Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: Joe Towner on October 31, 2013, 02:26:53 pm

Title: How much strobe power is 'enough'?
Post by: Joe Towner on October 31, 2013, 02:26:53 pm
I am new to shooting a Hasselblad H4D-50, and need to light 6-8 folks.  I'm going back and forth on how much strobe power I want, having used the Bowens 400w/s kit and a pair of Profoto AcuteB 600w/s.  Based off my experience so far I feel like I need to go to a higher w/s power level, but how high?  I am considering the Einstein's (yes, I'm in the USA) but fear the 640w/s would be too limiting.

As for modifiers, I would be getting a beauty dish, a large octobox, and a couple of umbrellas.  My fear is that I'll be running at max power when shooting more than a few people, and being limited in what modifiers I can use.  Toss in that I want to be mobile, so what ever power level I go with, I need the ability to go to battery as well.  Am I over thinking this?

Thanks in advance.
Title: Re: How much strobe power is 'enough'?
Post by: photo570 on October 31, 2013, 02:38:51 pm
Hi Joe,

You can never have too much power! MuuuHaaaahaaa!!

I have 32700ws of flash units, and still growing. I think I may be a gear addict as well. I wonder if Michael and Kevin have considered starting a support group.  :D

Kind regards,
Jason Berge.
Title: Re: How much strobe power is 'enough'?
Post by: TMARK on October 31, 2013, 02:51:41 pm
As much as you can get.  Just make it modular so if you need to rent more light it all goes together with your modifiers.

Higher ISO helps, like a clean 800, cuts your need for w/s.
Title: Re: How much strobe power is 'enough'?
Post by: Ken R on October 31, 2013, 02:53:23 pm
I am new to shooting a Hasselblad H4D-50, and need to light 6-8 folks.  I'm going back and forth on how much strobe power I want, having used the Bowens 400w/s kit and a pair of Profoto AcuteB 600w/s.  Based off my experience so far I feel like I need to go to a higher w/s power level, but how high?  I am considering the Einstein's (yes, I'm in the USA) but fear the 640w/s would be too limiting.

As for modifiers, I would be getting a beauty dish, a large octobox, and a couple of umbrellas.  My fear is that I'll be running at max power when shooting more than a few people, and being limited in what modifiers I can use.  Toss in that I want to be mobile, so what ever power level I go with, I need the ability to go to battery as well.  Am I over thinking this?

Thanks in advance.

Given that a LOT depends on your style, the particular modifiers you use (output varies between brands and interior diffusion panels and interior coatings), how you use them, the location you use them in and obviously preferred camera settings, generally you want at least 2400 w/s if mainly working at iso 50 and 100 and f8-f11 for a basic three light setup. I usually take 2 profoto 1200 packs and 4 heads minimum. Most likely for a job like the one you describe I would take 3 1200 packs and 6 heads.
Title: Re: How much strobe power is 'enough'?
Post by: TMARK on October 31, 2013, 02:59:09 pm
Ken speaks the truth. 

When I was shooting editorial portraits I usually brought 2 Acute2 1200 packs and four heads.  This was for location because the Acutes draw less power than the Pro7 packs, meaning less risk of blowing the crappy single phase power in many older apartments.  I could use a P30+ at 100, 200, and 400 with good results, between f8 and f11.  Chimera medium shallow banks for fill, maybe a Mola Demi with a grid for key, or a Magnum.

Given that a LOT depends on your style, the particular modifiers you use (output varies between brands and interior diffusion panels and interior coatings), how you use them, the location you use them in and obviously preferred camera settings, generally you want at least 2400 w/s if mainly working at iso 50 and 100 and f8-f11 for a basic three light setup. I usually take 2 profoto 1200 packs and 4 heads minimum.
Title: Re: How much strobe power is 'enough'?
Post by: JoeKitchen on October 31, 2013, 03:06:14 pm
I agree, you can never have enough power.  I use Profoto Acutes and usually pack 3600 w/s, but will rent more.  (I also use a lot of tungsten lighting.)  I am in agreement that you should buy something that will also be easy to rent, since it will cut down on what you have to buy in terms of additional power and modifiers.  

In terms of brand though, I would recommend going with a company that has a track record of producing great stuff.  I have no experience with Einsteins, but I have heard they crack.  I also heard they have a great warranty, but no client is going to care about that after hearing the shoot is cancelled.  I travel all the time and beat the hell out of my equipment.  The only way I am sure it will work on location is by buying great gear and great cases.  I bought cheap stuff when I started out and I regret it; that stuff never lasts that long.  
Title: Re: How much strobe power is 'enough'?
Post by: Ken Bennett on October 31, 2013, 03:28:53 pm

Higher ISO helps, like a clean 800, cuts your need for w/s.


This is true, except when trying to balance flash with daylight. Then you just need a lot of flash power. But indoors, or at dusk, yes -- raising the ISO helps.

I have several different flash systems (not a great idea, but it's what I have.) The Elinchrom Ranger 1100w/s battery system is powerful enough to be the main light in a group shot outdoors, even through a 1-meter octabox. I find that I can use 400 w/s monolights for the fill or the kickers -- I have Dynalite Uni400JR's with the Buff Vagabond Mini batteries. This kit rides in two fairly large rolling cases, and can handle almost anything I need to shoot.

I have several other 400w/s lights, and a 2000w/s Dyna pack, but they don't see as much use.
Title: Re: How much strobe power is 'enough'?
Post by: Doug Peterson on October 31, 2013, 03:37:00 pm

This is true, except when trying to balance flash with daylight. Then you just need a lot of flash power. But indoors, or at dusk, yes -- raising the ISO helps.

I have several different flash systems (not a great idea, but it's what I have.) The Elinchrom Ranger 1100w/s battery system is powerful enough to be the main light in a group shot outdoors, even through a 1-meter octabox. I find that I can use 400 w/s monolights for the fill or the kickers -- I have Dynalite Uni400JR's with the Buff Vagabond Mini batteries. This kit rides in two fairly large rolling cases, and can handle almost anything I need to shoot.

I have several other 400w/s lights, and a 2000w/s Dyna pack, but they don't see as much use.

Or faster native flash sync.

When shooting with the DF+ and an LS lens I can balance daylite with a canon 580EXII at half power. Native ISO of 50 combine with sync at 1/1600th goes a very long way to balancing daylite.
Title: Re: How much strobe power is 'enough'?
Post by: george2787 on October 31, 2013, 03:49:28 pm
I work with 4 500 W/S profoto d1 and a 600 W/S profoto acute B, that covers about 90% of my usual jobs without using any of the units at full power, if I need more power the usual is to rent a 1200W/S profoto battery pack and use the same modifiers to keep it simple and predictable. :)
Title: Re: How much strobe power is 'enough'?
Post by: Ken Bennett on October 31, 2013, 04:25:46 pm
Or faster native flash sync.

When shooting with the DF+ and an LS lens I can balance daylite with a canon 580EXII at half power. Native ISO of 50 combine with sync at 1/1600th goes a very long way to balancing daylite.

Yeah, I could find a lot of use for that :)  Makes me remember why I liked my old MF system so much in the film days.
Title: Re: How much strobe power is 'enough'?
Post by: Joe Towner on November 01, 2013, 01:19:02 pm
Yea, this gives me lots to think about.  Local rental shop has 90% Profoto stuff (and lots of it), and I think it is safe to say that anywhere I go I can find Profoto stuff.  As someone who wants the ISO 50/100 F8/F11 fun, I'm really needing 1k+ strobes.  Thanks for keeping me focused on what I need.
Title: Re: How much strobe power is 'enough'?
Post by: Pics2 on November 02, 2013, 02:56:54 am
Sorry Joe for jumping in your thread with yet another question, but since it's about Profoto lighting and I didn't know where and whom to ask here it goes.
Is the color temperature and quality of light (many say Profoto light has "something") consistent through the entire Profoto line? Can I mix different Profoto products in the same lighting setup without seeing any obvious difference? I have Profoto 7a packs with dedicated heads, but I wanted to add Acute2 with its heads or even compacts to the line? What worries me is that this products are made in different times, with different technologies or whatever. Acute2 are pretty old I think. Thanks!
Title: Re: How much strobe power is 'enough'?
Post by: TMARK on November 02, 2013, 07:29:33 am
Short answer is there is no difference. Long answer is that the color temp may vary slightly, if you measure it. The Pyrex dome is what affects color temp more than anything else. Make sure all the heads have the same dome as profoto made/makes several different domes that were warmer. They usually had holes in them.

I mixed Acute2s Pro6 and Pro7s. No issues with output but recycle times are much different.

Sorry Joe for jumping in your thread with yet another question, but since it's about Profoto lighting and I didn't know where and whom to ask here it goes.
Is the color temperature and quality of light (many say Profoto light has "something") consistent through the entire Profoto line? Can I mix different Profoto products in the same lighting setup without seeing any obvious difference? I have Profoto 7a packs with dedicated heads, but I wanted to add Acute2 with its heads or even compacts to the line? What worries me is that this products are made in different times, with different technologies or whatever. Acute2 are pretty old I think. Thanks!
Title: Re: How much strobe power is 'enough'?
Post by: JoeKitchen on November 02, 2013, 09:20:06 am
Sorry Joe for jumping in your thread with yet another question, but since it's about Profoto lighting and I didn't know where and whom to ask here it goes.
Is the color temperature and quality of light (many say Profoto light has "something") consistent through the entire Profoto line? Can I mix different Profoto products in the same lighting setup without seeing any obvious difference? I have Profoto 7a packs with dedicated heads, but I wanted to add Acute2 with its heads or even compacts to the line? What worries me is that this products are made in different times, with different technologies or whatever. Acute2 are pretty old I think. Thanks!

Plus 1 on this.  There is virtually no different with Profoto; maybe you would be off by 100K but that's it.  The domes are the big concern.  The older domes are not as clean as the updated ones and yellow over time, so you may have to replace them to make it consistent.  Also, Profoto does sell two different kinds of domes; I believe it a 5500K dome and 5700K dome. 
Title: Re: How much strobe power is 'enough'?
Post by: JKevinScott on November 02, 2013, 11:28:15 am
Another thing to consider when you're deciding how much power you need is recycle time.  More powerful packs and monoblocks typically give you better performance.  I frequently use a single-light setup for ISO 50 and f/11 that requires about 450 W/S of output.  Recycle time for that output on my 1200 W/S pack is about 1 second.  Recycle time for the same 450 W/S on a 3200 W/S pack is at least 4x faster on the (granted informal) side by side that I just did.  That can be the difference between capturing the moment versus getting a black frame because your strobe(s) didn't fire. 
Title: Re: How much strobe power is 'enough'?
Post by: Pics2 on November 02, 2013, 12:28:17 pm
Thank you TMARK and JoeKitchen for the valuable info!
Title: Re: How much strobe power is 'enough'?
Post by: TMARK on November 02, 2013, 04:49:32 pm
I have fuzzy memory of a 4800k dome, and one that wasn't UV coated.

One more thing, the D1 Monos don't have a dome, they have a glass disk.  While I like the disk with an umbrella, I prefer the domes for use with any other modifiers or for a bare bulb effect.  They make a dome for the D1 series.   

Plus 1 on this.  There is virtually no different with Profoto; maybe you would be off by 100K but that's it.  The domes are the big concern.  The older domes are not as clean as the updated ones and yellow over time, so you may have to replace them to make it consistent.  Also, Profoto does sell two different kinds of domes; I believe it a 5500K dome and 5700K dome. 
Title: Re: How much strobe power is 'enough'?
Post by: Yanick Dery on November 02, 2013, 08:25:50 pm
I shot with the H4D-50 for the Cirque du Soleil.

I had only 2 power pack Profoto Pro 7A 2400 with 5 heads.

here is what I did. You can see some picture done during the live performance shot with the 5D, compare to the stage performance with no light from the show, only flash, with the H4D.

http://web.yanickdery.com/15584-live-vs-setup

All picture has not been retouched. Only calibrated in Lightroom.


More to read : http://web.yanickdery.com/pages/6667-cirque-du-soleil
Title: Re: How much strobe power is 'enough'?
Post by: Ken R on November 02, 2013, 09:00:31 pm
I used my strobes once for stop motion animation and I did notice some variation between some exposures (in light output not color balance) it was very slight but it was there. I found out that if I wait a lot between shots then the first pop after the wait is a tad more intense. Were are talking a tenth of a stop maybe but it is noticeable. What I do now is that I pop the flash before the shot and then take the shot normally if I had to wait a bit before the shot. Seems to work well.

I have seen color temperature variations between soft boxes and light modifiers. If I know I will be using softboxes in pairs a lot then I buy two at a time. I did that with the strip boxes. I use a pair for product shots and got two identical ones and they work perfectly. Also try to use the same brand of soft box. I use mostly chimera. Store and take care of the well and they should last quite a bit without yellowing or changing color.

I really like the light quality from the profoto frosted domes. You really notice a difference when using bare reflectors.
Title: Re: How much strobe power is 'enough'?
Post by: ErikKaffehr on November 03, 2013, 05:53:21 am
Hi,

Nice work and thanks for telling about it!

Best regards
Erik

I shot with the H4D-50 for the Cirque du Soleil.

I had only 2 power pack Profoto Pro 7A 2400 with 5 heads.

here is what I did. You can see some picture done during the live performance shot with the 5D, compare to the stage performance with no light from the show, only flash, with the H4D.

http://web.yanickdery.com/15584-live-vs-setup

All picture has not been retouched. Only calibrated in Lightroom.


More to read : http://web.yanickdery.com/pages/6667-cirque-du-soleil
Title: Re: How much strobe power is 'enough'?
Post by: Joe Towner on November 04, 2013, 04:17:02 pm
Thank you Yanick, a great write up plus side by sides for staged and live.

-Joe

I shot with the H4D-50 for the Cirque du Soleil.

I had only 2 power pack Profoto Pro 7A 2400 with 5 heads.
Title: Re: How much strobe power is 'enough'?
Post by: JoeKitchen on November 04, 2013, 10:28:14 pm
I have fuzzy memory of a 4800k dome, and one that wasn't UV coated.

One more thing, the D1 Monos don't have a dome, they have a glass disk.  While I like the disk with an umbrella, I prefer the domes for use with any other modifiers or for a bare bulb effect.  They make a dome for the D1 series.   


I could be a little fuzzy on the exact Kelvin Temp on the domes.  I do know that one is UV coated and one is not, which changes the Kelvin temp. 
Title: Re: How much strobe power is 'enough'?
Post by: Pics2 on November 06, 2013, 04:25:13 am
It looks like we still need one of these in studio :)
http://www.ebay.com/itm/GOSSEN-COLOR-MASTER-3F-COLOR-METER-W-CASE-FREE-WW-SHIPP-MINT-/151159281898?pt=US_Light_Meters&hash=item2331cb98ea
Title: Re: How much strobe power is 'enough'?
Post by: synn on November 09, 2013, 09:04:39 am
Hi,

In my experience, strobe photography is never about absolute power, but relative power against whatever your conditions present. As mentioned earlier in the thread, having a higher native sync (And not silly HSS) goes a long way in making small strobes put out big light on location. For example, I have noticed that several people complain on the forums that the Elinchrom Quadras are "Not powerful enough to overpower the sun". In my experience, it really depends on how you use them. With Pocketwizard Plus IIIs and the Nikon D800, I have managed to sync the quadras up to 1/320s, which coupled with an efficient light modifier such as the Maxilite reflector is enough to overpower the sun even here in tropical Singapore.

Here's an example at 1/250s and the maxilite. 1/320s would help cut another third of a stop of ambient.

(http://farm3.staticflickr.com/2873/9276826826_2f950e103e_c.jpg)

Shot at 1PM.

Since you need to shoot 8 people or so, I would recommend the use of a highly efficient modifier such as the Paul C Buff PLMs (You'll need sandbags and strong assistants if you want to use them outdoors, though). The Einsteins and the PLMs should be more than enough for your application, helped very much by the 1/800s sync that you get from the Hasselblad.

I have gone through the modifier acquisition syndrome, but eventually, realized that the Maxilite, the deep octa and the PLM are my go-to mods (Or good old reflective umbrellas if I am working with speedlights and moving fast). I'd recommend the PLM to everyone. It's not an "easy" mod to use as in, you can't just  pop a strobe into it and expect gorgeous light as you would with an octa. You have to understand its character a bit before you "Get" it, but once you do,  every strobe based photographer will benefit from this wonderful mod.