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canoli
07-30-2009, 03:23 PM
Hey All -


wondering if you can help me choose a ND filter...I'll be out in Big Sur next month, and the coast is generally very sunny once the fog burns off. I've never used a ND filter, so anything you can tell me will be helpful.


I'll be using a 40D and the 17-40, 70-200 2.8 IS and the 50 1.4. I have a good tripod, cable release.


I'm leaning toward the square filters with a 2-stop factor. But do I need a holder as well, or do you generally just hand-hold the filter in front of the lens?


I've researched the B+W threaded filters, and they look fine. But a square filter offers much more freedom in terms of placing the filter, right?


I use high-quality filters when I use them at all - I only own B+W MRCs so far - so I'm used to spending $100 - $200. But $200 is my limit.


Any ideas? I do own a good polarizer already, but I think I'm going to need more light-stopping power than it provides.


Thank you guys! I appreciate it...

Bob
07-30-2009, 03:46 PM
If you have a polarizer why do you think you will need a ND filter?

Sean Setters
07-30-2009, 03:50 PM
It is a good question as to why you believe you'll need it, but...


If you simply want an ND filter, then a screw-on will work just fine. However, if you want a graduated ND, then the square filters are the way to go.

T Bigger
07-30-2009, 03:53 PM
For the ND grad I use a Cokin P holder with 2 & 3 stop grad filter. I use HoyaPro 1 round threadedND filters 2 & 3 stops. The square


filters work great at sunrise & sunset you can adjust for the horizon better.


Here is link to check out.


http://www.2filter.com/index.htm ("http://www.2filter.com/index.htm)

canoli
07-30-2009, 04:44 PM
Thanks for the replies guys.


The way I understand it right now, ND filters give much more light-stopping power (depending on which one of course) over CPs.


The CP I own cuts reflections the way it's supposed to, but as far as evening out a high-contrast landscape, its power is pretty limited.


It's a B+W - http://www.bhphotovideo.com/c/product/9777-REG/B_W_66044843_72mm_Circular_Polarizer_Multi_Resista nt.html ("http://www.bhphotovideo.com/c/product/9777-REG/B_W_66044843_72mm_Circular_Polarizer_Multi_Resista nt.html) which I use with a step ring on the 77mm glass.


I'm picturing the Big Sur coast, with the big beautiful rocks in the water, seals sunning themselves, isolated lagoons, etc., all under a bright midday sun. Of course I'll be out at sunrise and sunset as well, but generally the fog is heavy until 9 or 10am every day.


Can you use the Cokins w/out a holder? Is that the way people use ND filters, just hand-hold them? I think I want a Graduated ND with a soft transition, though I guess a hard transition would suit me better along the coast. I figured the soft will work better where I normally shoot, in and around NYC.


Is the Cokin system expensive? I haven't researched their stuff yet...

canoli
07-30-2009, 04:55 PM
Thank you for the link T -


this might be exactly what I'm looking for...


http://www.2filter.com/prices/htpackages.html ("http://www.2filter.com/prices/htpackages.html)


It's a great price - but am I missing something important? I figure I'll buy the 77mm Soft-Edge and have everything I need...yes?

Alan
07-30-2009, 05:16 PM
Can you use the Cokins w/out a holder? Is that the way people use ND filters, just hand-hold them? I think I want a Graduated ND with a soft transition, though I guess a hard transition would suit me better along the coast. I figured the soft will work better where I normally shoot, in and around NYC.


Is the Cokin system expensive? I haven't researched their stuff yet...
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I have the Cokin set up and you'll definitely want a holder for it. I wouldn't recommend trying to hand hold it. With the holder, you can move the filter up and down, to find the right spot, especially for sunrises/sunsets.


No, they're not expensive.


The holder allows you to turn it so that if you run into a situation (like a slanted landscape...mountain ridge, for example), you can have your ND line up with the demarcation.


Get the holder. Well worth it.


Be sure to wipe those filters off well before you use them, too.

T Bigger
07-30-2009, 05:35 PM
That is what I bought. The soft edge are what work best for my use.

canoli
07-30-2009, 05:44 PM
Thanks Alan - I'm going to buy one now from the website T Bigger posted.


I spoke with a guy there - John - and he was very knowledgeable, friendly, etc. He said the same thing you did - get the holder, it's cheap and well worth it.


If you ever need to "talk filters," call 2filter.com and ask for John, 1-800-882-2832. He knows his stuff and is very helpful.


Thanks for the replies everyone, and thanks for the link to http://www.2filter.com/ ("http://www.2filter.com/)

peety3
07-31-2009, 11:44 AM
wondering if you can help me choose a ND filter...I'll be out in Big Sur next month, and the coast is generally very sunny once the fog burns off. I've never used a ND filter, so anything you can tell me will be helpful.


I'll be using a 40D and the 17-40, 70-200 2.8 IS and the 50 1.4. I have a good tripod, cable release.


I'm leaning toward the square filters with a 2-stop factor. But do I need a holder as well, or do you generally just hand-hold the filter in front of the lens?





Do you have any sample pictures (with EXIF) that'll represent what you're trying to accomplish? For example:


f/22, ISO 50, 1/15th:


http://photos.templin.org/albums/pj-baptism-party/426C0261.sized.jpg


I had the 85/1.2 with me, and tried some shots with it, but I had no ability to get thin DoF at the same time as motion blur - I think wide open I was getting 1/5000th at ISO 100 (if not ISO 50).


If I wanted f/1.2, ISO 50, 1/8th, I'd have needed 8 stops of aperture change and one stop of shutter change, so I'd need a 9-stop filter to get those specs. I'd probably end up with a 10-stop filter and ISO 100 (which I wouldn't be complaining about) to get there.


You might want slow water/surf blurs, so you may not care about thin DoF (but might want to get closer to f/11 to avoid diffraction effects, so that's two stops). You'll want to confirm the minimum aperture of your lens (i.e. the 85/1.2 only goes down to f/16, whereas I think I have a lens that'll go to f/32). You'll want to determine the shutter speed you want, and work the math from there.


I haven't bought ND filters yet, as I don't feel like I have the disposable cash to buy a full set, and rarely have a strong desire to have one. That said, I figure I'll get something along the lines of 1, 2, 4, and 8 stops, knowing that I can stack no more than one filter and get most combinations from 1 to 12 stops (I'd be missing 7 and 11 stops, oh well). Given normal product lines, I suspect I'll be looking at the 1, 2, 3, 6, and 10-stop models, which would give me everything from 1 to 16 stops (except for 14 and 15 stops) with no more than 2 filters at a time.

shutr
08-04-2009, 09:53 AM
Have you noticed any loss in picture quality such as in the fine details when useing these Cokin filters?


Thanks Bruce