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View Full Version : All u need to know about using a 10 stop nd filter



David
10-07-2010, 10:06am
Hi Guys.

I recently caught the bug (ok maybe 9 months too late) for getting a black lens (10 stops) and exploring it since I have seen a few gr8 images lately using the ND400 or equivalent from B +W or Lee from people like Kane and JP on Flickr and others here so I ordered the B + W version and then went looking for tips on how to use it.

I came across this excellent, wonderfully detailed explanation with fantastic tips which you could apply to use of any ND or GND filter by an Aussie no less. It is well worth a look over even if you have been playing with NDs for ages.. the images themselves are inspiring. Here is the link.

http://www.redbubble.com/people/peterh111/journal/4421304-the-ultimate-easy-guide-to-neutral-density-filters

I @ M
10-07-2010, 12:05pm
I will bookmark that one for a lengthy read later, looks like some valuable stuff in there. :th3:

arthurking83
10-07-2010, 12:22pm
:confused:

sorry! He lost me when he said that using the black glass allows you to stop down(the lens) to f/22 or beyond! He also says that most DSLR's arent' as prone to diffraction as the 5DII is because they dont; have as many tightly packed pixels! HUH?

I stopped reading at that point! .... otherwise my head was about to explode with considerable pressure placed on it via the roundabout commentary.

David
10-07-2010, 3:28pm
:confused:

sorry! He lost me when he said that using the black glass allows you to stop down(the lens) to f/22 or beyond! He also says that most DSLR's arent' as prone to diffraction as the 5DII is because they dont; have as many tightly packed pixels! HUH?

I stopped reading at that point! .... otherwise my head was about to explode with considerable pressure placed on it via the roundabout commentary.

Might not be entirely accurate about everything he wrote Arthur but for people less experienced than you I thought there was some pretty good 'basics' information to take some value from.

arthurking83
10-07-2010, 5:49pm
I think my issue is that he's implying that by having the ability to shoot with a longer exposure time will create a better exposure!

Wrong! with digital it's the other way 'round. A shorter exposure time technically gives a better RAW in terms of signal to noise ratio. This is clearly evident with the fact that a long exposure requires the use of in camera LNR(long exposure NR).

In colder climates this may generally not be an issue, but if your camera is creating hot pixels or not effective in it's LNR ability(D70s) or if you get a phenomenon known as amp glow, they can al add up to ruin an image.

A ND filter will not help you get a better balanced exposure, whereas a CPL will, and a GND will.
An ND filter only slows down your shutter speed relative to what it would otherwise be for a given aperture and ISO value.(but that's being pedantic).

I'm not really having a go at him, although I think someone on Flickr should point out a few of the errors in his page.
Sometimes no info can be better than wrong info tho.
With no info at hand, you then go out and set on a course of discovery of your own testing and so forth.
With wrong info you wrongly assume that you're doing the right thing! :p

David
10-07-2010, 6:30pm
I think my issue is that he's implying that by having the ability to shoot with a longer exposure time will create a better exposure!

Wrong! with digital it's the other way 'round. A shorter exposure time technically gives a better RAW in terms of signal to noise ratio. This is clearly evident with the fact that a long exposure requires the use of in camera LNR(long exposure NR).

In colder climates this may generally not be an issue, but if your camera is creating hot pixels or not effective in it's LNR ability(D70s) or if you get a phenomenon known as amp glow, they can al add up to ruin an image.

A ND filter will not help you get a better balanced exposure, whereas a CPL will, and a GND will.
An ND filter only slows down your shutter speed relative to what it would otherwise be for a given aperture and ISO value.(but that's being pedantic).

I'm not really having a go at him, although I think someone on Flickr should point out a few of the errors in his page.
Sometimes no info can be better than wrong info tho.
With no info at hand, you then go out and set on a course of discovery of your own testing and so forth.
With wrong info you wrongly assume that you're doing the right thing! :p

Thanks Arthur: I always read what you have to say with keen interest and learn a lot from your input.

Xenedis
10-07-2010, 9:56pm
Wrong! with digital it's the other way 'round. A shorter exposure time technically gives a better RAW in terms of signal to noise ratio. This is clearly evident with the fact that a long exposure requires the use of in camera LNR(long exposure NR).

While a longer exposure will produce greater noise due to heat, I wouldn't necessarily agree that in-camera noise reduction is the solution.

I personally never use in-camera NR, as the camera takes a dark exposure which lasts the same amount of time as the original exposure, and then applies dark frame subtraction.

Noise reduction is something that can be done in post-processing by a far more powerful CPU than the one inside a camera, and I don't spend two hours taking a one-hour exposure.

arthurking83
10-07-2010, 11:13pm
Yeah you're right Xenedis. I never use in camera NR either, but I was referring to LNR(dark frame subtraction).
I don't know what Canon calls it but Nikon calls it Long exposure Noise Reduction(LNR :D) because that's what it is.. a form of noise reduction.

(from what I've read about it) apparently it's not the panacea, but it works well enough to be the best solution for now.
The Astro guys have the better solution in stacking frames of the same scene multiple times, as having RAW data with actual data(additional as opposed to reduction) is the better solution to noise problems.
That's difficult if not impossible to do in almost all landscape scenes due the more dynamic nature of landscapes.

In the old days(D70s for me), long exposures were not always entirely successful, so I'm weary of them in some ways. Of course modern cameras appear to be much better at it now(D300).

Xenedis
10-07-2010, 11:21pm
Yeah you're right Xenedis. I never use in camera NR either, but I was referring to LNR(dark frame subtraction). I don't know what Canon calls it but Nikon calls it Long exposure Noise Reduction(LNR :D) because that's what it is.. a form of noise reduction.

Canon calls it something very similar if not identical.

When I get a new camera, I specifically disable it (in the custom functions). I'm not sure what shutter speed the camera considers the threshold for engaging LNR, though.

I view my camera as a capture device rather than a processing device. :-)


(from what I've read about it) apparently it's not the panacea, but it works well enough to be the best solution for now.

I'd still recommend doing NR in post rather than in-camera. Battery life longevity is another reason for doing it on the computer instead.

ricktas
11-07-2010, 8:41am
This thread reminded me I was going to get one of these, ordered the Lee Big Stopper last night..

SnowA
11-07-2010, 10:11am
For the canon 30D my recollection is tha LNR kicks in for exposures longer than 1 second, if you have it turned on in the custom functions menu.

David
11-07-2010, 10:12am
This thread reminded me I was going to get one of these, ordered the Lee Big Stopper last night..

Good for u Rick; there is a few togs around that got all excited when Lee jumped on board and put out their Big Stopper: hope u get to post some results soon> PS Who do you get your Lee Filters from ?

ricktas
11-07-2010, 10:13am
www.vanbar.com.au in Melbourne.

Xenedis
11-07-2010, 10:20am
I bought my Lee filters from www.studiokitdirect.com in the UK.

At the time I bought my Lee 0.9 GND, 0.6 GND, filter holder and 82mm adapter ring, I paid around $350, which was $200 cheaper than what Vanbar wanted for the same items.

PindanRose
29-07-2010, 12:21pm
Thank you for this helpful info

DigiView
12-08-2010, 1:40pm
thanks for the info
I have the filter but havnt use it as yet

arthurking83
12-08-2010, 10:17pm
....



I'd still recommend doing NR in post rather than in-camera. Battery life longevity is another reason for doing it on the computer instead.

Bugger! .. I'd forgotten about this thread.

LNR is not like normal noise reduction. It's more a a noise cancelling or deleting routine that removes noise without affecting the quality of the image.

I don't know of any NR software that can remove noise non destructively.

The other option to not using LNR is to stack a series of multiple exposures, HDR style, but exposed the same way. Space Junkies use this method. Multiple short exposure bursts and then stacked.

if I get time over the weekend(my kids w/end), I'll post some extreme examples of how LNR can make a difference.

For exposures say up to about 5mins I reckon I can put up with not having an effective camera for the next 5mins, just for the sake of a teeny bit more image quality.

OlyE520
17-08-2010, 4:33pm
Thanks for the info

old dog
17-08-2010, 5:25pm
what a great review and expo on ND filters. thanks for the link David.