Baader ND 5 to 3.8

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Baader ND 5 to 3.8

Post by huwiler »

hello
if you don't want to wait until december:
the baader film nd 5.0 consists of a base film that is vapour-deposited on both sides. if you remove one side, as in my case with 'iron III cloride' 40%.
in a bath, the film has a permeability of exactly 3.8 after approx. 15-20 minutes. iron III cloride is corrosive, so please be careful and use it at your own risk.

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please note, if you want to try it yourself, only at your own risk, i do not guarantee that it is safe! and of course it can only be used with the camera, not visually!!!

martin
Last edited by huwiler on Tue Aug 09, 2022 2:25 pm, edited 1 time in total.


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Re: Baader ND 5 to 3.8

Post by GreatAttractor »

Interesting! So theoretically you could dealuminize some more (e.g., with one side completely gone, the film should have ND 2.5 - assuming both sides are initially coated the same). I'd be concerned about the polymer getting weakened mechanically by the solution, though.


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Re: Baader ND 5 to 3.8

Post by huwiler »

hy
i can't say at the moment to what extent the film is affected, at least visually there is nothing to see. i will test the film in the sun this week.
yes, you are right, the first layer on one side is gone, but there is still probably a copper layer, which also dampens. if you also remove the copper layer, the transmission would be even better and the exposure times even shorter.

martin


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Re: Baader ND 5 to 3.8

Post by marktownley »

Interesting indeed. Is it still usable after its bath?


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Re: Baader ND 5 to 3.8

Post by huwiler »

mark

yes it looks great, but i have to test it, let you know...

martin


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Re: Baader ND 5 to 3.8

Post by marktownley »

Silly question (maybe?) How do you only strip one side of the foil?


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Re: Baader ND 5 to 3.8

Post by huwiler »

hy marc

i put the film in a cardboard box with a lid and a rim about 2cm high and put the film on the side by these 2cm and fixed it with tape. you have to be careful that the surface of the film does not crease.

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Re: Baader ND 5 to 3.8

Post by marktownley »

Thanks Martin.


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Re: Baader ND 5 to 3.8

Post by huwiler »

hi

have tested the modified baader film nd 3.75 today
ar 13076, seeig not really for 24cm, 1.5-3.0" ,24cm maksutov zen, 2x zeiss barlow, blue filter 420/30nm, asi174mm. looks like the foil is ok!

martin

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please note, if you want to try it yourself, only at your own risk, i do not guarantee that it is safe! and of course it can only be used with the camera, not visually!!!


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Re: Baader ND 5 to 3.8

Post by Radon86 »

Interesting ! You are very brave to do this !

I thought ND3.8 was available but in an A4 size in some retailers (at least from a search in the UK), altough I have asked thme about stocks.

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Re: Baader ND 5 to 3.8

Post by Rusted »

The A4 size is far too limiting.
It would be better if the standard sheet was square.
30x30cm would cover the vast majority of potential users.


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