Very good explanation from Mark Wallace the OG Adorama TV host!

Great videos survive decades. Thank you!

This is by far one of the most informative and accurate video tutorials I've ever watched... Looking forward to watching more!

Excellent video. You've answered so many questions I couldn't answer on my own since I don't have access to so many strobes to experiment with. One of the best informational videos available IMHO.

Mark Wallace, you pass the information very easily. Soon there'll be attending his workshops. Thank you!

Whenever I need an answer, I always find it in your videos & more. Thanks Mark!

I love Mark Wallace he is my number one on KZfaq

Great Video. Just as a note. It seems that the initial test distance is 15' and that all flashes are using the umbrella type reflectors. Different manufacturers like Profoto have these and they can increase output 2-3 times. When using umbrellas and other light modifiers the F-Stops are reduced. In the first case I had a similar situation and resorted to turning the whole umbrella towards the wall and use the white wall as the reflector. You can also use a transparent umbrella and reverse it so it faces the wall and have beautiful soft light on model with softening of the room. Gabriel Hernandez Photography

As a longtime Norman user, on my big pack/2000ws, the smallest setting is 200w. So if I need even less power, I just use a 10" ND gel filter on the flash tube, reducing it by one stop. But Mark is right....choosing the right power for the "right room".

Assuming a 10 ft (3 meter) distance between flash and meter, at 100 ISO, these are the guide numbers (GN). The unit depends on the distance unit (meters or feet). It also varies per ISO. Here the meter was at ISO 100. Brand Model GnM GnFt Note Profoto D1 1000 77 253 Flashpoint 2420 77 251 Flashpoint 1220M 61 201 Profoto D1 500 56 182 Einstein E640 55 181 Profoto Acute2 1200 49 162 (1) AlienBee B800 40 131 (2) (1) this Profoto equaled the D1 1000 with a newer reflector that was zoomed in (narrower beam). (2) here we arrive in the on-camera flash (speedlight) power range. Mark shows it is potentially more important how low you can go with Ws. And this brings you in the speedlight territory. I would add that more important are consistency of color temperature over the power range, duration (shortness) of the flash as ability to freeze motion and consistency between repeated flashes. And of course recycle time between flashes. Cheaper generally does worse in the consistency areas as well as recycle times. Some strobes require you to "dump" when you adjust Ws down - a a give-away of old (now cheap) technology.

I don't know what to say how perfect and useful it was, Thank you

Adorama does it again, explain a complex theory in the way I understand. Thank you.

Mark, your videos are outstanding, and always immensely helpful. Your enthusiasm helps a lot, too. I just wanted to say thank you very much for these videos. I feel like I've learned the equivalent of many classes worth of stuff watching your videos.

Cool vid Mark! Love the real world examples. All things being equal (same flash brand and modifiers), like Profoto D1 500 vs. 1000, the extra energy translated directly into light: you doubled the Ws, you got exactly one stop more light (f/18 to f/25 is exactly one stop).

Rewatch the video from :37- 1:27 or so. Although he doesn't get into the science behind Watt-seconds, he does explain how they work in layman's terms.

everybody is talking about the episode and how great it is but I'll say that this is my favorite model ever !!! shes so beautiful :) very educative episode too.. well done !!

Great video again Mark. However, I wished that you had included the Einstein in all the tests. They are cost effective, digital and may even compete with some of the more expensive flash units.

Good video, I wish you would have talked about how watt-seconds impacts flash duration - i.e. freezing motion without increasing shutter speed.

Excellent video!

This episode = gold. Thanks mark!

Wonderful video , I am learning so much by watching your videos.....Great job !!!

this explained so much. Thanks Mark and Adorama

Excellent Mark! Cleared a lot of doubts I had. Keep up the good work.

"If I shoot behind the umbrella...well, I have issues." LOL :) Mark, I learned more in this video than in my months of research/Internet plodding. Thank you!

Great video! Thoroughly explained. Thanks very much....

Guide number = f/stop x distance. Your GN of 58 is in meters (the higher number 191 is in feet). That means that at full power and bare you can get f/22 at 2.6m from your subject... or f/19 at 10ft from your subject. But add a diffuser to soften the hard light of that little light source and you'lll lose 2 stops (f/11 at 2.6m or f/9 at 10ft). And that's at full power meaning slow recycle times.... to speed up the recycle bump the power down to 1/2 or 1/4 and you lose another stop or two.

Excellent video. Definitely the best i have seen on this topic. I am looking for some basic light set ups with say 2 or 3 lamps. If anyone knows of one please leave me a reply. Thanks!

One of your best, Mark. Well done and very informative. And I love your dog. Mine does the same when I trying out stuff in the garage. cheers!

Thanks for the info. This video cleared up a lot of confusion. I can't wait to get a d1 kit.

Fantastic, relevant and timely info for me! Thank you!

A friend of mine does wet-plate collodion which is about ISO 1 (yes, one). I come from a technical background so watt-seconds and energy and power are pretty straightfoward. Right now, she shoots with 240 watts (electricity) of fluorescent lights for 20 seconds, so the total is 4,800 watt-seconds. Since 20 seconds is well into the reciprocity failure range, I would be willing to bet that 2,000 watt-seconds is a ball-park for enough light. So that got me to thinking that your analogy should be light bulbs. If you buy a 20 watt incandescent bulb and a 20 watt compact fluorescent bulb, the CFL is much brighter. Likewise, with technology changes, the same amount of electrical energy (watt-seconds) can result in different illumination. So watt-seconds is sort-of comparable for the same "generation" of equipment (e.g. same price range and within 2 years age difference) but much less comparable for different generations (e.g. 1/4 the price or 10 years older). Also, is there some kind of standard for total light energy output of a strobe? I've seen "guide numbers" but I wasn't clear if those numbers were comparable between manufacturers. It seemed to be the number of feet at ISO 100, but it doesn't include the aperture so it's kind of meaningless ...

I avoid shooting at f/22 due to loss of slight image focus due to defractions caused by very small apertures for studio shots. F/8 is generally preferred, even an f/4 for a shallow depth of field when needed. A sheet diffuser may be required to soften the flash even more for strobes up close at their lower settings. Now the higher watt/sec is great to overpower outdoor sun, but this is much more effective for hi-sync with shutter speeds 1/2000 to 1/8000 sec to lower the ambient sunlight with larger aperture settings to capture bokeh. This, of course, requires a strobe capable of hi-sync.

. This is very helpful Thanks Mark and Adorama

great shows..........

amazing as always! Thank you for this well-backed tutorial! :D

Thank you sooo much Mark!

Moving the light changes the size of the light source and the wrap of the light. Use ND filters either on camera or on the strobe to maintain the correct strobe distance.

Mark you are my hero :)

WOW Mark great lesson

Mark, your dog is awesome :) So was the video Thanks!!!

For optimal conditions. In photo class I calculated my 430EXII had a proper exposure of f/11 at 10ft giving it a GN of 110. Canon rates it at 141. Could I tell whether f/11 or f/14 was the proper exposure without a light meter? Nope.

Awesome tutorial!!!

THANKS

This was great! Thank you!!!!

Thank you!

Very excellent video

wow what a great video!

Awesome tutorial

very very helpful, always makes me wanna come back :)

Hi Mark, can you make a tutorial on Profoto battery packs? They had a tutorial blog but I think it's no longer available. It would be wonderful if you could do a demonstration! Thank you for the videos!

Love ur work

Thanks Mark

Thanks. Guess I work with continuous light too much. Forgot the basics. Nope, dont want to shoot higher than ISO400. But that would give me a couple of stops to play with. Guess it will be a while before I get a tricked out studio. Cant afford that many lights! But thanks again for the correction. Hope you are having a great day!

this is really informative, cheers.

Great info by the way. thanks

Thanks, very informative!

Once more a amazing episode many thanks for explanations. Other question would be how to compare power of studio heads (Ws) to a system flash "Guide No." e.g. Speedlite 580EX II => 58? Br, Artur

There seems to be too much variants in this test as most of them are attached to different modifiers. The profoto D1 obviously had the Zoom reflector pushed all the way to the max hence giving the strongest output. So it seems the result has a lot to do with the light modifiers. I am still contemplating whether I should invest in a D1 kit. The brocolor silos seems to be a better choice but hack I alright bought some profoto stuff.

How would you set your shutter speed? Are you shooting "aperture priority" and setting matching your aperture with the light meter f-number?

A question about the F2.8 test. You say the only option you have is to move the flash back. What about a ND (Neutral density) filter on the lens? I find more power to be more versitile option

I will honestly go with impact brand heads.. and buy them in a kit.. 2 400w/s Impact Astral Extreme's in a kit.. would do me just fine

love that dog....

nice analogy

Very helpfull. Do you know why so few of these have high speed sync?

This is very helpful. Right now I'm using Profoto D1 1000 and I want to use it outdoors. Any recommendation to what power pack should I buy?

I need this information but i need it on the Elinchrom brx 500. Can you post a review on this light. I also need a review on the Impact VC 500WL not sure if you can do one on this one. If you can that would be great! Thank you

Hello Mark, I'd like all of your old lighting equipment for ... FREE! I really enjoy your video broadcast, please keep up the good work. Peace...

And, can't you use Shutter speed to get the f22 for the group photo? As it is a controlled environment you don't need too much speed to get the picture sharp.

Hi Mark, this is a great comparative video. Thanks a lot. I just want to ask you if you were able to triger D1 1000 with the Sekonic light meter. I have both but can not do that. or did you use the pocket wizard?

Thanks a lot....

Who lies more, Mark, or the Dog?

The only thing I got from this is that I need to spend more. I still have no idea what Ws are. Appreciate the effort but I'm still dumb when it comes to watt seconds :/

do they give accurate Guide Numbers on this products? Thanks.

why not meter it without any light modifier (bare bulb) to eliminate one unnecessary variable?

I have missed an important part of this presentation: How are you triggering all those different flash units with a light meter? AFAIK, only Pocket-Wizard-equipped units can be triggered with Sekonic light meters. Can you please share how you are doing this? I will be upgrading my monolights to Profoto D1's, but now I am concerned that my L-608 meter will not trigger them. Please assist.

Did this turn into a review?

Watt/secs do not equal light output. Got it. But: For those of us not wanting to throw a bunch of money at multiple strobes... Cant we just adjust our ISO and/or shutter speed to get the same effects you got by changing out different strobes?

Hi Mark, can you put a new Profoto B1 on the same test?? Thank you!

Been looking at the Profit B-1 500 w/s battery powered strobe and the Broncolor Sirus L-600 w/s for use in outdoor portraits and fashions stuff. Would these Two high end strobes put out high quality light?

what size parabolic umbrella is that?

I have an odd question if you are still monitoring this channel... I went to the camera store today and the rep stated that the Profoto B1 would not put out enough light to fill a 4'x6' profoto softbox... Is that true or where do I go to see the largest softbox that a monolight should have? Thanks in advance...

what most tool can use for every thing ?

Could be one of your best ;-)

Define digital light v analogue light

What about Versa light 360?

Actually moving the light out of the subject is not the best solution to lower the f stops because it changes the quality of the light reaching the subject. I'd use a good quality ND filter and just o simply use a speedlight (since the distance is too short)

This can save you a LOT of money.... Take the iso of you camera off 100 and take it to 800! 🙈 That will turn your f13 into f22 with the flick of a button 🙉 A good modern digital cam will really have no issues with that at all. My Elinchromes style RX 300 are really all I need even for that one time that I have a bigger location.

F22 for a group shot is outa d park. I shoot groups all the time and f8 is fine. Minimum 35mm. I would be laughed at bringing out that freekin massive brolly.

Exactly my point! :D

I really wish that a speedlight had been in this test as well

so for portrait shots a 200 watts like a godox ad200, could be enough?

Great review Mark! What ISO were you using?

Do you need a pocket wizard for a monolight. (Bowens monolight)

May i know how many watts does a SB-900 gives? thanks

@la041787 Strobes and speedlights are so different in power trying to compare them is not terribly useful. Even under ideal circumstances the most power you can usually expect to get from a speedlight/modifier setup is around f/11. And that is with the flash very close to your subject. However, speedlights gives you less weight, more flexibility, and 'near' strobe performance in a lot of scenarios. But in terms of sheer power, it's not close.

what was the power setting for the flashpoint mono light when shooting at 2.8?

Mark, science DOES matter!

distance?

Why not use a shorter shutter time if the light is too bright? Or heck, even an ND-filter would do, wouldn't it?

Haha, just after last episode i tought that i would want to know about watt-seconds