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anamorphic camera rotate / image skew

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Hi,

 

Is it just me, or must you shoot absolutely level to your horizon in order to prevent some image skew/distortion that seems to happen when you are slightly off being level to the ground?

 

Seems more prominent in handheld obviously.

 

Cheers,

- anamorph newbie

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First, as already stated, make sure that the anamorphic lens is aligned correctly with the camera/lens and make sure that it doesn't rotate for any reason(rotating front lens element for example).

 

Second make sure you are de-squeezing with the proper ratio for your anamorphic, 1.33, 1.5 or 2.0.

 

If have been done and you still notice distortion it can be 1 of 2 things.

 

1. Anamorphics can have extreme barrel like distortion at wide focal lengths on the edges that may have to be corrected for by removing some lens distortion. I mostly notice this in panning shots.

 

2. Determine the effective squeeze factor of your anamorphic. When I first started I had a giant projection lens with a 2x squeeze. Due to mounting with clamps and stepping rings it ended up having only a 1.8X stretch. The easiest way to determine the stretch factor is to take a photo perpendicular to a circular object, I used a CD. Take that image into a photo editing app and measure the width and height of the circle, which will be an oval due to the squeeze. Now you can take the height and divide it by the width to get the actual stretch factor and use that instead.

 

stretch = height/width

 

 

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Hi guys, thanks for all the posts. I feel like such a newbie but why reinvent the wheel right? Better to ask the pros!  :)

 

I am using pre-36 (isco brand front and rear) and admit I haven't had much time to play with it after selling a couple limbs to pay for it. But I hope to get it back on the camera soon and shoot some clips.  Any suggestions for "good" things to shoot?

 

Cheers,

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People on the streets. That's what I'm going to do. We already have a christmas market (little shops) built on the main street of the city so there are going to be a lot of people looking for presents. Many people, various objects in the shops and even some christmas lighting. Damn, they start this whole business a little too early... :) Do some shallow DoF shots with light in the background.

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My opinion is that the anamorphic shooting is not really suited for handheld shots. At first I was really caught on choosing the right stretch, but now I opt for stretch that looks just right to me (not necesarry the exact one). I think that is also a magic of it, not being always on 100% real measure. I edit mainly in Vegas, there's SONY DISTORT effect plugin, shifting only Y axis - when necesarry...

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The squeeze varies yes, usually it gets lower at closer distances (for example 2x at infinity and ~1.66x at 1.5m for my Sun). You can use diopters for close up shots, you can have your gear focused at infinity, this way your squeeze factor remains 2x.

Thanks for the reply Gabor. Yes this is pretty much what I have found. I suppose once you know the rules you can work around it. Diopters, Longer lenses for close ups perhaps.

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