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Frameline Generator Advanced FLAG

Thanks to multiple input options - pixel, aspect ratio, millimeter - the FLAG offers tremendous flexibility, does all conversions for you - and can be used as format calculator.

The FLAG creates xml files which need to be uploaded into the camera. These xml files can be easily shared, copied, archived, emailed - e.g. to your rental house prior to your next camera prep.

Even without loading xml files into the camera the FLAG can help to design format markings. It calculates custom values which you dial in manually by using the User Rectangle feature in the camera (User Rectangle supports full box framelines only).

The FLAG supports all the various sensor and shooting options ALEXA and AMIRA cameras are offering. Here is the complete list (as of Version 5.8.3) :

Description

The format lines in monitor outputs and electronic viewfinder of ALEXA and AMIRA cameras are generated by parsing xml files stored in the camera, not unlike a webbrowser which reads html files and displays them as webpages.

The exact shape of each frameline ist stored in a system of coordinates which describe the endpoints of a line in relation to the total image border, the left , right, top or bottom border.

The total image size depends on the sensor mode the camera is in (16:9, Open Gate etc.). For each sensor mode specific frameline description files are necessary, since the coordinates are different in each mode.

These coordinates are written as tag/value pairs in a markup language, in this case the “Extended Markup Language”, XML.

XML is a text format resulting in small files which can be easily shared by email.

Functions

User Rectangle

Creating framelines the quick and dirty way: Without generating and uploading an XML file into the camera you can dial in your custom frameline “on the fly”, by utilizing the “User Rectangle” function in the camera menu. The FLAG calculates the proper values based on your entry in Framelines and Offset.

The scheme for setting user rectangles is slightly different in ALEXA and AMIRA cameras:

These values are neither pixel nor millimeter, but in “promille” (0 to 999) of total image height resp. image width in the selected sensor mode.

Shading and Center Markers are not supported, they have to be set separately in the camera menu.

XML Code

A glance under the hood: This is the XML the FLAG generates based on your selections and settings. This code is stored in the text file the camera parses to display framelines in the electronic viewfinder and the monitor output.

It is not possible to edit the code in this preview, but you can easily copy and paste it into any text document. In case you feel the need to edit the code manually: be careful what you do, as some edits may not sit well with the camera and might produce unexpected results.

Camera

The ARRI family of digital cameras offers various image modes for a wide range of shooting and release options. In many of these modes the size of the active sensor area differs.

Therefore the framelines need to be generated specifically for the image mode you are shooting in.

Don’t worry if you need to change the selected camera or mode after you have specified your frameline: the FLAG will re-calulate the values based on your new selection. Only the Scale value will default back to 100%, and any offset value will be reset to zero.

Lens

When working with anamorphic lenses the image you see in the viewfinder (and later on screen) is wider than it is on the sensor. However, the frameline you are creating - and the frameline/sensor preview of the FLAG - represents the actual size and position of the image on the sensor.That's why the squeeze factor of the lens needs to be taken into account in order to generate the correct frameline for an anamorphic project.

The “classic” anamorphic format works with a 2 times horizontal squeeze. So this is what you will most likely select when shooting anamorphic.

There is, however, a specific series of Vantage HAWK lenses, which applies a 1.3 times squeeze to the image width, the beauty being that now 1:2.39 fits almost perfectly into a 16:9 frame.

And there is a set of 1.25x Panavision lenses for the ALEXA 65

In case you need to change the selected lens after you have specified your frameline: the FLAG will re-calulate the values based on your new selection. Only the Scale value will default back to 100%, and any offset value will be reset to zero.

Andreas Weeber, 2017-04-07