# Thread: New Tutorial: Neutral Density Filters & Long Exposures

1. ## New Tutorial: Neutral Density Filters & Long Exposures

This isn't yet public on the main site, but as usual, it's being posted here first:

Tutorial: Neutral Density Filters

It mentions some specific examples, and discusses all the common uses for these filters. There's also a section on using image averaging (aka "stacking") to effectively create a digital ND filter, along with its potential complications.

This article rounds out the series on camera lens filters. Polarizing, GND and ND filters are all now receive separate discussions.

As usual, please let me know if you feel anything is unclear, if you notice any typos, or just want to add something from your own experience.

Many thanks!

2. ## Re: New Tutorial: Neutral Density Filters & Long Exposures

Very timely, as I've just been lurking in the depths of the internet re of 10-stop Lee and B & W filters and the Singh-Ray Vari-ND. Looks like this is going to be the next purchase!

This is good, Sean. Very logical explanations. Easy to read. Couldn't see any obvious errors or omissions (which is always the cue for someone to come in behind pointing out what they are).

Only comment relates to the technical note and the use of "(since 1/23=1/8)". Will most people understand this formula? Would it be more simple to show it as a stepped-series?

3. ## Re: New Tutorial: Neutral Density Filters & Long Exposures

Only comment relates to the technical note and the use of "(since 1/23=1/8)". Will most people understand this formula? Would it be more simple to show it as a stepped-series?
I didn't know that.

I see you mean (1/2) cubed now.

4. ## Re: New Tutorial: Neutral Density Filters & Long Exposures

Originally Posted by Donald
Only comment relates to the technical note and the use of "(since 1/23=1/8)". Will most people understand this formula? Would it be more simple to show it as a stepped-series?
Thanks, it now reads: "since 1/2^3 = 1/(2*2*2) = 1/8"

5. ## Re: New Tutorial: Neutral Density Filters & Long Exposures

Thanks for the tutorial.
I have a question regarding filters. Does sticking in a ND or any other filter in front of the lens effect the IQ in anyway?. Is there a compromise?.
Thanks

6. ## Re: New Tutorial: Neutral Density Filters & Long Exposures

Hi Goparaju -- yes, anytime you place an extra layer of material between your sensor and the subject you have the potential to visibly reduce image quality. While this usually isn't a problem, filters which have smudges, micro abrasions or other defects can act to reduce sharpness and contrast. In general though, the benefit of being able to achieve a different look will outweigh any risk of lower technical quality. Just make sure to keep the filter clean and scratch-free.