Yet another question about ND filter usage

[Deleted member 94047]

Same old tired topic but please hear me out for I am confused out of my wits. I put on an ND16 filter, I want to film at 60 fps, double that for the shutter speed, I get that; so I put the shutter speed at 1/120. I take a look at the EV value and see that the picture is way under exposed. I could, and probably should, take the ND16 off and put on an ND8 filter. But taking these filters on and off is such a hassle and every time I screw or unscrew one, I fear I am putting too much stress on the gimbal. Plus I don't have an ND8 filter (yet).

So instead of changing the ND filter, what if I reduce the fps I am filming at and decrease the shutter speed accordingly. Let's say I film at 24 fps instead and adjust the shutter speed to 1/50. Voila, now the picture is no longer underexposed even with the ND16 filter on. So, question is - is the choice of ND filter purely dependent on the frame rate you want to film at? Or am I missing something entirely here?

 

[THE CYBORG]

Is really boils down to how bright the lighting is at the time you are filming.

Lets say you have the ISO at 100, Frame rate at 25 you would fit whatever ND filter is appropriate at the time to get the desired shutter speed of 1/50.

Fit whatever filter gets you closest to the camera settings you have set.

 

[MAvic_South_Oz]

Filter fitment and choice are last to do, to bring exposure right with the FPS and shutter to where you want.
You should start with FPS and work from there . . . in general 24FPS is fine for general video.
FPS will depend on what video res you are shooting too, check through and see what FPS are available in the different resolutions.

Set iso as low as possible, 100 is great if you can manage it, usually ok for blue / golden hours.
Other things I usually set are white bal to sunny conditions (for outdoors, even with a little cloud).

You don't have to fit the filter to get it pretty much right, do you have the M2Z or Air with screw on filters ?
With all your settings in place, hold drone camera up towards the general light and see if the histogram is nicely bunched up centre.
If too high exposure, just hold a filter up in front of the camera lens (nice and tight) and see how it changes the histogram and appearance on the viewing device screen.

Check shutter, should be about 1/50 (using 24fps as an example).

I think I've got that right, haven't got the MP here at the moment to double check.

Have a good look through camera settings, there is the overexposure warning you can set too, and probably a few other little things to help get it right.

Hope that helps.
If unsure, search youtube typing in your mavic model camera settings (eg Mavic Air camera settings, or Mavic 2 zoom camera settings) and se what comes up.
I know there are a lot of great original Mavic Pro videos available using that search, I'm sure there would be many for the newer models too.

 

[Deleted member 94047]

Thank you Cyborg and Mavic South! I think I get the purpose of using an ND filter - it is to get your exposure down so that you can film at double the shutter speed of the frame rate. I was thinking of controlling the exposure with the shutter speed; in essence see what shutter speed will give me a good exposure and then pick a frame rate based on that. Seems a bit reverse and I was wondering if that would work. I see your points though, choose what format and frame rate to film with first and then reduce the exposure down to the level where the shutter speed is double the frame rate. Got it! Thanks again!

 

[brett8883]

Same old tired topic but please hear me out for I am confused out of my wits. I put on an ND16 filter, I want to film at 60 fps, double that for the shutter speed, I get that; so I put the shutter speed at 1/120. I take a look at the EV value and see that the picture is way under exposed. I could, and probably should, take the ND16 off and put on an ND8 filter. But taking these filters on and off is such a hassle and every time I screw or unscrew one, I fear I am putting too much stress on the gimbal. Plus I don't have an ND8 filter (yet).

So instead of changing the ND filter, what if I reduce the fps I am filming at and decrease the shutter speed accordingly. Let's say I film at 24 fps instead and adjust the shutter speed to 1/50. Voila, now the picture is no longer underexposed even with the ND16 filter on. So, question is - is the choice of ND filter purely dependent on the frame rate you want to film at? Or am I missing something entirely here?

You are getting it but don’t forget about ISO. Since you don’t have an ND8 you could bump iso up to 200 without any noise at all and up to 400 without making the video unusable.

So use the ND16 with your shutter set to double your frame rate and then adjust your ISO up to 400 to get your exposure right. And also -.7 to +.3 isn’t gonna hurt anything anyway if you plan to post process.

While not ideal the above will allow you to shoot high quality video without all the ND filters