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Author Topic: How much light(watts) do you need to shoot f8 to f11 in studio  (Read 7304 times)

Dylan777

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I plan to buy a Studio strobe lighting set.

Here is my plan:
1. Setup location, my garage
2. Shooting F-stops, min f8 prefer f11
3. Shutter speed, 1/125 or faster
4. 100ISO
5. Budget $300 to $600 (lower better, don't plan to use much)

You guys know the min light(watts) I should be looking for? or any good suggestions?

Thanks
Dylan
« Last Edit: April 06, 2013, 12:25:07 PM by Dylan777 »
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Roger Jones

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #1 on: April 06, 2013, 12:39:46 PM »
It depends on how large your subjects are, how far they will be from the lights and what type of modifiers you will be using. Its better to spend a little more when you make your initial investment rather than find that you can't do something you want to do later because you under spec'd your gear. Studio strobes are aspirational gear in that many people buy them and find that they don't really use them much so you can often find like new gear on ebay/craigs list for 20-40% less then new retail. I'd recommend starting with a couple of monolights such as Alien Bees AB 800s combined with ebay soft boxes or umbrellas. You will also need to budget stands, reflectors and perhaps a backdrop.

TrumpetPower!

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #2 on: April 06, 2013, 12:53:05 PM »
What you want is a couple B800s. But if you can spring the extra $80 / head for the B1600s, you won't regret it.

Cheers,

b&

redelses

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #3 on: April 06, 2013, 01:25:18 PM »
i've been using the alien bees b800 (320 W/s) for studio portraits. typically with the ab800 set at 1/16 (20 W/s) power with large softbox, and at f2.8-4.0 iso 100 shutter 1/200, i get great lighting. complementing the ab800 with canon 430ex ii (also around 1/8 to 1/16 power), i easily get to f8. with the ab800 at full power, it's usually too much light indoors for portraits.

Lawliet

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #4 on: April 06, 2013, 01:39:08 PM »

You guys know the min light(watts) I should be looking for? or any good suggestions?


At 2m with a rect. softbox in the 2'x3' to 4'x6' range I need about 150Ws to get f/11; a bit more with very narrow boxes or grids. With a white BD you're in the same ballpark. If you're in a confined space without black light absorbers the walls will act as fill cards, giving you more, although uncontrolled, illumination.
Keep in mind that you might want to dial light down, either to fill in shadows or to shoot wider open or with inherently more efficient tools. Thats where to much power and a narrow range is a problem.
(From a european perspective the elinchrome RX one or renewed D-lite2 are an interesting entry level offering. Enough power for indoor use, a clean accessory/upgrade path and they can be remote controlled via iPhone or PC - at a price point compareable to chinese imports.)

RLPhoto

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #5 on: April 06, 2013, 02:39:19 PM »
For the large modifiers I use atleast 300w/s. A pair of AB800s should do a lot.

neuroanatomist

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #6 on: April 06, 2013, 03:27:44 PM »
What you want is a couple B800s. But if you can spring the extra $80 / head for the B1600s, you won't regret it.

Are you sure?  The B1600 has a 640 Ws max like the Einstein, but only a 6-stop (vs. the Einstein's 9-stop) range. The max power is great for overpowering the sun outdoors, but in a small indoor space like the OP is talking about, depending on modifiers used, the min power of the B1600 may be too much.  I often need to dial my Einstein down by 7-8 stops indoors (lower than the B1600 can be set). 

Another option is B1600s plus a 2- or 3-stop ND (assuming one doesn't want to stop down past f/22).
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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #6 on: April 06, 2013, 03:27:44 PM »

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #7 on: April 06, 2013, 03:32:23 PM »
I went for the  Einstein's more money but a lot more useful  !

TrumpetPower!

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #8 on: April 06, 2013, 03:47:16 PM »
What you want is a couple B800s. But if you can spring the extra $80 / head for the B1600s, you won't regret it.

Are you sure?  The B1600 has a 640 Ws max like the Einstein, but only a 6-stop (vs. the Einstein's 9-stop range). The max power is great for overpowering the sun outdoors, but in a small indoor space like the OP is talking about, depending on modifiers used, the min power of the B1600 may be too much.  I often need to dial my Einstein down by 7-8 stops indoors. 

Another option is B1600s plus a 2- or 3-stop ND (assuming one doesn't want to stop down to f/22).

Well, even with the B1600s, I've gone close to minimum power but never actually wished I could cut it further. And I do frequently use my Einsteins at or near full power when I'm using them to light a seamless white background so as to blow it out. And I generally shoot at f/8, sometimes f/11.

I suppose there might be setups where they're too much, and I suppose there might be styles where such setups are common...but they're rather different from mine.

But, of course, the Einsteins are awesome.

(Sadly, there was an incident late yesterday afternoon...a stand tipped and one of the un-modified Einstein fell flat on the Pyrex cover. It'll need to meet its maker for resurrection, but I'm sure I'll be out of pocket well under $100, and that'll include the loaner. PCB service is awesome -- it's worth buying their gear just for how well they take care of you!)

Cheers,

b&

Dylan777

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #9 on: April 07, 2013, 11:40:05 AM »
Thanks everyone for helping so far.

I'm still haven't pin-point which strobe light  set yet....STILL LOOKING :-\
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Mt Spokane Photography

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #10 on: April 07, 2013, 11:47:22 AM »
Lumens, not watts!  Efficiency of different lighting types is hugely different.  You might need 1500 watts with a incandescent setup but only 400 watts with a efficient LED light setup.
Of course, the wattage needed depends on distance and size of the lighted area.

Lawliet

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #11 on: April 07, 2013, 12:03:22 PM »
Lumens, not watts! 

To get an exposure you need lms/m2, lumen-seconds/square meter. Good thing: flashtubes have about 40lm/w and a flash duration shorter then the sync time, so all strobes set to say 100Ws produce the same 4000lms, about the same as four 30W CFLs in one second (or a 650W halogen during a 1/5s exposure)

neuroanatomist

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #12 on: April 07, 2013, 02:39:46 PM »

Dylan777

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Re: How much light(watts) do you need to shoot f8 to f11 in studio
« Reply #14 on: April 25, 2013, 07:56:45 PM »