GH4 First look at 24p anamorphic & V-Log on GH4

I'm definitely not talking about barrel distortion, but the whole image skewed to one angle. This shot below for example is the most obvious one to me. I've added perfectly vertical lines for illustration. At the start of the pan, it seems like maybe the poles are just at an angle naturally because they are leaning in the ground, but as the shot continues to pan you can see that the building is also slanting to the right, and the car appears to be slanted to the right as well. It's not barrel distortion at the outer edges of the frame, but the entirety of the shot slanted to the right.

1.jpg
1 with lines.jpg
2.jpg
2 with lines.jpg

This isn't the first anamorphic film shot on DSLR/mirrorless that has had this in a few shots.

refocusedmedia said:
Squeeze and desqueeze shouldn't introduce slant or skew into the image though. should it? It's a linear stretching process, not a shift in vertical geometry.
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The reason I thought that is because if some of these adapters don't have a consistent FOV through the entirely of their focus range, then that means when you are near focused it's 2x but far focused maybe it's 1.7x or something, but if you desqueeze all the footage for 2x then the shots that are actually 1.7x wouldn't be stretched out properly, and could result in the skew I'm talking about.

Another pretty extreme example from this video, this looks pretty obviously skewed to the left:
Screen Shot 2015-04-17 at 1.21.56 PM.jpg
And this one to the right:
Screen Shot 2015-04-17 at 1.22.43 PM.jpg
This one to the left:
Screen Shot 2015-04-17 at 1.23.42 PM.jpg

Sorry for my mess of images and attachments, don't quite understand the image embed on this board.
 

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In my limited experience with anamorphic lenses, I've only seen that caused by a misaligned lens, meaning it is not seated perfectly with the top of the lens at the top and the bottom perfectly at the bottom. It's been rotated slightly for one reason or another. Another tell tale symptom of this is that the horizontal flare is not parallel to the top and bottom edge of the frame, which you can see in the pic you posted with the red flare.

the reason you see it so often is because people who use adapters or a 2x projection lens are often eyeballing the alignment and not realizing it's off. with 2x you really have to nail it or you get skew. can't be rotated even slightly.
 
I thought it might be something like that Zak, it's what makes the most sense to me, but also seemed like it would be too simple to be the sole cause (though I suppose most of these example videos are people's first experience using anamorphic so it would make sense to be an oversight). The only reason I brought it up is because it stood out to me, and since the GH4 is getting better support I was looking at my options for shooting anamorphic and noticed, and wanted to be sure if it was simply a known limitation people have to deal with, or if it was user error or something similar that could be prevented.
 
To prevent a misalignment, I keep an LED flashlight in my lens case and use it to flare the lens when I'm seating the anamorphic lens to make sure it's perfectly perpendicular to the floor.
 
Illya Friedman said:
This seems an odd thing to attribute to Deakins
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Sorry, I could have sworn I read/watched something where he said he didn't like the distortion that comes with anamorphics. Ah well, must have been another cinematographer entirely then, I guess.

Sorry about the misinformation, guys!!!
 
Zak Forsman said:
I'm not crazy about the flares, but i do love the unique bokeh and distortions of anamorphic cinematography. and i love the combo of compressed space associated with longer focal lengths and the wider field of view from the anamorphic component that you can't get from matted spherical. roger deakins be damned!
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+1

Exactly how I feel about anamorphics.
Less the Deakins part. ^^
 
I was thinking about the rumored paid V-Log firmware. I think Panasonic just wants to see our reaction. If every single one of us is willing to pay 200 bucks, there's no way we'll get a free firmware.

IMO, Panasonic should get their R&D money back on hardware and give us the software for FREE. All the companies that I LOVE are doing this, be it Apple, RED or Blackmagic. The GH4 was a massive hit for Panasonic and they're back in the game big time.

Matt Frazer, you guys have done a great job with the GH4. Let's keep rolling those good vibes. Please keep the firmware updates FREE. If you do soo, you're be selling more cameras and everyone will be happy.

What do you guys think ?
 
I hear that all LOG files tend to create more noise in the shadows, and the GH4 does this with V-Log cause the GH4 13 stops DR (2 in the noise floor) so 11 usable...and the LOG allows the usable dynamic range to go higher (better highlight rolloffs etc...)
KINOKS explained this well a few pages back...anyways the control and dynamic range in the upper areas does look good in the examples I have seen, but there has to be a trade off...so the shadows have more detail, and more noise in the darker areas.

So maybe Panasonic could be looking at some type of noise reduction that seeks darker areas..(its simply speculation) but these days everyone on forums has a gripe about something or other...and you can bet your life that even tho the grading, and high lights will
be better, there will still be bucketloads of complaints about noise in the darker areas of the shadows.
So it makes sense for Panny to try and get this sorted out as far as possible...and within the sensors limitations, before they release it.
Thats ny guess.
 
If you are shooting anamorphic on the GH4, you need to level the adapter. Change your display view to show the level plane lines on your LCD. Then take your phone and turn on the flashlight. Position it just in front of the lens and point it straight down the barrel. The resultant flare needs to be perfectly in-line with the level guide lines. Rotate/adjust the adapter until they do. Poof you're aligned.
 
astromann said:
I hear that all LOG files tend to create more noise in the shadows, and the GH4 does this with V-Log cause the GH4 13 stops DR (2 in the noise floor) so 11 usable...and the LOG allows the usable dynamic range to go higher (better highlight rolloffs etc...)
KINOKS explained this well a few pages back...anyways the control and dynamic range in the upper areas does look good in the examples I have seen, but there has to be a trade off...so the shadows have more detail, and more noise in the darker areas.

So maybe Panasonic could be looking at some type of noise reduction that seeks darker areas..(its simply speculation) but these days everyone on forums has a gripe about something or other...and you can bet your life that even tho the grading, and high lights will
be better, there will still be bucketloads of complaints about noise in the darker areas of the shadows.
So it makes sense for Panny to try and get this sorted out as far as possible...and within the sensors limitations, before they release it.
Thats ny guess.
Click to expand...

Good points. I'd much rather they get it right rather than push out to appease the firmware update starving folks.
 
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