The GND thread!

[jacobsen1]

OK, I figured we could make a thread just to share shots taken with GNDs, and shots of GND setups to try to help people considering them see what they do, and how they do it. (I know I was confused before I got mine).

I took these today, specifically for a thread like this:

this is the lens side of my Cokin X-pro (their biggest size) holder, the black metal ring threads into your filter thread (that's a 77, so you can get a feel for how oversized it is). If you look carefully, you can see the top corners are clear and the bottom dark. This is a 121s which is their 3 stop soft. The brass wheel on the right (there's one under my thumb as well) can be tightened to prevent if from spinning around the 77mm adapter, I NEVER use this.... The glass you actually see in the center is my CP which mounts INTO the holder. It's a PITA to remove so it's actually never come out...


here's the view from the other side. Yes that's a dirty filter, but that's a big reason why I love the X pro size, you're only using a tiny portion... (truth be told I bought them to use with my 12-24, but sold it before using them). Here you can see the actual gradient of the filter and the whole CP (it snaps into the front), then the lens adapter in the back:


the X-pros are way more expensive, and they basically only come with cokin brand filters. Cokin is said to not be neutral, but supposedly they make the best holders. So a lot of people have cokin filter holders, but hi-tech filters (the best budget/quality ratio of the filters). I'll post some sample images in a bit...

[dansaa]

I thought you were going to post photos taken with the filters as well...?

[jacobsen1]

I thought you were going to post photos taken with the filters as well...?

I'll post some sample images in a bit...

damn woman, give me 10 minutes would you?

[dansaa]

damn woman, give me 10 minutes would you?

Ha ha ha! I totally didn't read that last line.

[jacobsen1]

OK, here's a perfect example. This was the first NSOP group meet I went to and everyone there had GNDs. I even owned my set, but had never used them yet, so I figured it was a perfect time to learn. Anyway, because I was new to them, I shot this first w/o:


then with:


NO OTHER DIFFERENCES, both are even processed with the same global adjustments, so that should give you some idea....

and another shot OF a GND from the gopro that morning:

[jacobsen1]

same in color: http://www.benjacobsen.com/wp-conten...9/img_3093.jpg

[jacobsen1]

#3.

[jacobsen1]

#4


#9

[jacobsen1]

#6


#7


#8

[jacobsen1]

123

[dansaa]

happy now?

[bleuquila]

oh hey.

So I got a 2-stop hard GND yesterday (which is not super useful here, what with there being no water ) And put it all together in the cokin z-pro holder and ... looking through the viewfinder I seriously cannot see where the line falls! Ssssoooooo ....

[jacobsen1]

yeah, with a soft edge filter it's not easy to see... watch the lightness/darkness of the frame as you slide it down. Basically, since I've shot them over the last few months, I can see it better now. But it's still very much a shoot and chimp affair for me.

[thomps6s]

oh hey.

So I got a 2-stop hard GND yesterday (which is not super useful here, what with there being no water ) And put it all together in the cokin z-pro holder and ... looking through the viewfinder I seriously cannot see where the line falls! Ssssoooooo ....

That is weird, you should be able to see the transition.

[bleuquila]

guess my eyes just need calibrated 0.<

[dansaa]

Press your DOF button? That helps sometimes.

[Reed Goodwin]

Wasn't there already a thread for this? I swear I've seen one...
Reed

EDIT: Yeah, this: http://www.newschoolofphotography.co...ad.php?t=13925

[jacobsen1]

[Colorblinded]

[astockwell]

Doesn't matter, I was going to maybe do a FAQ also. This works too. I'll put some of my stuff up later. I will have to take shots of my stuff tomorrow morning (Yes, I am going out before work again).

Andy

[astockwell]

If you want to see exposure times with what filters were used, click my smugmug link, and go to my "Best of" gallery.
-Andy

[jacobsen1]

this was a lame attempt at showing how the filters effect a shot using video mode....

[ame="http://www.youtube.com/watch?v=BDEjwRiTqOI&fmt=18"]YouTube - Newton Road[/ame]

[PhatheadWRX]

I need to find some landscapes. I have not even really used my GNDs yet

[thomps6s]

Hopefully when I find the Official Grad ND thread I can merge this with that thread, until then, check out the difference between Not using a grad ND filter and using a Grad ND filter.

A HiTech brand 3 stop Soft Edge Grad ND was used in the right half of this image. You can see that it has much more dynamic range and has saved the sky from blowing out and losing detail.



If shooting scenics/landscapes/etc... is something you enjoy doing, you should definitely buy at least one Grad ND filter.

I use Hi-Tech brand 4x5 (or Z-Pro) Grads. I have the following
3 Stop (0.9) Hard Edge Grad ND
3 Stop (0.9) Soft Edge Grad ND
2 stop (0.6) Soft Edge Grad ND

I can't remember what happened to my 2 stop Hard Edge, I either broke it or lost it at Stoney Point.

You can buy them at BH
www.bhphotovideo.com/c/search?Ntt=HiTech& N=0&Init...

Or you can get them from the Filter Connection. Their site sucks, but if you call they will help you out, they are very knowledgeable and friendly.
www.2filter.com/prices/Hitech/Hitech4x4.html

You can get P sized, however if you shoot full frame or shoot with any Ultra Wide or Wide Angle lenses, you will want the 4x5 (or Z-Pro) sized filters.

You can get a holder if you want, I hand hold all of mine so i can blend them better during the exposure.

Also, HiTech filters are truly Neutral so you don't get color casting. Cokin Grads can be had for less, but they are not neutral, they have a red cast.

If I were to own one Grad ND filter it would be a 2 stop soft edge or 3 stop soft edge. I find I use them more than anything else.

I hope this helps.

[jacobsen1]

nice, I have a shot from a few days ago showing how much a 1 stop can "save". It's pretty crazy once you start using grads the difference they make.

[jacobsen1]

bump!

[thomps6s]

Nice Find.

[thomps6s]

Mergified.

[jacobsen1]

here's another example:

that's with and without a 1-stop which makes a bigger difference than I give it credit for...

[thomps6s]

Yeah, that one stop did an awesome job.

[thomps6s]

Anyone know of a Cokin Z (4x5) knock-off holder? I have seen tons of P sized knock-offs, never Z's

[jacobsen1]

nope.

[astockwell]

Anyone know of a Cokin Z (4x5) knock-off holder? I have seen tons of P sized knock-offs, never Z's

Yeah, a Ebay and Google search yielded nothing by P size knock offs. The Cokin Z holder can be had for about $60, and is much cheaper than the Hi-Tech/Lee 4X5/4X4 size holders, and the Cokin works with the Lee and Hi-tech 4x4/4X5's. Not much other option though. They probably couldn't sell enough of them though. I suppose the P size is good enough for most photographers.

[astockwell]

Also, I did a big FAQ for the ND filter over at Dgrin, so if we would like that posted over here as new thread, and then we can merge that in also. Let me know.

-Andy

[thomps6s]

I owned the HiTech filter holder. It is cumbersome, bulky and over-priced by about $125

[jacobsen1]

Also, I did a big FAQ for the ND filter over at Dgrin, so if we would like that posted over here as new thread, and then we can merge that in also. Let me know.

-Andy

yes.

and I got my holder in the cokin grad kit originally (although I'm on Xs anyway).

[thomps6s]

This thread takes so long to load all of the images. There are a crap ton.

[thechickencow]

Yeah, I hate opening this thread.

Shawn, the cokin z sized holder makes a nice knock-off of itself. Its cheap, but gets the job done.

[thomps6s]

Yeah, I hate opening this thread.

Shawn, the cokin z sized holder makes a nice knock-off of itself. Its cheap, but gets the job done.

$60 isn't all that cheap plus you still have to buy the adapter ring.

[jacobsen1]

This thread takes so long to load all of the images. There are a crap ton.

I just edited out a bunch for you guys (it was wicked slow for me as well).

[astockwell]

I'll just post to this thread instead of starting a new one and merging it to this one anyway. So, about 6 months or so ago, I got bored and a wild hair and wrote a GND FAQ thread over at Digital Grin, because there were a lot of questions about them and filters in general, and little threads spread all over, that sometimes answered questions, and most times didn't. So just like my "epic" Water/Meth FAQ over at NASIOC, I decided to write an FAQ to put it all in one place.

A link to the entire thread over at Dgrin can be found here: http://www.dgrin.com/showthread.php?t=132827 So you can have a context and see the questions and discussion we have had over there about this.




Welcome, if you reading this, and are not sure what a Neutral Density (ND) Filter is or a Graduated Neutral Density (GND) filter is, read on, hopefully I'm going to answer all or most of your questions about this topic that since I have joined here there seems to be a lot of speculation and questions about, or people that are just unaware of a great tool in your bag. Also there seeems to be a lot of threads about them, but not one place where everything, or at least the basics in one place. In this FAQ, I will use links, and there will be stuff cut and pasted, and I may use some of my shots for examples. So if I have your interest piqued now, sit back, relax, and read on.

1. What is a Neutral Density Filter?

In photography and optics, a neutral density filter or ND filter is a "grey" filter. An ideal neutral density filter reduces light of all wavelengths or colors equally. The purpose of standard photographic neutral density filters is to allow the photographer greater flexibility to change the apeture or exposure time, allowing for more control, particularly in extreme circumstances.

A common example of this is use of a Graduated Neutral Density Filter to control sky exposure (hold back), while using enough shutter time to expose the foreground of a scene, and have a photo that has a balanced exposure, and looks as close to the human eye saw it as possible. As seen in this shot:



In that shot, stacked 2 and 3 stop GND Filters was used to bring the sky into dynamic range with the foreground that was approximately 5 stops darker. This allows the photographer to expose both sky and foreground equally.

Or a ND solid to reduce light, so shutter times can be longer, and produce a desired effect in a shot, example:



I don't remember what ND I had on for this shot, but it was taken in the middle of a mostly cloudy day, so I got the shutter time long enough to produce that silky/misty water effect in the shot.


2. What types of Neutral Density Filters are there?

The two most common types used in film and digital photography are:

• Round Screw-In filters that thread on to the front of a lens.
• The "Cokin" type system, which uses mostly square or rectangle filters, that are mounted to the lens via a holder, and a adapter ring that threads onto the lens.

3. What are the advantages and disadvatages to each type?

Round, Screw-In Filters:

Advantages:

• Compact, they usually take up less room in a kit bag, but it depends on lens size also, if you are using large ring size lenses, the filters can get pretty big.
• Ability to combine or stack filters on the front of a lens, although this can cause vignetting on some lenses, if using thick ring filters.
• Vari ND's or Combo ND/Polarizer filters, such as Singh-Ray brand produces
• Commonly sold at stores like Best Buy, Wal Mart, Ritz, etc, so they are easy to find in a pinch.
• A majority of ND's above 4 stops are sold in the Round/Screw-In style.

Disadvantages:

• In using Round/Screw-In Graduated ND filters, it give the photographer absolutely no control of the grad line placement in a scene, as the line is always in the center. (This is a big one for me)
• On certain lenses, UWA usually, round filters can vignette, as the angle of view is so wide on these lenses, that the ring that holds the filter element can be seen in the corners of a photo taken on the wide end of the lens.
• Some lower quality filters are not optically good, meaning they can cause color casts on photos taken
• If you have a lot of different lens sizes (front element size), you have to carry a set of filters for all lenses you wish to use the filters on (Another big one for me)

"Cokin" Style Filters:

Advantages:

• You can use them on any lens you carry as long as you carry the adapter rings for your particular system, which are usually cheaper than a round/screw-in ND filter usually costs.
• You have almost infinte possibilities for composing a shot, in relation to the grad line on a GND filter, since you can slide the filters up and down in the filter holder to control the placement of the grad line.
• As long as you buy the right system for the lenses you have, you shouldn't see vignetting on you lenses, example if you have a 10mm lens with a 77mm ring size, you might want to think of at least 100mm size filters or 4X4 or 4X6, or hand holding them if you buy 85mm or 3X3 filters
• Filters are typically made of resin, unless you spend mucho $$, so they are harder to damage, but are still able to be scratched or can chip if dropped on an edge on a hard or jagged object.
• More choices for types of ND and GND filters. Due to size, you can get reverse GND, which start darker in near the grad line, and get lighter as they move toward the edge, or you can get hardline or softline GNDs, which have many uses and advantages, which I will go into.

Disadvantages:

• Initial cost, some systems, depending on size and brand can be very pricey, but I typically think the cost of admission is worth it, but shop around, and find a system that works for you, and won't make you broke. Read a lot of reviews!!! But once you have a system of filters, and you have all the filters you want, all you need to do is buy adapter rings at that point if you get a new lens that has a different filter size than you already have.
• Depending on the amount of adapter rings, filters, holders, case, the system can get rather large. This can take up a bit of room in your kit. My recommendation is to buy a filter one at a time, if you find you use it, stick with it, and if you want more stops of ND, then buy another, the next level darker. Also read a lot about this before buying. If you have a bunch of filters in your bag you don't ever use, then it isn't worth wasting you money on them. Figure out what you shoot, and what filters would be best for what you typically shoot.
• They can scratch, they can chip, they can break. But this shouldn't be a discouragement from buying them. Just be careful with them, and you shouldn't have any problems.
• Dependent on what size lens you have, and FOV of the lens at wide end if a zoom, if you use the wrong size filters, you could also vignette, example is: My 16-50mm vignetted on the Cokin P series regular holder on the wide end, and it would sometime vignette on the P-Size wide angle holder if oriented incorrectly.

4. What brands are out there for purchase?


The answer is many.

Typical screw-in brands are Tiffen, Hoya, B+W, Singh Ray, Heliopan, and many more, but those are typically the better quality brands.

For "Cokin" type systems:

I am going to amplify this by saying when I use the word Cokin, I use it because it is the brand typically seen and used by a lot of people, but there are many makers of "slide holder" filter systems

They are:
Cokin, Lee, Formatt, Hi-Tech (made by Formatt), Tiffen, Schneider, are the common ones.

5. Where can I purchase both types?

Screw-In filters: Walmart, Target, Best Buy, etc. are the easy places the find them, but your selection will be limited here

B&H, Adorama, 2Filter.com, Filterhouse.com are going to have much more diverse inventories and types of filters, check here if you are looking for specialty stuff, or want a better selection, and if you don't see it on their site, it doesn't hurt to call and ask if someone makes something like what you are looking for. Example, Hi-tech makes 10 Stop ND filters, but 2Filter.com typically doesn't stock them, but they can be ordered off the Formatt.co.uk website.

For "slide holder" style systems, you can buy these at most of the places you can buy the round/screw in style at, but you are probably not going to find them at Best-Buy or Wal-Mart.

The end of part 1.

Part 2 on the next post

[astockwell]

Continued from Part 1

6. What Types of ND's do I need?

Only you can really answer this question, first ask yourself, what do you shoot the most, and what types of effects are you looking for when you use the filters. Are you trying to induce motion blur by using a longer shutter speed? Are you shooting seascapes or such that have a hard horizon line? Conversely is there any foreground items that a hard grad line would show up on if you placed it wrong, and make your picture look like someone drew a line through it? Do you want to do multi minute exposures during the middle of day, or early morning or late evening during the best light? Do you want to shoot shot with a lot of dynamic range and contrast, (sunrises and sunsets with good foreground interest), and have everything exposed right?

Here is what I will say, if you use a hard line grad in a scene without a good hard horizon line, or somewhere to logically terminate the grad line, your shots will look weird, as you will see this line run through your shot, and it isn't intended to be there, but it shows up either due to no straight line in the shot to put the grad line, or the filter you used is to dark for the scene. I use all soft line grads, as i can control how much ND I use by sliding up or down. Hard line grads tend to be not as graduated, as they are basically filter that is half dark, and half light with very little "taper"

Soft line grads are also easier to "hide" in a scene, and there is not hard dividing line.

I will also tell you what I currenly own, and have owned in the past, and what I use the most.

I currently have a set of Hi-Tech 4X4 and 4X6 filters, that fit nicely in to a Cokin Z-Pro holder, using Cokin Z-Pro adapter rings. I use the cokin holder since it is muc cheaper than the Hi-tech holder, and does the same thing.

If you ask me what I use the most I will tell you that with the photography subjects that I usually shoot, a 2 stop grad is usually what is on the front of my lens. Usually it is the right "darkness" for most scenes. That being said, I currently have 2 and 3 stop soft edge grads, and 1, 2, and 3 stop solids, and a 10 stop screw in, that I will screw my filter holder adapter ring into if I want to play around with really long exposure stuff. I have also noticed that lately during very wide dynamic range mornings (sunrises) I have been stacking 2 and 3 stop grads, and having some pretty good luck with them. You maybe have to do a grad layer in photoshop to pull the level up a bit where the grad was, as it can darken a bit too much, so you may have to pull it up to look right, but it can help control very bright skies a bit better than one ND. Allows more contrast control.

Bottom line, look at a lot of photos, read a lot of reviews, read a lot of forums, and if you can borrow some, do it, so you don't buy more than what you need to get started.

7. So why the 10-Stop filter?

For shots like this:


This is a 136 second shot, taken with a 3 stop solid ND, and a 3 stop GND. In the right conditions, imagine what can be done with a 10-Stop filter. The emphasis is on the cloud and water movement here. The extremely long shutter times give the clouds a chance to move through the shot, and the water becomes a mist with enough sea state. It also helps saturate the light in the sky a little more as the light has more time to change as the shot goes on, so you can get some pretty cool effects with ND filters, and this is my favorite aspect of what I do with them.

What sizes are common for "slide holder" system?

Common are 2X2 inch, 3X3", 4X4", 4x6" 2X3" 3x4" and 4x5"

Conversion time:

3X3 or 3 inch systems are relative to 85mm. (Cokin P Series)

4X4 and 4 inch systems are relative to 100mm. (Cokin Z-Pro Series)

If you get X-Pro by Cokin, well great, you have the biggest ones, and I don't think many others make filters this big, so I am not going to try to convert them.

I will tell you that on my Pentax 16-50mm lens, P-Series size vignetted using the Cokin regular holder, and sometimes with the wide angle holder, so food for thought if you think you are going to go cheap and get P-size, and use them on a UWA (Think Sigma 10-20) lens at the wide end and think they won't vignette, cause they will.

8. What is a reverse GND?

I mentioned this earlier, a reverse GND has the darker part of the gradient closer to the center, and it gets lighter going toward the "top" of the filter. I haven't used one yet, haven't needed one yet.

If someone has used one, and wants to chime in, and show examples, I will paste your experiences into this post.

9. What is this .6, .9, 1.2, business, and what does it mean?

ND filters are quantified by their optical density or equivalently their f-Stop reduction as follows:

Attenuation Factor| Filter Optical Density| F-Stop Reduction  | % Light Transmittance
2 	    	     0.3 		     1 		         50%
4 	    	     0.6 		     2 		         25%
8 	    	     0.9 		     3 		         12.5%
64 	    	     1.8 		     6 		         1.5625%
1,000 	    	     3.0 		     10 		 <0.1%
10,000 	    	     4.0 		     13		
1,000,000   	     6.0 		     20

So when you see ND-2, it is one stop of light reduction (refer to first column)

Also,
When you see .3, it is one stop of light reduction, refer to 2nd column.

So when you are deciding what filters you need, refer to this chart so you can see how much neutral density you want. It all depends on the desired effects you want to introduce into a shot, or if you think you may encounter a very contrasty scene, needing a lot of ND in the sky, to get the foreground exposed correctly.

I will continue to expand this as people point out new things I haven't covered yet, or their experiences, so if you guys see anything you want added to this, or otherwise, let me know. I hope this helps make a decision for people that are looking to cross this bridge. I will tell you this, I almost never shoot without these. I don't believe in adding gradient filters in post processing, and believe that filters are still a valuable tool to photographers who know how and when to use them, and I think they will never become obsolete. I agree a lot of things can be done in PS, but it still doesn't make up for good exposure made at point of capture.

You can read more by typing Neutral Density Filter into a google search, or here is the Wiki enty: http://en.wikipedia.org/wiki/Neutral_density_filter
Here is the Grad wiki:
http://en.wikipedia.org/wiki/Graduat...density_filter

Other threads concerning ND filters over at Dgrin where this post was originally published.

http://www.dgrin.com/showthread.php?t=115207
http://www.dgrin.com/showthread.php?t=117307
http://www.dgrin.com/showthread.php?t=112814
http://www.dgrin.com/showthread.php?t=107825
http://www.dgrin.com/showthread.php?t=94815
http://www.dgrin.com/showthread.php?t=91617
http://www.dgrin.com/showthread.php?t=68916







Also, I am by no means saying I know everything there is to know about this topic, and I am always learning, so if you have something to add, please add it. And Mods, consider stickying this, so people can easily find it, or put it into a threads of note thread.

One other thing you may want to consider is a tripod if you don't own one, as longer exposures require them to keep camera shake introduced by you the photographer out of the shot, and keep it sharp.

Refer to ian408's tripod thread:
http://www.dgrin.com/showthread.php?t=53477

Enjoy this,



-Andy

[astockwell]

Feel free to point out any inconsistencies, errors or questions you have about the above two posts.


Just noticed something, can someone format the code to make this table show up right?

Apparently the code from Dgrin didn't transfer over perfectly

Here is the data and the data columns

Attenuation Factor| Filter Optical Density| F-Stop Reduction | % Light Transmittance
2 | 0.3 | 1 | 50%
4 | 0.6 | 2 | 25%
8 | 0.9 | 3 | 12.5%
64 | 1.8 | 6 | 1.5625%
1,000 | 3.0 | 10 | <0.1%
10,000 | 4.0 | 13
1,000,000 | 6.0 | 20

[thomps6s]

Nice write up for sure.

[astockwell]

See my post above. If you have the means to do a formatted table, I would appericiate it if you could do it, and paste it in under Item #9, (What is all the .3, .9, and 1.2 business mean?)

[jacobsen1]

Attenuation Factor| Filter Optical Density| F-Stop Reduction  | % Light Transmittance
2 	    	     0.3 		     1 		         50%
4 	    	     0.6 		     2 		         25%
8 	    	     0.9 		     3 		         12.5%
64 	    	     1.8 		     6 		         1.5625%
1,000 	    	     3.0 		     10 		 <0.1%
10,000 	    	     4.0 		     13		
1,000,000   	     6.0 		     20

[thechickencow]

Great writeup Andy.

[astockwell]

Attenuation Factor| Filter Optical Density| F-Stop Reduction  | % Light Transmittance
2 	    	     0.3 		     1 		         50%
4 	    	     0.6 		     2 		         25%
8 	    	     0.9 		     3 		         12.5%
64 	    	     1.8 		     6 		         1.5625%
1,000 	    	     3.0 		     10 		 <0.1%
10,000 	    	     4.0 		     13		
1,000,000   	     6.0 		     20

[cartman]

sweeett

[/cartman]

[jacobsen1]

[cartman]

sweeett

[/cartman]

no problem. you can just use notepad/wordpad and tabs next time, then drop them between code tags.

[astockwell]

Ben,

I was thinking about this for a cover for the holder when using a ten stop. Cone shape, cut a hole in the narrow end, that goes over the lens, then you put the wide end which is already open over the filters and holder. Might have to sew it up a bit to make the fit right, but has potential. Also keeps us from having to go out and buy neoprene fabric.

http://www.westmarine.com/webapp/wcs...2&classNum=639