Alexander Sutton Hough Posted March 1, 2018 Share Posted March 1, 2018 What diffusion filter would be best to mimic the subtle diffusion look of an Arri Alexa on the Reds, Sony and Panasonic. Currently looking for some to us on a GH5s and Sony FS7. Link to comment Share on other sites More sharing options...
Premium Member David Mullen ASC Posted March 1, 2018 Premium Member Share Posted March 1, 2018 I don’t think the Alexa has a diffused look but if you want to lower contrast to match better, try the lightest Tiffen UltraCon. Link to comment Share on other sites More sharing options...
Alexander Sutton Hough Posted March 1, 2018 Author Share Posted March 1, 2018 I don’t think the Alexa has a diffused look but if you want to lower contrast to match better, try the lightest Tiffen UltraCon. But what about the slight softening of super fine detail compared to other digital cameras that makes it more pleasing on skin and film like? Link to comment Share on other sites More sharing options...
Premium Member David Mullen ASC Posted March 1, 2018 Premium Member Share Posted March 1, 2018 What slight softening are you talking about? Are you just referring to the limitations in resolution compared to +4K cameras or the lower contrast in the highlights that roll off to white more smoothly? Link to comment Share on other sites More sharing options...
Alexander Sutton Hough Posted March 1, 2018 Author Share Posted March 1, 2018 What slight softening are you talking about? Are you just referring to the limitations in resolution compared to +4K cameras or the lower contrast in the highlights that roll off to white more smoothly? The effect its Optical Low Pass Filter causes? Doesn't the Alexa's OLPF contribute to its filmic look by slightly softening fine detail and lowering the contrast? Link to comment Share on other sites More sharing options...
Premium Member David Mullen ASC Posted March 1, 2018 Premium Member Share Posted March 1, 2018 That's what Red claims but ARRI denies it. All OLPF's soften fine detail, that's what they are designed to do to minimize aliasing, but Red cameras don't use a milder OLPF than ARRI's do (if anything, maybe the opposite). Some people's tests on the Alexa do show a slight blooming around light sources like candle flames though I don't think the softening is as much as the lightest diffusion filter made... but you can use almost anything in the lightest strength if you want to get some blooming and softening -- 1/8 Black Frost for example. The real advantage to the Alexa is the dual-gain sensor which allows extended overexposure information so highlights roll off more gradually, plus their color science keeps color clipping down to a less obvious level so you don't get some odd color tinge in overexposed skin. If your GH4 or FS7 is producing images that are too sharp, I'd look at how they are being converted from log or raw because I suspect if you look at the original, it's not too sharp, the sharpening is being applied somewhere in the chain to a Rec.709 display image. 1 Link to comment Share on other sites More sharing options...
Joel Famularo Posted January 2, 2023 Share Posted January 2, 2023 I think based on conversations I've had with an Arri rep and articles like the one below, something like the Tiffen Digital Diffusion filter would help replicate the OLPF characteristics of the Alexa. https://gafpagear.com/the-new-mavo-lf-olpf-explained/ Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now