Do you think it is a fake set of Lee Filters?

[GLS]

Seen the way they are printed, the lettering may easily change position towards the edge. But also a change in position could have been intended.
Here a Lee filter still in their plant.
View attachment 254525

Always possible. Maybe the extreme browning is too if the filter has been stored in very hot/humid conditions? Can't rule it out completely.

 

[itsdoable]

You are more likely to get fading if the filters were exposed to UV/Sunlight a lot. That's pretty typical with all organic dyes. And yellowing of plastic resins.

 

[cayenne]

You are more likely to get fading if the filters were exposed to UV/Sunlight a lot. That's pretty typical with all organic dyes. And yellowing of plastic resins.

So, would this be a selling point to go for real glass filter systems over the polymer ones like Lee?

C

 

[AgX]

So, would this be a selling point to go for real glass filter systems over the polymer ones like Lee?

What real glass filter? As I pointed out above there is practically no such non-organic glass grad filter alternative. (Though I welcome anyone who proves me wrong.)

 

[itsdoable]

Glass or poly-carbonate, most dyed through filters use an organic dye, which is subject to fading. Glass is more scratch resistant, but has a higher index of refraction, so it benefits from an anti-reflection coating.

It is possible to make a dyed through all glass graduated filter, but not economical ($$$).

Lee does make a thin film neutral density glass filter, which does not use organic dyes. The main reason is to avoid vignetting on wide lenses, as the oblique ray paths will travel through significantly more glass, and with a dyed through filter, those ray-paths would see more attenuation. I have not seen a thin film graduated ND filter yet, but they are possible, the same manufacturing techniques are used to make Canon's R series apodized element on the 85mm lens.

 

[GLS]

What real glass filter? As I pointed out above there is practically no such non-organic glass grad filter alternative. (Though I welcome anyone who proves me wrong.)

There are now a number of manufacturers making glass grad ND filters:

Formatt-Hitech's Firecrest Ultra range (https://formatt-hitechusa.com/colle...0x150mm-neutral-density-soft-edge-grad-filter)

Kase's Wolverine series (https://www.amazon.com/dp/B07GY1G33L)

Breakthrough's X4 series (https://breakthrough.photography/products/x4-gnd)

There are those Haida ones linked to earlier in the thread too. Maybe there are others as well. A common theme is they all have a pretty eye watering price.

 

[AgX]

These all are NOT glass filters in the true meaning of being minerally tinted glass in some way or another.

These all are laminates of an organic sheet with organic dyes between two glass panes.
Their only benefit is being much stronger against scratching and without risk of developing a hint after years in sunlight as maybe with those thick panes made from resin. The risk of light fading of their actual tinting still remains.

Making true glass coloured grads is costly and without chance of a soft edge, hardly an edge at all.
Making a true glass ND grad is possible, but I do not know any manufacturer that does so in sizes that interest us. And if the manufacturers of those grads above would do so for their ND grads, they would tell so. (I would be glad to be proven wrong on this.)

 

[GLS]

These all are laminates of an organic sheet with organic dyes between two glass panes.

I'm not sure that's true actually. I'm sure I remember reading somewhere that at least one of these used metal oxide depositing on the inside of the laminate to create the ND part, but I can't find the info now.

 

[AgX]

Exactly that is the technology I am hinting at (gradient metallic depostion on the glass surface). But so far I know grads with such metallic coatings only from scientific filters.

If one could apply such gradient application technology also to dichroic filters one could make non-organic colour grads in similar way too.
But I have not seen such at all.

 

[Arturo Carmona]

These all are NOT glass filters in the true meaning of being minerally tinted glass in some way or another.

These all are laminates of an organic sheet with organic dyes between two glass panes.
Their only benefit is being much stronger against scratching and without risk of developing a hint after years in sunlight as maybe with those thick panes made from resin. The risk of light fading of their actual tinting still remains.

Making true glass coloured grads is costly and without chance of a soft edge, hardly an edge at all.
Making a true glass ND grad is possible, but I do not know any manufacturer that does so in sizes that interest us. And if the manufacturers of those grads above would do so for their ND grads, they would tell so. (I would be glad to be proven wrong on this.)

Well I would say that filters used in cinematography are full glass tinted ones, tiffen is the most common brand on that. Beyond that, Lee filters has this video in which they show the manufacturing process and they say the filters are dyed by hand (min.0.40).

 

[AgX]

I

Well I would say that filters used in cinematography are full glass tinted ones

This thread is about gradient filters, be they a ND gradient , a colour gradient or a ND gradient over a uniform tint. And only on these I commented concerning glass.

 

[barzune]

There are no gradient filters in minerally coloured glass, .....

Wow ! Are you sure?

 

[Arturo Carmona]

I


This thread is about gradient filters, be they a ND gradient , a colour gradient or a ND gradient over a uniform tint. And only on these I commented concerning glass.

Of course in cinematography we also use Gradient ND filters and for that reason I mentioned that, but I am not sure the exact process of manufacturing it. What I have found interesting is the next thing on this type of Tiffen Nd´s about its brownish tones, altought I dont mean that is my case.

These filters have a unique bronzed look to them which comes from the dual-layer ND element. Because one of the elements is designed to reflect away IR light, the filters appear to have this brownish-red color. In fact, that color will have no impact on the image as it is being reflected away before the light can pass through and reach the lens. So far, this is the only way to assure that an ND will create a clear, neutral image and last for years and years.

https://tiffen.com/pages/natural-nd-edu

 

[AgX]

Metal-coated filters yield extra reflection by that layer, that could be an explanation.