Advanced use

Set the camera lens

To properly set DragonFrame with the characteristics of a specific camera lens, you must know two of its "measurements" (see the section Calibrate the camera lens). You must then set accordingly the configuration window of the axis in DragonFrame.

Set the step number:

The previous part allowed to calculate the ratio between the drive module's gear and the one on the focus ring. Knowing that it takes 6000 steps for the motor to make the drive module's gear a full rotation, it takes 6000 x ratio to make the focus ring a full rotation.
At this point, there are two choices: directly enter this value with "Rot" as a unit, or divide the value by 360 with "Deg" as unit. For the choosen example of the previous section, the result would be 6000 x 2,694 = 16164 steps by rotation or 44.9 steps by degree.
Choosing "Rot" gives a more accurate result, especially to then set the limits.
Choose "Deg" gives a more natural and easy to interpret result but less accurate as DragonFrame only accepts integers – it is unfortunately not possible to enter a floating point value.

Parametre nombre de pas par unité

Setting limits:

If you followed the previous part, you also know the rotation's amplitude of the focus ring between the nearest and the farest focus distance. In the configuration window of the axis, at the bottom right, check the two "Soft Limits" checkboxes. Leave the first of the two values to zero.
In the second, if the selected units are of "rot" type, directly enter the number found in the previous step. If they are of "Deg" type, first multiply the value by 360. For the chosen example, it would give 0,4366 Rot or 157,176 Deg.

Parametre Limites

You may not be able to enter a floating point value for the upper limit – some versions of DragonFrame accept only integers. To do so nevertheless, uncheck the upper limit and then close the axis Setup window. In the axis options bar, double click on the digits indicating the actual position of the engine (in white) and enter the upper limit value. Once the motor positioned, click on the menu of the axis and choose 'Define upper limit'.
Now, DragonFrame is set 1) to give rotation's value of the focus ring and 2) not to exceed the limits of the camera lens' amplitude. Once these settings are done, you can definitely save the settings in a file: still in the configuration window of the axis, click the 'Preset' drop-down list in the upper-right area of the window, choose "Save as" and select where to save the file. If you save one file for each camera lens, you will be able to change quickly and reliably camera lenses.

Leave a Reply

Your email address will not be published. Fields marked with * are required