About diffusion filters

Hi,
I watched the video on Tiffen diffusion filters and I don’t think I want to go down that road right now for various reasons.

I also watched a video of Arri using netting. It’s mounted in the back of the lens on a magnetic holder. I was wondering if there is a method for the 6k pro to make and mount something like this to work with the Milvus lenses. I see there is a baffle inside the camera with ridges, I’m assuming they function similarly to bellows on film cameras and are not threads.

Would it be possible to stretch the nylon over the entire back of the lens and then mount it? I don’t know if the fit would be too tight but there is some slight movement in the mount already so maybe it would fit better.

Any thoughts are appreciated.
C

I’d advise caution though – it’s nearly impossible to manually reproduce consistency of the net stretching using the above method.

If you’re only interested in net diffusion, and want consistency, then I’d recommend giving Schneider’s True-Net a go. I use the True-Net Black and love it. The only issue with it – as with net diffusion itself – is the net patterns shows up in the footage when the lens aperture is closed down, and I never use it below T5.6.

Thanks much. I did find that video before but wasn’t sure it’s a good idea after looking at the rear of the lens. I wasn’t aware of the Tru-net filters, seems like they’re a better solution.

You may be able to improvise a fine net material across the rear of an anti-reflection cone which screws out of the throat of several of the BM cameras. You would do this by stretching it across after applying adhesive, waiting for it to set firm then trimming the net material tidily for diametrical clearance so the material does not wrap over and bind the threads of the cone in the camera body.

I have done similar with an in-dwelling IRND filter except with net material, you will not be forced to set the lens mount forward to compensate optically for the thickness of an indwelling optical filter. You will need to make sure you do not screw the anti-reflection cone beyond a half millimetre short of fully home or the net material may abrade the blue IR filter disk or press against it and crack it.

You should be able to rotate the cone to orientate the signature linear flares of some net materals. If it is strung across a lens, you will not be able to do this unless you have used a filter frame to mount the net material.

Good luck with your endeavours.

You may be able to improvise a fine net material across the rear of an anti-reflection cone which screws out of the throat of several of the BM cameras. You would do this by stretching it across after applying adhesive, waiting for it to set firm then trimming the net material tidily for diametrical clearance so the material does not wrap over and bind the threads of the cone in the camera body.

I have done similar with an in-dwelling IRND filter except with net material, you will not be forced to set the lens mount forward to compensate optically for the thickness of an indwelling optical filter. You will need to make sure you do not screw the anti-reflection cone beyond a half millimetre short of fully home or the net material may abrade the blue IR filter disk or press against it and crack it.

You should be able to rotate the cone to orientate the signature linear flares of some net materals. If it is strung across a lens, you will not be able to do this unless you have used a filter frame to mount the net material.

Good luck with your endeavours.

Thanks.
There is a small shelf on the top of the cone that is behind the lens mounting so I took a measurement and I’m going to have a plastic ring printed and then glue the net to that to try it out. I looked at the Schneider solution but I’m not ready to go down that road, cost wise.

The price for the 3d printed part is $18. Worth trying.

Chris.

Please let us know how you get on with the arrangement you suggested.

Yes I will. I’m waiting for my order from McMaster to arrive. I purchased a square shaped o-ring. I have the fabric already. I’ll take pictures but any testing results are a ways off. I need a new computer to run Resolve 17.

Here is how I made one using flat black tule and a 1/16” square o-ring. The only thing is the type of adhesive used has to be able to stick to the rubber.

I sprayed it on the o-ring and set that on the fabric, then trimmed it.

I had to buy a 100 ct. pack so if anyone wants a couple to try let me know in a pm.

Here is how I made one...

Not bad at all.

Can you share some footage as well? I’d recommend pointing the camera directly at the midday sun and filming at all T stops between 4 and 22.

This does look like it can save many people a lot of money.

However, a major downside is that there may be a buildup of electrostatic charge on both sides of the fabric, which may in turn attract and deposit considerable fibres and dust particles on the sensor glass and the lens element.