Grad. ND Filters

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nikonuser

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Dave
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Just bought myself a set of Grad. ND Filters and would like to ask a pretty basic question please.
If I'm taking a landscape picture which has a very sunny sky and my setting without the filter are, say, ISO 200; f16; 1/125sec.
If I then put a ND2 grad filter on which reduces the highlighted sky would I need to increase the exposure by 1EV or does it depend which focus point you use?
I say this because if the filters effect is only down to the horizon and you are using the centre focus point this may be where the glass is clear so no EV is required, where as if the focus point falls within the grad effect then 1EV would be required.
thanks
Dave
 
Someone like Mark Mullen can give you more information, but no I wouldn't add extra EV.. just fit the filter and then compose/focus as you usually would.
 
Take an exposure reading from a mid tone area such as grass and note it down. Take an exposure reading from the sky (not the sun!) and work out the difference in stops from your mid tone reading. Insert the corresponding ND grad and expose for the mid tones.
 
Thanks Mark, and Bob could you clarify for me please......reading for mid tones then reading from sky, if the difference is say 3 stops then what do I do next please, as I did not understand you last bit exposé for the mid tones
Thanks
Dave
 
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Use a three stop grad.
 
This is what I used to do

I would spot meter the two different dark and bright areas using a slightly grey/off white area
Work out the difference in stops
Attach the required GND
Set up exposure for the darkest area
Take the shot

Now, understanding the lighting in a scene a bit better, 9 times out of 10 I can get away with this instead

Use evaluative metering, with the grad fitted, and metering for the final scene and take the shot without having to worry about metering twice.
 
nikonuser said:
Just bought myself a set of Grad. ND Filters and would like to ask a pretty basic question please.
If I'm taking a landscape picture which has a very sunny sky and my setting without the filter are, say, ISO 200; f16; 1/125sec.
If I then put a ND2 grad filter on which reduces the highlighted sky would I need to increase the exposure by 1EV or does it depend which focus point you use?
I say this because if the filters effect is only down to the horizon and you are using the centre focus point this may be where the glass is clear so no EV is required, where as if the focus point falls within the grad effect then 1EV would be required.
thanks
Dave
Click to expand...

The best way I found was to spot meter the foreground, spot meter the sky and see how many stops difference you have. I take one away from that figure as you would expect the sky to be brighter than the foreground, that gives you the strength of grad you need to balance the scene out.

EG if your 1/125th at f16 was for the foreground and for the sky you get 1/1000th at f16 then your difference is 3 stops (1/250th is one stop, 1/500th is two, 1/1000th is three), subtract one from that and use a 2 stop grad.

When using grads make sure you've got highlight warning on which will let you know if you've worked it out right. Also liveview is a godsend for using filters, you can use it to align the graduation line perfectly. If you've got a live histogram even better, you can make sure you're not clipping the highlights even before you take the shot.
 
Thats what I like for my feeble brain a fully detailed explanation....Many Thank Mark.
Really appreciate it being spelled out to me....I hope it will help others who want to know the same information.
Cheers
Dave
 
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