ND filters and extending exposure time help

[ShaneF]

I have started using ND filters lately and even with 12 stops of filters, F22 and ISO 200 I cant seem to get more the 1 second exposure time during the day. What am i missing here, how are people getting 2 minuets?

 

[NedM]

What kind of ND filters are you using? Lee?
Can you get a lower ISO?

What exactly are you taking a photo of? (Towards direct sunlight or away)
What are mode are you using? (Manual, bulb, etc?)

What kind of camera is it? And lens?

 

[480sparky38 37]

Assuming you're shooting in bright sun, the Sunny 16 rule gives you 1/100 sec, ISO 100 at f/16. If the best you can get at ISO 200 is 1 sec at f/22, you've only got 5-2/3 stops of ND. So my guess is you're ND filters are the number of stops advertised.

 

[D-B-J]

I've used a ten stop ND in BRIGHT sunlight @ f18 and shot for 150 seconds. Something is not as it appears...

Cheers!
Jake

 

[ShaneF]

Canon 650D , 24-70 2.8II
Shooting away from sun during mid day.
Shooting in manual
200 ISO is as low as i can go
cokin filters 2,4 and 8 ND filter
Trying to photograph a river

 

[480sparky38 37]

Canon 650D , 24-70 2.8II
Shooting away from sun during mid day.
Shooting in manual
200 ISO is as low as i can go
cokin filters 2,4 and 8 ND filter
Trying to photograph a river

Given you say you've got 14 stops of ND, your exposure should be 5:20.

Something just ain't jiving here.

 

[ShaneF]

yes i know none of this works out and that is why im asking for help to try to figure out why.

 

[480sparky38 37]

Are the filters 2, 4, and 8..........or 0.2, 0.4 and 0.8?

 

[D-B-J]

Canon 650D , 24-70 2.8II
Shooting away from sun during mid day.
Shooting in manual
200 ISO is as low as i can go
cokin filters 2,4 and 8 ND filter
Trying to photograph a river

Given you say you've got 14 stops of ND, your exposure should be 5:20.

Something just ain't jiving here.

No, Cokin's system seems to be different. According to a website I found, the 2 is 1 stop, the 4 is two stops, and the 8 is three. That adds to six stops. So your F22 original reading is probably around a 15th of a second. Reducing light by six stops would put you around 8 seconds.

Cheers!
Jake

 

[ShaneF]

it says on the box 2,4,8 and that all the information it really has. but your numbers make way more sense. 0.2 0.4 and 0.8

 

[D-B-J]

it says on the box 2,4,8 but your numbers make way more sense.

Filters for Photographic Lenses - Creative FIlters - www.cokin.co,.k

Give that a read.

The numbers do NOT, almost ever, directly correlate to "stopping" power. I.E., my Lee filters use 0.3, 0.6, and 0.9 to delineate each ND's strength (1, 2, and 3 stops, respectively).

 

[480sparky38 37]

No, Cokin's system seems to be different. According to a website I found, the 2 is 1 stop, the 4 is two stops, and the 8 is three. That adds to six stops. So your F22 original reading is probably around a 15th of a second. Reducing light by six stops would put you around 8 seconds.

Cheers!
Jake

Well, then, that would explain it. ND2 is 1 stop, ND 4 is 2 stops, ND 8 is 3 stops. 1+2+3=6.... not far from 5-2/3.

 

[ShaneF]

so it seems one again i have been fooled by my evil nemesis math and poor labeling.

D-B-J what site was it you were looking at listing at the cokin filters and specs? I would like to check it out thanks.

Thanks for helping me figure this out guys.

 

[D-B-J]

so it seems one again i have been fooled by my evil nemesis math and poor labeling.

D-B-J what site was it you were looking at listing at the cokin filters and specs? I would like to check it out thanks.

Thanks for helping me figure this out guys.

See my post above. There's a link to the Cokin site explaining their ND filters.

Cheers!
Jake