Anamorphic

[Prahlad Strickland]

If I shoot the raven at 4k HD, and use my zacuto gratical EYE to stretch while shooting, and use premiere or resolve to stretch in post...

I have a ISCO 1.5 single focus front.... i'm just wondering how much of the anamorphic image i'm missing due to crop factor and will there be a mathematical de stretch in post that teams up accurately?

 

[Phil Holland]

Keep in mind that the Isco 1.5X were very much a specialty lens designed to cover a full 36x24mm image plane, so if we are talking about what the lens was designed for you are indeed using a smaller image plane. The 1.5X is even off the beaten path of standard anamorphic 2X, 1.33X, and the revived 1.25X optics.

 

[Prahlad Strickland]

Keep in mind that the Isco 1.5X were very much a specialty lens designed to cover a full 36x24mm image plane, so if we are talking about what the lens was designed for you are indeed using a smaller image plane. The 1.5X is even off the beaten path of standard anamorphic 2X, 1.33X, and the revived 1.25X optics.

The 1.5 gets a crazy nice vibe, being a single focus adapter, it seems to be one of the few affordable options. You think it's possible to achieve this on the Raven, I'm just wondering if it's achievable. I understand it will be a crop of what i'm seeing on the dragon 6k,

 

[Dan Kanes]

Think of aspect ratio this way:

16:9 (aka 4KHD) = 1.78 aspect ratio

1.78x1.5=2.66 (which is really a classic format)...

Let's say you go 4.5K "full format" aka Open Gate...

that's a 2.13 aspect ratio x 1.5 = 3.2:1 aspect ratio (super wide)

one benefit of having the smaller sensor area is that you can theoretically use wider lenses before vignetting (or if you had the bigger format you might not need to use wider lenses to get more field of view)...

I wouldn't worry about it too much... if you like the images you get... then boom - there ya go.

But if you're on the fence about getting a Raven or something else... I dunno... Scarlet-W though...

I guess what I'm not understanding is... what is needed to achieve? What is our end goal here?

 

[Prahlad Strickland]

Cheers Dan.
Main thing i'm wanting is what i'm already getting, 1.5 iscorama, i guess i'm just worried i'm not stretching at the correct ratio and ending up with people slightly wider or narrower faces etc.

Seems like the available shooting resolution's are not primed for shooting anamorphic due to it's sensor size etc.

My understanding of ratio's is bad, and you've definitely cleared things up a lot.

Loving what i'm seeing, just want to make sure i'm de-squeezing correctly.

Think of aspect ratio this way:

16:9 (aka 4KHD) = 1.78 aspect ratio

1.78x1.5=2.66 (which is really a classic format)...

Let's say you go 4.5K "full format" aka Open Gate...

that's a 2.13 aspect ratio x 1.5 = 3.2:1 aspect ratio (super wide)

one benefit of having the smaller sensor area is that you can theoretically use wider lenses before vignetting (or if you had the bigger format you might not need to use wider lenses to get more field of view)...

I wouldn't worry about it too much... if you like the images you get... then boom - there ya go.

But if you're on the fence about getting a Raven or something else... I dunno... Scarlet-W though...

I guess what I'm not understanding is... what is needed to achieve? What is our end goal here?

 

[Dan Kanes]

No worries!

You can always go for a pixel level desqueeze on export - or if you have enough resolution, a vertical squeeze down...

So, let's use Raven Full format open gate as an example:

Stretch style:

4608x2160
4608x1.5 = 6912
Export at 6912x2160 (3.2:1 ultra widescreen)


Vertical squeeze down style:
4608x2160
2160 / 1.5 = 1440
Export at 4608x1440 (3.2:1 ultra widescreen)

For composition in the camera - does Raven have anamorphic desqueeze in the menus? If yes, I'd probably use the 1.33x desqueeze so you're most of the way there but a little skinny, or use an outboard monitor like the SmallHD 5 or 7 series which I believe have 1.5x desqueeze viewing option.

 

[Brandon Ruiz]

I owned an Iscorama 54 with a 1.5x squeeze for a long time and honestly don't even worry about getting the unsqueeze dimensions pixel perfect. The squeeze ratio is a rough estimate and varies based on things like focal length of the taking lens. I don't really believe in squeezing giving you more resolution than you started so I would just squeeze the vertical height in Premiere or Resolve to 66-70%.

1.5x is a beautiful compromise between the spherical feel of 1.33x and the limitations of 2x anamorphics on a 16x9 sensor.

 

[Dan Kanes]

Tito Ferradans also has a great blog on DIY anamorphic solutions, workflow, DIY construction, etc.

 

[Satsuki Murashige]

Note that the Iscorama 36 1.5x does not maintain a constant squeeze ratio of 1.5x throughout its focusing range. As you focus closer, the squeeze ratio will fall short of 1.5x. This is typical of many older non-Panavision 'scope lenses and is a phenomenon known as 'anamorphic mumps' since it can lead to fat-looking faces once the images are un-squeezed by a constant factor of 1.5x. Since most close-ups are shot in the 5-8' range, those shots will be un-squeezed too much. My personal workaround for this is to unsqueeze Iscorama footage by 1.4x, which results in normal looking close-ups and slightly skinny-looking wider shots. But to each their own.

Aspect ratio is a related but separate issue. Depending on the camera format aspect ratio (for example, 4KHD 3840x2160 = 1.78:1), and squeeze ratio (for example, 1.4x), the final project aspect ratio will be (3840/2160 x 1.4 = 2.49:1). This is not a standard DCI aspect ratio (1.78, 1.85, 2.39:1), so if you wish to conform to one of those, then you would need to crop in post. Or if you want to stick with a non-standard ratio for web delivery, then you could choose to leave it as is.

The important thing is to decide ahead of time which project aspect ratio you would like to deliver to, and then optimize all of the camera settings and workflow for that. You can set up custom frame guides in Red cameras which makes framing for non-standard aspect ratios or non-standard anamorphic squeeze ratios much easier while shooting.