ND Filter 0.9... only 1/3rd of a second?

[gl600]

Hello,
I was trying to create an image that requires a long shutter speed so I went outside and composed the shot (mainly of the sky) and saw that my ND filter could only achieve 1/3rd of a second shutter speed. (note that this was the middle of the day, I was not looking into the sun.) I was looking to get a few seconds at least.
Here are the specifics of my equipment:
D60 with a Sigma 10-20mm lens.
Tiffen 77mm ND filter 0.9
f22 @iso 100.

With the filter, shutter speed= 1/3rd. Without the filter= 1/20.

Will I have to stack a bunch of these on the lens in order to get, lets say, a 15-20 second shutter speed?
How do people get those milky moving clouds?

Thanks in advance for the help!

 

[NateWagner]

well, it looks to me that the .9 is giving you about 3 stops of light reduction (so a .6 would give you 2 stops and a .3 1 stop)

I suppose if you stacked another .9 on there you'd be looking near the range you're wanting (probably in the 10 second range).

 

[UUilliam]

Ill base it on my 1/4

Without your filter you would probably be getting a shutter speed of 1/30 therefore the filter is doing its job perfectly!

as stated ^ 0.9 is 3 stops,if you stacked 1 more 0.9 onto it, you would get a 2 second exposure, if you place 3 on you should get a 15 second exposure etc..

 

[Overread]

Often things like milky moving clouds are going to be shot in the evening/early morning when the ambient lighting is far lower and thus you can use that far slower shutter speed. The longer shutter speed will make up for the lack of lighting so you can still get a bright shot at these times - with the blured cloud effect and without needing a lot of ND filters.
If you start trying to stack lots of filters you will cut down on light, but also image quality also as well as introducing other possible problems.
Don't try this middle of the day - instead wait and reshoot much earlier or later.

 

[NateWagner]

agreed, you could physically stack them, but it probably wouldn't be worth it aesthetically. As overread said, it would probably be a better idea to just take the pictures at a different time of the day.

 

[Dwig]

...
Will I have to stack a bunch of these on the lens in order to get, lets say, a 15-20 second shutter speed?
How do people get those milky moving clouds?...

They use stronger filters. To get what you want you need something in the 10 stop range. 10 stops = ND 3.00 = 1024x

 

[sA x sKy]

...
Will I have to stack a bunch of these on the lens in order to get, lets say, a 15-20 second shutter speed?
How do people get those milky moving clouds?...

They use stronger filters. To get what you want you need something in the 10 stop range. 10 stops = ND 3.00 = 1024x

Yeah 3.0's are needed. But good luck trying to get one. I have a 77mm B+W on order from Adorama since last Sunday and they still don't have it in stock.

 

[ranmyaku]

That's funny....I ordered one yesterday from B&H and I'm getting it in the mail tomorrow.

 

[sA x sKy]

That's funny....I ordered one yesterday from B&H and I'm getting it in the mail tomorrow.

That's kinda ironic. I got an email 2 days ago from the in-stock notification email signup that B&H had it in stock but when I went online yesterday to see if I could cancel my Adorama and get it from B&H instead, they were out of stock again.

Heh, maybe I'm just seeing things.

 

[gl600]

Ahhh, stronger filters. I didn't know that they had a stronger one. I bought the strongest that the store had. Is there any downside to using such a strong ND filter? Someone mentioned that you take a hit in quality??

 

[UUilliam]

B+W do the stronger filters, the downside is the cost...

The quality problem only really comes into play when you add more filters (they each become a new "front glass" and they also cause internal reflections sometimes (multi-coating helps to eliminte this)

 

[KmH]

Yeah 3.0's are needed. But good luck trying to get one. I have a 77mm B+W on order from Adorama since last Sunday and they still don't have it in stock.

Wow, ever since last Sunday? That's a really long time!

 

[henryp]

All our neutral density filter options are here. Fromthere you can use the menus to select size, density, etc.