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July 5th, 2013, 10:20 PM | #1 |
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What's Wrong with this Picture (literally)?
It seems like every Sony camera I own z5, nx5 and this PMW200 has barrel distortion. Does anyone see this in their cameras?
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July 6th, 2013, 02:21 AM | #2 |
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Re: What's Wrong with this Picture (literally)?
Show me a video camera with a 12x or greater zoom range that doesn't have any barrel distortion when wide. It's extremely expensive to design a wide angle lens with zero geometric distortion. I just spent $8K on a 16-28mm lens that has zero distortion at 24mm, but that's only a 1.5x zoom and cost as much as a PMW-200.
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July 6th, 2013, 09:21 AM | #3 |
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Re: What's Wrong with this Picture (literally)?
I just never seem to see this type of distortion with even the inexpensive DSLR lenses I own.
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July 6th, 2013, 02:32 PM | #4 |
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Re: What's Wrong with this Picture (literally)?
Are they 14x zoom lenses and your 20mm lenses have no distortion?
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July 6th, 2013, 03:31 PM | #5 |
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Re: What's Wrong with this Picture (literally)?
I've never had this distortion on any camera I've owned, still or video apart from wide angles, where it's normal. 12-18x zooms have never had this on the B4 sizes, and neither have the cheaper handycams?
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July 6th, 2013, 10:24 PM | #6 |
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Re: What's Wrong with this Picture (literally)?
and that shot didn't look especially wide. More like 50mm.
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July 7th, 2013, 12:07 PM | #7 |
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Re: What's Wrong with this Picture (literally)?
well regardless, you have it, and if you have adobe just throw a barrel distortion filter on it with some negative values and it'll be gone
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July 7th, 2013, 02:40 PM | #8 |
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Re: What's Wrong with this Picture (literally)?
The shot was fully open so I believe that is around 18mm. You cannot use any software to correct on a shoot that is changing its zoom because the barrel distortion amount is constantly changing depending on zoom amount. Also it can turn a 1 hour render to a 10 hour render.
Last edited by Keith Forman; July 7th, 2013 at 03:19 PM. |
July 9th, 2013, 01:25 PM | #9 |
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Re: What's Wrong with this Picture (literally)?
I think you guys need to do a simple look at the many lens reviews on the internet. Just look at the superzooms and the distortion they have. For example the Tamron 18-270mm (comparable focal length range to the PMW-200) has 0.75% barrel distortion at the wide end, The sigma 18-250 has 0.8% wave distortion and the Canon 18-250 has 0.9% barrel distortion, these are all significant amounts and just as noticeable in a shot with clear horizontal lines as the example given here.
Sure a B4 lens may have less distortion, it won't be zero and the lens will likely cost almost double the price of a PMW-200/EX1. Spend enough money and you can minimise lens distortion, but the EX1/3 PMW-200 etc are built to a price point. Would you pay $20K for a PMW-200 just to get less distortion?
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July 9th, 2013, 09:55 PM | #10 |
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Re: What's Wrong with this Picture (literally)?
I talked to support at Sony and they are examining the picture. I'll let everyone know what they say. I have the same shoot this Friday and I am going to try closing the lens zoom a bit and see if there is any noticeable reduction. If I have a chance I will use one of my other cameras and make an a/b comparison.
If time permits I will bring my FS100 and use the kit lens to make an a/b comparison this Friday when I am at the same venue. |
July 9th, 2013, 10:33 PM | #11 |
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Re: What's Wrong with this Picture (literally)?
Sometimes we have to work within our means. The perfect zoom lens may be a 20mm prime lens with a zoom range of about zero, give or take a bit of focus breathing. For what they are, I think this Sony family of cameras and companion lenses do a pretty good job in terms of cost/performance and convenient agility.
I don't know the circumstance in which you are using the footage. Is it simply a continuous single-camera event coverage of a match for a historical record? If it is more than that, compositionally, that camera position would not be my first choice. My personal preference would be to have the camera much higher or lower. For such a wide shot and for most convenient coverage, my personal preference would be to go into a corner, much higher if the players are to do all the motion work for your vision with minimal camera movement. It would convey more of a sense of the patterns of the game play if that is what you are covering. I would also use this position as an attempt to disguise any distortion as oblique lines. From the viewpoint you have chosen, if there were no means to go higher, my personal preference would be to go much lower to floor level almost, place the opposite floor/wall border towards bottom quarter or third of frame. This should hopefully put some of the far background straight lines closer to horizontal frame center and accentuate the distortion "arch" of the upper structure of the venue in top of frame, a sort of complimentary container for the moving subjects. This position would not work very well for visualising the patterns of game play as people coming closer to the camera will obscure the action behind them. I realise that your camera position may be the only one permitted by the event and you may have to make best of poor options. Please do not pay much heed to my comments but instead take notice of the more competent and accomplished people who respond. Last edited by Bob Hart; July 9th, 2013 at 10:45 PM. Reason: errors |
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