How to set exposure for split-neutral density filter?

Got a question I'm having trouble coming up with an answer for. Trying to
spend less time in Photoshop to fix picture exposure when shooting pics that
have a goodly amount of sky along with ground level detail I've seen
mentioned to use a split-neutral density filter on the camera lens. I know
there are different exposure levels (1 stop, 2 stop, etc.) available. What I
don't know is how to set the in-camera exposure meter. I use a Canon EOS 10D
and various lenses. Do I have to take the filter off each time to meter the
scene, do I have to carry a hand-held exposure meter? Or what? If I have to
do either of those, I might as well just take two exposures (one for the
sky, the second for all else) and do a composite in Photoshop.
--
de N2MPU Jack
Modeling the NYC/NYNH&H in HO and CP Rail/D&H in N
Proud NRA Life Member

Jack wrote:
: Got a question I'm having trouble coming up with an answer for. Trying
: to spend less time in Photoshop to fix picture exposure when shooting
: pics that have a goodly amount of sky along with ground level detail
: I've seen mentioned to use a split-neutral density filter on the camera
: lens. I know there are different exposure levels (1 stop, 2 stop, etc.)
: available. What I don't know is how to set the in-camera exposure
: meter. I use a Canon EOS 10D and various lenses. Do I have to take the
: filter off each time to meter the scene, do I have to carry a hand-held
: exposure meter? Or what? If I have to do either of those, I might as
: well just take two exposures (one for the sky, the second for all else)
: and do a composite in Photoshop.

There are several choices. First if you meter the image before puting the
filter on, and you position the edge of the split along the horizon, you
can set the camera for the metering you took of the main subject (spot
metering comes in very handy in this case). If your camera has the ability
to choose between several locations to meter on, you could set the meter
to read one of the points below the center point as the split would tend
to be across the center. Or if you can only center spot meter and you do
not wish to be puting the filter on and off, you might try practicing.
With some experience you may be able to predict what effect will be
resulting from half the metering spot being "shaded" by the split ND
filter.

One suggestion, you may want to look at the square format filters and
holders (such as the Cokin ones) instead of the round format ones. A round
format split filter will lock you into the split always being in the exact
same place on the image. But sometimes you may want to have only a sliver
of sky (like 1/3 of the total height) instead of the horizon having to be
across the center of the frame. A round filter is locked to a specific
proportion of the frame. Square ones can be slid in their holder, allowig
you to adjust the proportions of "shaded" to "unshaded". In addition you
can easily slip the filter just far enough away from the center to allow
the center spot meter to do its job without interferrence. And once you
have metered the subject you can then slide the filter into its proper
place if needed.

Randy

==========
Randy Berbaum
Champaign, IL

On 4/22/07 2:04 AM, in article , "Randy
Berbaum" wrote:

Jack wrote:
: Got a question I'm having trouble coming up with an answer for. Trying
: to spend less time in Photoshop to fix picture exposure when shooting
: pics that have a goodly amount of sky along with ground level detail
: I've seen mentioned to use a split-neutral density filter on the camera
: lens. I know there are different exposure levels (1 stop, 2 stop, etc.)
: available. What I don't know is how to set the in-camera exposure
: meter. I use a Canon EOS 10D and various lenses. Do I have to take the
: filter off each time to meter the scene, do I have to carry a hand-held
: exposure meter? Or what? If I have to do either of those, I might as
: well just take two exposures (one for the sky, the second for all else)
: and do a composite in Photoshop.

There are several choices. First if you meter the image before puting the
filter on, and you position the edge of the split along the horizon, you
can set the camera for the metering you took of the main subject (spot
metering comes in very handy in this case). If your camera has the ability
to choose between several locations to meter on, you could set the meter
to read one of the points below the center point as the split would tend
to be across the center. Or if you can only center spot meter and you do
not wish to be puting the filter on and off, you might try practicing.
With some experience you may be able to predict what effect will be
resulting from half the metering spot being "shaded" by the split ND
filter.

One suggestion, you may want to look at the square format filters and
holders (such as the Cokin ones) instead of the round format ones. A round
format split filter will lock you into the split always being in the exact
same place on the image. But sometimes you may want to have only a sliver
of sky (like 1/3 of the total height) instead of the horizon having to be
across the center of the frame. A round filter is locked to a specific
proportion of the frame. Square ones can be slid in their holder, allowig
you to adjust the proportions of "shaded" to "unshaded". In addition you
can easily slip the filter just far enough away from the center to allow
the center spot meter to do its job without interferrence. And once you
have metered the subject you can then slide the filter into its proper
place if needed.

Randy

==========
Randy Berbaum
Champaign, IL

Randy:
Thanks for the quick reply. I haven't yet placed my order with B&H, so I'm
not locked into a round versus square filter shape. I must admit I hadn't
thought of using A square filter. You answered a question that I never
considered: what to do about when the sky isn't 50% of the scene I want to
photograph. This is the one area where I miss the latitude of film
negatives.

My camera's metering only allows 3 metering: center weighted, center
weighted with averaging, and averaging. There's no apparent way to set a
particular metering point; there may well be, but I haven't found it yet. If
only camera operating systems software were as easy to muck about with and
customize as OSX (aka Unix) on a Mac is, then I'd write a routine to do what
I need.
--
de N2MPU Jack
Modeling the NYC/NYNH&H in HO and CP Rail/D&H in N
Proud NRA Life Member

Great reply - hadn't thought of the fixed circular filter issue.
Must have been why a pro photographer gave me a square Cokin filter about 20
years ago.
What is a good all round Cokin ND filter, seeing as there are so many ND
filters in their range.
regards
B



"Randy Berbaum" wrote in message
...
Jack wrote:
: Got a question I'm having trouble coming up with an answer for. Trying
: to spend less time in Photoshop to fix picture exposure when shooting
: pics that have a goodly amount of sky along with ground level detail
: I've seen mentioned to use a split-neutral density filter on the camera
: lens. I know there are different exposure levels (1 stop, 2 stop, etc.)
: available. What I don't know is how to set the in-camera exposure
: meter. I use a Canon EOS 10D and various lenses. Do I have to take the
: filter off each time to meter the scene, do I have to carry a hand-held
: exposure meter? Or what? If I have to do either of those, I might as
: well just take two exposures (one for the sky, the second for all else)
: and do a composite in Photoshop.

There are several choices. First if you meter the image before puting the
filter on, and you position the edge of the split along the horizon, you
can set the camera for the metering you took of the main subject (spot
metering comes in very handy in this case). If your camera has the ability
to choose between several locations to meter on, you could set the meter
to read one of the points below the center point as the split would tend
to be across the center. Or if you can only center spot meter and you do
not wish to be puting the filter on and off, you might try practicing.
With some experience you may be able to predict what effect will be
resulting from half the metering spot being "shaded" by the split ND
filter.

One suggestion, you may want to look at the square format filters and
holders (such as the Cokin ones) instead of the round format ones. A round
format split filter will lock you into the split always being in the exact
same place on the image. But sometimes you may want to have only a sliver
of sky (like 1/3 of the total height) instead of the horizon having to be
across the center of the frame. A round filter is locked to a specific
proportion of the frame. Square ones can be slid in their holder, allowig
you to adjust the proportions of "shaded" to "unshaded". In addition you
can easily slip the filter just far enough away from the center to allow
the center spot meter to do its job without interferrence. And once you
have metered the subject you can then slide the filter into its proper
place if needed.

Randy

==========
Randy Berbaum
Champaign, IL

Jack wrote:

: Randy:
: Thanks for the quick reply. I haven't yet placed my order with B&H, so I'm
: not locked into a round versus square filter shape. I must admit I hadn't
: thought of using A square filter. You answered a question that I never
: considered: what to do about when the sky isn't 50% of the scene I want to
: photograph. This is the one area where I miss the latitude of film
: negatives.

: My camera's metering only allows 3 metering: center weighted, center
: weighted with averaging, and averaging. There's no apparent way to set a
: particular metering point; there may well be, but I haven't found it yet. If
: only camera operating systems software were as easy to muck about with and
: customize as OSX (aka Unix) on a Mac is, then I'd write a routine to do what
: I need.

In the case of your camera's metering limits I have a slightly different
suggestion. First use a tripod and a square, split ND filter. If you
visualize your image as being composed of 9 squares (3 rows of 3 squares).
The majority of the metering (center weighted setting) will be this center
square. So since this setting will somewhat average the light intensity of
the whole image (with more importance being given to the center) metering
with the bright sky included will tend to be influenced by the bright sky.
So I would go ahead and put the split ND filter in place to darken the sky
and then let the meter do its thing including the filtered sky.

It would be a good idea to practice a bit as the result will be a slightly
more bright overall image and you may find that some slight compensation
will make the finished product more to your likeing.

BTW, for any filter that is not the same over the entire surface of the
filter, I find the flexability inherent in the square mount filters makes
a big difference. The filter can be slid a bit in the holder so the
effects can be shifted to the best compositional location. Of course this
is JMHO and everyone should make their own decisions.

Randy

==========
Randy Berbaum
Champaign, IL

Jack wrote:

Got a question I'm having trouble coming up with an answer for. Trying to
spend less time in Photoshop to fix picture exposure when shooting pics
that have a goodly amount of sky along with ground level detail I've seen
mentioned to use a split-neutral density filter on the camera lens. I know
there are different exposure levels (1 stop, 2 stop, etc.) available. What
I don't know is how to set the in-camera exposure meter. I use a Canon EOS
10D and various lenses. Do I have to take the filter off each time to
meter the scene, do I have to carry a hand-held exposure meter? Or what?
If I have to do either of those, I might as well just take two exposures
(one for the sky, the second for all else) and do a composite in
Photoshop.

Taking two exposures is probably easier and less cumbersome, plus you
get to second-guess the placement of the transition, which doesn't have
to be a straight line.

If you know how to meter for both of those exposures, then you already
know how to meter for an ND grad filter. The whole point of an ND grad
is to darken the sky so it'll 'fit' in the dynamic range of the
landscape's exposure.

--
http://www.xoverboard.com/cartoons/2..._argument.html

Jack wrote

What I don't know is how to set the in-camera exposure meter.

Use the camera's histogram feature to review your shot. Adjust
and reshoot if it shows overexposure.

Chris

"Benny" no spam wrote in message
...
Great reply - hadn't thought of the fixed circular filter issue.
Must have been why a pro photographer gave me a square Cokin filter about
20 years ago.
What is a good all round Cokin ND filter, seeing as there are so many ND
filters in their range.
regards
B



"Randy Berbaum" wrote in message
...
Jack wrote:
: Got a question I'm having trouble coming up with an answer for. Trying
: to spend less time in Photoshop to fix picture exposure when shooting
: pics that have a goodly amount of sky along with ground level detail
: I've seen mentioned to use a split-neutral density filter on the camera
: lens. I know there are different exposure levels (1 stop, 2 stop, etc.)
: available. What I don't know is how to set the in-camera exposure
: meter. I use a Canon EOS 10D and various lenses. Do I have to take the
: filter off each time to meter the scene, do I have to carry a hand-held
: exposure meter? Or what? If I have to do either of those, I might as
: well just take two exposures (one for the sky, the second for all else)
: and do a composite in Photoshop.

There are several choices. First if you meter the image before puting the
filter on, and you position the edge of the split along the horizon, you
can set the camera for the metering you took of the main subject (spot
metering comes in very handy in this case). If your camera has the
ability
to choose between several locations to meter on, you could set the meter
to read one of the points below the center point as the split would tend
to be across the center. Or if you can only center spot meter and you do
not wish to be puting the filter on and off, you might try practicing.
With some experience you may be able to predict what effect will be
resulting from half the metering spot being "shaded" by the split ND
filter.

One suggestion, you may want to look at the square format filters and
holders (such as the Cokin ones) instead of the round format ones. A
round
format split filter will lock you into the split always being in the
exact
same place on the image. But sometimes you may want to have only a sliver
of sky (like 1/3 of the total height) instead of the horizon having to be
across the center of the frame. A round filter is locked to a specific
proportion of the frame. Square ones can be slid in their holder, allowig
you to adjust the proportions of "shaded" to "unshaded". In addition you
can easily slip the filter just far enough away from the center to allow
the center spot meter to do its job without interferrence. And once you
have metered the subject you can then slide the filter into its proper
place if needed.

Randy

==========
Randy Berbaum
Champaign, IL

Jack

I had the 10D and the cokin pro series of filters etc. I found that using
the averaging metering with the filters in place does the trick. This goes
for when using two or three filters say when wishing to slow the shutter
speed down to blur a water fall or when shooting landscape and wishing to
bring up a sky using a graduated or split filter. Also, I cant remember
whether the 10D had exposure bracketing but if so using that is also a big
plus. I currently use a 20D and a 1 Dmk11n both with Cokin filters and have
never found exposure issues to be a problem with the evaluative metering.

regards
Don
"Jack" wrote in message
...
On 4/22/07 2:04 AM, in article ,
"Randy
Berbaum" wrote:

Jack wrote:
: Got a question I'm having trouble coming up with an answer for. Trying
: to spend less time in Photoshop to fix picture exposure when shooting
: pics that have a goodly amount of sky along with ground level detail
: I've seen mentioned to use a split-neutral density filter on the camera
: lens. I know there are different exposure levels (1 stop, 2 stop, etc.)
: available. What I don't know is how to set the in-camera exposure
: meter. I use a Canon EOS 10D and various lenses. Do I have to take the
: filter off each time to meter the scene, do I have to carry a hand-held
: exposure meter? Or what? If I have to do either of those, I might as
: well just take two exposures (one for the sky, the second for all else)
: and do a composite in Photoshop.

There are several choices. First if you meter the image before puting the
filter on, and you position the edge of the split along the horizon, you
can set the camera for the metering you took of the main subject (spot
metering comes in very handy in this case). If your camera has the
ability
to choose between several locations to meter on, you could set the meter
to read one of the points below the center point as the split would tend
to be across the center. Or if you can only center spot meter and you do
not wish to be puting the filter on and off, you might try practicing.
With some experience you may be able to predict what effect will be
resulting from half the metering spot being "shaded" by the split ND
filter.

One suggestion, you may want to look at the square format filters and
holders (such as the Cokin ones) instead of the round format ones. A
round
format split filter will lock you into the split always being in the
exact
same place on the image. But sometimes you may want to have only a sliver
of sky (like 1/3 of the total height) instead of the horizon having to be
across the center of the frame. A round filter is locked to a specific
proportion of the frame. Square ones can be slid in their holder, allowig
you to adjust the proportions of "shaded" to "unshaded". In addition you
can easily slip the filter just far enough away from the center to allow
the center spot meter to do its job without interferrence. And once you
have metered the subject you can then slide the filter into its proper
place if needed.

Randy

==========
Randy Berbaum
Champaign, IL

Randy:
Thanks for the quick reply. I haven't yet placed my order with B&H, so I'm
not locked into a round versus square filter shape. I must admit I hadn't
thought of using A square filter. You answered a question that I never
considered: what to do about when the sky isn't 50% of the scene I want to
photograph. This is the one area where I miss the latitude of film
negatives.

My camera's metering only allows 3 metering: center weighted, center
weighted with averaging, and averaging. There's no apparent way to set a
particular metering point; there may well be, but I haven't found it yet.
If
only camera operating systems software were as easy to muck about with and
customize as OSX (aka Unix) on a Mac is, then I'd write a routine to do
what
I need.
--
de N2MPU Jack
Modeling the NYC/NYNH&H in HO and CP Rail/D&H in N
Proud NRA Life Member