How many watt seconds do I need?

"me" wrote in message
...
"Tony" wrote in message
. com...
"Gregory Blank" wrote in message
...
In article , "me"

wrote:

How many watt seconds do I need? I'm using a 35mm film camera.
I'll be shooting in my single car basement/garage and a smallish
living
room. Ambient light from sun is dim, EV4 at 100 ISO for both.

I'd like 3 lights, main, fill and hair/bg/kicker. I assume the main
and
fill should be the same w/s but how many w/s should the other light
be? I'm trying to come up with a ratio like 1/2 or 1/4 as many w/s
as
main.

I also want more than 3 power levels. I think this would be more
versatile and may be a necessity since I don't have room to move
lights further from the subject to reduce power. What do you think?

I apologize if this question is vague but I have never purchased
studio lights before.
Thank you for your help.
me

A really nice feature, perhaps more important than ws is can you
independently adjust output to each of the heads. I have a 1200 ws
Power pack but can't independently adjust the lights, other than to
move them back or forward or use a louver inside the softbox.

1200 is good and strong for 100 asa. More is better if you can afford
it.

--
LF Website @ http://members.verizon.net/~gregoryblank

"To announce that there must be no criticism of the President,
or that we are to stand by the President, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."--Theodore Roosevelt, May 7, 1918

Start with a book on studio lighting. To begin with your assumption
that
main and fill should be equal is wrong.

I was referring to rated power not the ratio of main to fill.


Yes, but...

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill. Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

Yopu may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.



Peter

"Gregory Blank" wrote in message
...
In article ,
Randall Ainsworth wrote:

Jeez...you don't need to give 'em a sunburn. Shooting portraits of
ordinary people at f/16 is not advised.

In a lot of the churches I photograph in, old & dimly lit
Usually f/8 is barely possible with 100 asa for group shots, unless one
is using full power.

I was shooting in a church recently (the architecture, not a wedding, which
I don't do) and needed 3000Ws to get f8 on some of the shots. But that was
because for those shots I was filling daylight by bouncing the light from a
single head from high up off a wall.



Peter

On 12/12/04 9:32 pm, in article ,
"Bandicoot" wrote:

Yes, but...

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill.
Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

Yopu may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.

You advised that "infinite adjustability on every head" isn't needed - yet
if lights were of widely different output, as you also advise, it would
restrict flexibility. Surely cheap ND gels on a balanced set up is easier?

....oh, and there's nothing wrong with a 1:1 ratio.

Let's not cripple the poor guy! ;]

On 12/12/04 9:32 pm, in article ,
"Bandicoot" wrote:

Yes, but...

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill.
Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

Yopu may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.

You advised that "infinite adjustability on every head" isn't needed - yet
if lights were of widely different output, as you also advise, it would
restrict flexibility. Surely cheap ND gels on a balanced set up is easier?

....oh, and there's nothing wrong with a 1:1 ratio.

Let's not cripple the poor guy! ;]

"Bandicoot" wrote in message
...
"Gregory Blank" wrote in message
that
saidbe
In article ,
Randall Ainsworth wrote:

Jeez...you don't need to give 'em a sunburn. Shooting portraits of
ordinary people at f/16 is not advised.

In a lot of the churches I photograph in, old & dimly lit
Usually f/8 is barely possible with 100 asa for group shots, unless one
is using full power.

I was shooting in a church recently (the architecture, not a wedding,
which
I don't do) and needed 3000Ws to get f8 on some of the shots. But that
was
because for those shots I was filling daylight by bouncing the light from
a
single head from high up off a wall.



Peter


It could be said you can't have too much available power. How much you use
on any given shoot is up to you. Point re. having two or more same wattage
heads is in my opinion a good thing. From experience when one head is sent
for service you are not too inconvenienced as fill can be compensated for.
But the main is your, well, main light and the shoot often depends on
sufficient main light. I used 250's and 125's. For studio portraits 125's
are good and to have 4 or 5 of them in your kit is a good thing. I found
one had to wait for someone to die before I could locate good s/h ones.
250's on the other hand are easier to acquire. Excess power is easy to
dissipate but insufficient embraces larger stops with associated loss of
depth. The smaller lights need one to get them closer this will tend to
soften the light but can intimidate the customer if too close. If you come
across a biggy i.e. 1000 or 1200 and the price is right grab it. It will
prove invaluable when asked to shoot a bigger (darker) space.

I am assuming you are asking about monolights. For portables I'm silly
enough to get by with Metz ct60's very reliable.
--
Otzi

"Bandicoot" wrote in message
...
"Gregory Blank" wrote in message
that
saidbe
In article ,
Randall Ainsworth wrote:

Jeez...you don't need to give 'em a sunburn. Shooting portraits of
ordinary people at f/16 is not advised.

In a lot of the churches I photograph in, old & dimly lit
Usually f/8 is barely possible with 100 asa for group shots, unless one
is using full power.

I was shooting in a church recently (the architecture, not a wedding,
which
I don't do) and needed 3000Ws to get f8 on some of the shots. But that
was
because for those shots I was filling daylight by bouncing the light from
a
single head from high up off a wall.



Peter


It could be said you can't have too much available power. How much you use
on any given shoot is up to you. Point re. having two or more same wattage
heads is in my opinion a good thing. From experience when one head is sent
for service you are not too inconvenienced as fill can be compensated for.
But the main is your, well, main light and the shoot often depends on
sufficient main light. I used 250's and 125's. For studio portraits 125's
are good and to have 4 or 5 of them in your kit is a good thing. I found
one had to wait for someone to die before I could locate good s/h ones.
250's on the other hand are easier to acquire. Excess power is easy to
dissipate but insufficient embraces larger stops with associated loss of
depth. The smaller lights need one to get them closer this will tend to
soften the light but can intimidate the customer if too close. If you come
across a biggy i.e. 1000 or 1200 and the price is right grab it. It will
prove invaluable when asked to shoot a bigger (darker) space.

I am assuming you are asking about monolights. For portables I'm silly
enough to get by with Metz ct60's very reliable.
--
Otzi

Bandicoot wrote:

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill. Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

You may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.

Since you can't easilly predict the geometry of all your shots when you buy the
flashes and how far away fill, key and other lights may be, whether or not a
'brella or softbox is used, etc., you are better to have both a reserve in power
and stepless controllable power.

The power setting should ideally be a result of a chosen aperture, and not the
reverse. So again power margin and stepless control are required.

Purchassing lights to fit a minimum power requirement and having little control
is too constrictive. I should know... my two lights are 200 W-s and have only 1
step of control. I spend a lot of time moving lights around rhather than
controlling lights once they're in place.

Cheers,
Alan
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: there's no such thing as a FreeLunch.

Bandicoot wrote:

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill. Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

You may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.

Since you can't easilly predict the geometry of all your shots when you buy the
flashes and how far away fill, key and other lights may be, whether or not a
'brella or softbox is used, etc., you are better to have both a reserve in power
and stepless controllable power.

The power setting should ideally be a result of a chosen aperture, and not the
reverse. So again power margin and stepless control are required.

Purchassing lights to fit a minimum power requirement and having little control
is too constrictive. I should know... my two lights are 200 W-s and have only 1
step of control. I spend a lot of time moving lights around rhather than
controlling lights once they're in place.

Cheers,
Alan
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: there's no such thing as a FreeLunch.

Bandicoot wrote:

Because you don't want to end up with a 1:1 ratio, it is usually more
flexible if you don't start off with lights of the same power. In fact,
because you usually want your fill to be much softer than your main light,
it is usually _much_ more diffused, which can mean you need a more
powerful light than your main to start with, even to give you a 2 to 3 stop
lower resulting brightness at the subject. Alternatively you may use a fill
in a huge softbox quite close, and a main in a reflector a bit further
back - then it may be useful to have a lower powered fill. Few are the
ocassions where it is helpful to _start_ with them at the same power
though.

I'd think about getting lights where the lowest power setting on one came
down to around the highest on the other - then you can set them to the same
power when you really need to, but when - most of the time - you don't, you
have a much bigger total range of adjustment of the ratio between them than
if you start with two heads of equal power.

You may also save money by getting one of your heads with only a one or two
stop power range - you don't need infinite adjustability on every head, if
you set the less adjustable head first and then adjust the others in
relation to it.

Since you can't easilly predict the geometry of all your shots when you buy the
flashes and how far away fill, key and other lights may be, whether or not a
'brella or softbox is used, etc., you are better to have both a reserve in power
and stepless controllable power.

The power setting should ideally be a result of a chosen aperture, and not the
reverse. So again power margin and stepless control are required.

Purchassing lights to fit a minimum power requirement and having little control
is too constrictive. I should know... my two lights are 200 W-s and have only 1
step of control. I spend a lot of time moving lights around rhather than
controlling lights once they're in place.

Cheers,
Alan
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: there's no such thing as a FreeLunch.

"me" wrote in message:

What manufacturer's specification do you use when comparing?

I ran into the same frustrations when I decided to purchase lights.
I tried digging out guides number using a 7" 80-degree reflector,
but eventually I realized I was going to a bunch of work and not
getting any better data than w/s.

Part of the reason you're getting vastly different answers is
that you haven't really told us what you want to do with the
lights. For a single head-and-shoulder's shot Randall is
correct; any more than 50-100 w/s per light is not only wasted,
but may leave you with four awkward choices:
-- Stop down and gain DOF, potentially detracting from the shot.
-- Move the light away from the subject, giving harder light.
-- Adding ND filters, making it more difficult to focus.
-- Adding ND gels, which limits the use of certain modifiers.

Bandicoot is also correct. For larger subjects or on location, you
may find yourself wanting 1200 w/s per light.

For anything you can shoot in a one car garage and still position
your lights and camera, a pair of 160 w/s monolights and a small
"kicker" would probably suffice. That kicker could be another
monolight, an AC strobe, or even a slaved shoe mount unit.

A 160 w/s (or even a 320 w/s) unit frequently means a budget
model. All too many of these come with weak modelling lights,
limited power adjustments, poor build quality, or just inconsistent
output. Every time I use my lights, I regret buying too low-end a
set. For this reason, I recommend either upgradeable units like
the Alienbees B400 or medium-grade (at least) 320 w/s units
with at minium of a 4-stop power range.

--
Michael Benveniste --
Spam and UCE professionally evaluated for $419. Use this email
address only to submit mail for evaluation.