hello all....^_^

hi Tero, it's a Zeiss FL 10x32, the image remain sharp though....

hi mr.Gamby, mr.Purcell, so, Zeiss FL 10x32's lack of pincushion?? how about barrel distortion? just have read, the description of barrel distortion seems matches my case...

I noticed it only when panning, not every time, not in every objects...

many thanks before for your kind help...^^

besr regards

Galih

 

Tero

Retired

• Apr 20, 2010

• #6

Have not looked at that one. All the Zeiss I have seen were bigger. But it is difficult to make a 10x32, it is just small for 10x. So not surprising if they put pincushion in it. I used to think that 10x was best, and went through 10x36 Nikon, 10x42 Nikon etc etc. I still have 10x42s, but use various 8x more.

Compare to the 8x32 Zeiss if you can. Maybe you will like it better. See
http://www.birdforum.net/showthread.php?t=161257&highlight=Zeiss+8x32

 

gwsudiro

Well-known member

• Apr 20, 2010

• #7

hi Tero, ^_^

I've just rechecked again, I think it's not barrel or rolling globe....when I look at straight pole, when I move it to the edge, I noticed that the top and the bottom of the pole bent toward edge, like it sucked to the edge but the center of pole ''remains in position''....maybe it causes few particular objects (in my eyes) looks bigger/stretched in center and shrinked/smaller in the edge....

that's pincushion right?

but what makes me worry is, there is so small of fov which keep the image/objects remain undistorted, is this normal with Zeiss FL 10x32?? or I just not familier to Zeiss' image character?

I used to have Swarovski 10x42EL, and I think it has very ''neat'' image compared to FL10x32....is this the problem??

help please....T_T

many thanks before....

Galih

 

Last edited: Apr 20, 2010

Tero

Retired

• Apr 20, 2010

• #8

Not sure, have not seen it, but most likely a feature of the 10x32. The 8x32 may not have it. But yes, pincushion it is. Are you wearing glasses, by the way? Some eye glasses may enhance this effect.

 

gwsudiro

Well-known member

• Apr 20, 2010

• #9

Tero said:

Not sure, have not seen it, but most likely a feature of the 10x32. The 8x32 may not have it. But yes, pincushion it is. Are you wearing glasses, by the way? Some eye glasses may enhance this effect.

Click to expand...

hi Tero, ^_^

no, I'm not a glasses wearer.....so, it's my eyes fault (the problem lying on the eyes of beholder?)?? I hope that's not the bins' defect....

best regards

Galih

 

gwsudiro

Well-known member

• Apr 28, 2010

• #10

read after read...I think it's not pincushion that distracting me x_x....maybe it's angular distortion....objects seem strectched out at edges....

best regards

Galih

 

birdazzLED

Well-known member

• Apr 28, 2010

• #11

That globe effect makes me a little nauseous.

 

gwsudiro

Well-known member

• Apr 29, 2010

• #12

hi BirdazzLed..^_^

so, rolling globe = angular magnification distortion ??

many thanks before...

best regards

Galih

 

Kevin Purcell

Well-known member

• Apr 29, 2010

• #13

No. The angular magnification distortion (bigger at the edges) is pincushion added to counteract rolling globe.

Rolling globe is a perceptual phenomenon.

I've just rechecked again, I think it's not barrel or rolling globe....when I look at straight pole, when I move it to the edge, I noticed that the top and the bottom of the pole bent toward edge, like it sucked to the edge but the center of pole ''remains in position''....maybe it causes few particular objects (in my eyes) looks bigger/stretched in center and shrinked/smaller in the edge....

Click to expand...

That's pincushion distortion.

http://en.wikipedia.org/wiki/Distortion_(optics)

http://en.wikipedia.org/wiki/Globe_effect

 

gwsudiro

Well-known member

• Apr 29, 2010

• #14

hi mr.Purcell...^_^

so, angular magnification distortion = pincushion distortion ??

many thanks before..

Galih