Studio lighting queries

Couple of questions regarding studio lighting:

1a. Are the GN numbers for speedlites a similar yardstick for studio lights? For instance, my 580ex2 has GN58, which is more powerful than a Jinbei DM2-400 flash with GN56?

1b. Assuming full power on my 580ex2 is more than sufficient for indoor studio needs and taking recycle time and modelling light aside, what other advantages do I get from using monolights?

2. For strictly indoor studio environment, shooting portraits with a 100cm Octabox, how many Ws should I aim for? 300Ws sufficient?

3. What are the recommended models that are value-for-money and have consistent shot-to-shot WB? Understand that AlienBees are very popular, but unfortunately they cost a bomb to be shipped to my area. Welcome other suggestions (even OEMs, off-brands) please!

4. Same question as Q3 - recommended model for a huge octabox that is easy to assemble and disassemble? I remember there was 1 model that acts like an umbrella and is easy to store - any downsides to such a mechanism?

Thanks in advance for your help!

the.forumer wrote in post #17299260
what other advantages do I get from using monolights?

Bare bulb of mono light fills a modifer better, they also allow the use of reflectors.

the.forumer wrote in post #17299260
For strictly indoor studio environment, shooting portraits with a 100cm Octabox, how many Ws should I aim for? 300Ws sufficient?

This isn't as much of an issue considering the ISO capabilities of the new cameras. When you start mixing different modifiers in multiple lighting set ups is where you need to think about possibly having lights of different out puts.

What ever you do, don't go cheap. By that I mean for you to purchase descent equipment, not Pro Photo, but along the lines of Einsteins would be a good starting point. I don't shoot with Einsteins.

1) No the guide number is a not sn sccurate method of comparing studio strobes. Guide numbers for speedlites csn be optimized by using focused fresnrl lenses. Stufio stobes are bare bulbs. Generally studio strobes are compared by their watt second rating which equates to how muvh power they put out. Be wary of ads that use wsttd instead of watt seconds as their measurement. Some have tried to measure studio strobes in gn terms but its very imprecise.

2) Your assumption sbout the power of the 580exII is likley wrong (youll want more power). But setting thst aside the biggest drawback of speedlites is the focusef heads. That limits the size of modifier you csn use snd size equals softness. The bare bulb of a single monolight csn fill a 7ft plm or octobox where a speedlite may struggle to fill a 30 inch softbox.

3) Be wary of off brands or internet kits. They seem enticing but oftrn they come with proprietary mojnting systems or flash tubes that can't be replaced easily. Bettrr to buy a single light from a brsnd name maker and build a kit as the budget allows than blow it on crap. I cant make specific recommdations on brands because of not knowing your local availability.

4) consider a plm with a diffusion panel instead of an octobox, but if you want an octo you ought to decide on the specific brand of light before moving o the modifier because of the mount design issues.

The problem with any attempt at comparison of speedlight vs. studio head is that it fails to consider that...

• A speedlight zoom head changes its angle of coverage in order to makes its output SEEM BETTER than it really is! (Didja know that every ETTL flash today is WEAKER in light output than the 30 year old Metz 45CL flash..and the ETTL flash is only 'brighter' at its 105mm setting?!)
  
• Studio heads permit changing the reflector, not only for angle of coverage but also (in the case of some flash heads) the reflectivity of the surface of the reflector, as well as optimizing the head for use in softboxes.
  

1a. Are the GN numbers for speedlites a similar yardstick for studio lights? For instance, my 580ex2 has GN58, which is more powerful than a Jinbei DM2-400 flash with GN56?

As above, your speedlight is being measured at the long end of the zoom, at more normal angles the effective power is likely a quarter of the advertised GN. GN numbers for studio heads are often under reported too, because there's no standard reflector to use as a measure.

1b. Assuming full power on my 580ex2 is more than sufficient for indoor studio needs and taking recycle time and modelling light aside, what other advantages do I get from using monolights?

It's probably not if you're using large modifiers. Don't underestimate recycle times or modelling lights.

2. For strictly indoor studio environment, shooting portraits with a 100cm Octabox, how many Ws should I aim for? 300Ws sufficient?

Depending on your space, and considering that you can raise your ISO, you can get away with 200ws or 300ws for a home studio.

3. What are the recommended models that are value-for-money and have consistent shot-to-shot WB? Understand that AlienBees are very popular, but unfortunately they cost a bomb to be shipped to my area. Welcome other suggestions (even OEMs, off-brands) please!

It'll probably help to know where 'your area' is.

4. Same question as Q3 - recommended model for a huge octabox that is easy to assemble and disassemble? I remember there was 1 model that acts like an umbrella and is easy to store - any downsides to such a mechanism?

For a nome studio, go for any of the easy to assemble units, the old speedring/rod system is too fiddly for occasional use, can't recommend a supplier till we know where you are.