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View Full Version : Fader ND - a few questions



ade4all
03-15-2010, 01:47 PM
just a few questions about the fader nd people seem to be using - is it this one here by light craft? -

http://cgi.ebay.co.uk/Fader-ND-Filter-ND2-ND400-72mm-Neutral-Density-/130347707502

also can you also use the fader nd like a normal polarizer?
I've got a linear polarizer for my hmc151, was told you need circular for stills cameras - is that only for auto focus to work? seeing as for video i use manual focus would this polarizer work on the t2i?

after further investigation it seems the fader nd is a linear & a circular polarizer, so all i really need to do is buy a circular & fix it to my linear - is anyone able to confirm this? that way ive also got a circular polarizer for stills where i can use auto focus

Lee Wilson
03-15-2010, 03:53 PM
also can you also use the fader nd like a normal polarizer?

No, the reason being that the rear half will be in a fixed position (once screwed onto your lens) - you would need to be able to rotate the front element until the filter is as 'open' (bright) as possible- and then rotate both the front and the rear together as a unit (keeping the angular relationship between them the same) to set the polarisation - but as the rear element is fixed (to the lens) you cannot do this.

Hope that makes sense !

But . . . . if you buy two polarizing filters mount them in series - you can do exactly this, use it as a variable ND and still rotate the two together as a single unit to use as a polarizer as both polarizers have a rotating mount.

I made one of these and use it like this.


Setup: Rotate the front polarizer so that it lines up with the rear (where it is brightest).

1) Rotate the two together as a unit to set the polarization.

2) Rotate just the front element (while holding the rear in position) to set the ND amount.





I've got a linear polarizer for my hmc151, was told you need circular for stills cameras - is that only for auto focus to work? seeing as for video i use manual focus would this polarizer work on the t2i?

Yes and yes, the linear v circular thing is about scattering the light so that you don't cause the AF any problems, it is not an issue for video (where we tend not to use AF) and even with stills I haven't seen any real problems.


after further investigation it seems the fader nd is a linear & a circular polarizer, so all i really need to do is buy a circular & fix it to my linear - is anyone able to confirm this? that way ive also got a circular polarizer for stills where i can use auto focus


Yes, these variable NDs are really just a CP and a LP in series, it is (apparently) important in which order you place them in, if I remember correctly the liner is the front most element (but I would check that !)

ade4all
03-15-2010, 05:19 PM
thats great news, thanks Lee - though the linear I have was more expensive than the fader nd - its a b&w multi coated one - the equivalent circular one is double the price - do i need to spend to spend that much or will a cheap one do the trick - can you recommend a cheaper one, more in the 30, $50 range?

Lee Wilson
03-15-2010, 05:38 PM
thats great news, thanks Lee - though the linear I have was more expensive than the fader nd . . .

Which probably means the FaderNd™ is using a cheap(ish) LP.

Linear polarizers do tend to be expensive, maybe because they are comparatively rare (everyone wants CPs for the reasons you point out / AF) . . . LPs are said to be a more effective, higher quality polarizer than a CR


its a b&w multi coated one - the equivalent circular one is double the price

Normally I have found the linears are more expensive.



do i need to spend to spend that much or will a cheap one do the trick - can you recommend a cheaper one, more in the 30, $50 range?


The cheaper ones have to try really hard to be bad, especially when it comes to video (rather than stills), you end up paying for brand names often - but if you are going for 72mm (going on your link in your first post) things tend to get pricier.

I can't remember what I paid for each, I think my 77mm linear was around 50 (United Kingdom Squids)

ade4all
03-15-2010, 06:32 PM
thanks agin Lee, the circular does seem to be very expensive at that quality, as its mainly video I'll be using it for i might try a cheaper one, cant really justify 115 for b&w, Tiffen & Hoya do ones for 50, are they any good? & yes got 72mm cause of hmc151 & waiting for tamron 17-50 which is the same size

shaocaholica
03-15-2010, 08:13 PM
Err, couldn't you just take the half wave plate out of a CPL to make a LP? Actually, you can make your own 2 filter Fader ND by cannibalizing 2 CPLs if you're comfortable with taking them apart right?

vx1kOrnot
03-15-2010, 08:34 PM
I am using the one from Light Craft :)

http://vimeo.com/10087789

Lee Wilson
03-15-2010, 08:40 PM
Err, couldn't you just take the half wave plate out of a CPL to make a LP? Actually, you can make your own 2 filter Fader ND by cannibalizing 2 CPLs if you're comfortable with taking them apart right?

. . . or just buy a CP and a LP instead of two CPs + some DIY.

But if you have some spare (or access to some cheap) filters, then yes, you can make a good variable ND with a couple of CPs and a screwdriver.

gene_can_sing
03-16-2010, 08:18 AM
I have the Lightcraft one, and it works great. Very nice images. I got that one because Philip Bloom recommended it as being very good.

Get it, it saves you so much time unscrewing and carrying around NDs. Plus, it's so easy and fast to set the perfect exposure.

Mike McNeese
03-16-2010, 11:43 AM
Where the heck do you buy these things? I'm close to getting one, but thinking a matte box might make more sense for me since I'm using various sized lenses all the time.

rahn
03-16-2010, 11:47 AM
They sell it direct on eBay. Someone was selling one used here as well. I don't know if they still have it though.

smokecat20
03-16-2010, 12:53 PM
Where the heck do you buy these things? I'm close to getting one, but thinking a matte box might make more sense for me since I'm using various sized lenses all the time.

http://lmgtfy.com/?q=Fader+ND


Kidding aside, I got mines at www.lightcraftworkshop.com

They're located in Hong Kong, it takes about a week or two (depending on US customs) to deliver. So far it made sense for me to just buy 2 Fader NDs, 2 lenses with 58mm filter thread and another FaderND for my 77mm lens.

In terms of total time, for me and the types of shoots I do, it's easier to add and remove these filters, than it is to bring and assemble my mattebox. The only drawback to using these filters is it's nearly impossibly to add the lens hood.

gene