Cristian Diaz

Hi there fellas!

I'm currently working on a feature film as a 2nd AC and there's someting the focus puller and I have been discussing for the past few days that we've been unable to puzzle out much as we try. The camera we're shooting with is the Alexa Mini LF and a set of Arri Ultra Primes. Here's the thing:

We were facing a shot involving two actors and at some point while measuring distances we broke bout pCAM app to compare the DoF of the LF we're using and the Alexa Mini. To our surprise the app showed greater DoF in the LF than in the Mini, which definitely made our heads blow:

Camera 1
Alexa Mini LF Open Gate
Focus Distance: 2,5m
Aperture: f4
Focal Length: 50mm
Total depth: 0,45m

Camera 2
Alexa Mini Open Gate
Focus Distance: 2,5m
Aperture: f4
Focal Length: 50mm
Total depth: 0,38m

What do you make of this? Shouldn't there supposed to be shallower depth of field with a greater sensor as of the LF? To my understanding the greater the sensor the shallower depth of field, but there's clearly something I'm missing here...

Please help! Your insight will be very much appreciated! Find attached the screenshots.

Thanks

Thank you all for your insight.

Hi all!

What does the 3 stand for when speaking of ND filters? I know each increase in multiple signifies a 1 f-stop, but never stopped to think why a 3 increase...

Thanks...

Thank you Bruce. So, assuming we have diffusion, ND and pola this would be the correct order...?

Hi all!

I was wondering what is in fact the best possible way to stack filters into the matte box concerning order...assuming we have to use lots of different types: nd, pola, difussion...

I know physics count as we are talking about cinematography here, so I would like to know if there is a 'right order' technically speaking, if any.

It would also be interesting to know if 'the right thing' didn't work for you on some occasion, whatever the reason and why.

Thoughts?

Thank you!

Thank you Alex for your insight and sorry for the late response. You've been of great help.

Hi all!

Thanks for letting me join the forum. It's a pleasure.

Shortly I will be shooting a low-budget shortfilm and most of the story takes place in day interior. I'd like to create a shaft of light through the main living room window. The question is - what would be the minimum required to create such an effect? I know my best shot is to use at least a 12K HMI Fresnel combined with some haze but I was wondering if M40 with 4K bulb or 6K bulb would be enough for that purpose.

Also the house is facing north and I was thinking of using a negative canopy above the HMI's to prevent the exterior sunlight from coming into the room, but I'm not entirely sure this will actually work.

In terms of exposure I believe I should expose for the window, right?

Any other tips related to haze, ideal angle etc will be more than welcome :)

Many thanks in advance.