This is a subject that will take some drawings and detailed explanation.

Briefly, the IGBT flashtube control works entirely differently than normal studio lights. I don't have the exact final durations yet, but assume Einstein achieves 1/2000 t.5 at full power. This means that at 1/2000 of a second half the flash has been dissipated (see: viewtopic.php?f=5&t=59 )

At Full power it acts exactly like an AB or WL (or Elinchrom, Profoto, etc) and the t.1 time would be about 1/650 (three times as long).

But at half power, the flashtube is shut off at the half power point (1/2000) and there is no trailing tail. So the t.1 time becomes about 1/2000 at half power - vastly shorter, instead of longer as you would find in a conventional system.

At 1/4 power, the tube would be shut off at somewhere around 1/4000 second and the t.1 time becomes 1/4000 second.

With this type of circuitry (similar to Broncolor Grafit) the t.5 spec is no longer very useful once you reduce power from Full because the tube shuts off sharply instead of trailing off. This results in very short t.1 times (as well as shorter t.5 times) and the three to one relations no longer applies.

For this reason, the display of flash duration on Einstein and Cyber Commander are t.1 times - the more accurate comparison of flash duration to equivalent shutter speeds in cameras used with continuous light.

Bottom line is at any power below Full, Einstein will achieve extremely fast and ghost free action stopping.

any chance a profoto adapter would be made as well? or just making some sort of adjustable beam reflector like profoto has?

Profoto compatibility is not high on the list at this point.

So if logic follows were tentavively looking at a 1/1300 sec t.1 full-power flash duration on the 500ws model?

Sorry to probe so much, but I'm excited about a possible alternative to dropping $$$$ on a ranger. Just doing my research...

Your logic is close. I don't have the exact numbers yet. But remember, if you drop the Einstein flashpower 1/2f to 1f you will see t.1 times more like 1/2000 to 1/3000.

For reference, the Ranger in the attachment 1100WS has a t.5 duration of 1/2300 with one head. This is a t.1 of around 1/750. In the neighborhood of a Zeus 1250 with one head. But neither have IGBT controlled flashes so they will have a trailing fall off and ghosting. Since the variable power is still caused by adjusting voltage, the durations will get longer as you reduce power with the variator. If you use multiple heads, or switch capacitors out to reduce power you will shorten the t.5 times, but still have the trailing fall off and ghosting.

On Einstein (and Grafit) as you reduce power you clip the trail off and achieve much faster t.1 times with no ghosting.

http://www.bhphotovideo.com/c/product/3 ... 0_W_S.html

[quote="Luap"]Your logic is close. I don't have the exact numbers yet. But remember, if you drop the Einstein flashpower 1/2f to 1f you will see t.1 times more like 1/2000 to 1/3000.

For reference, the Ranger in the attachment 1100WS has a t.5 duration of 1/2300 with one head. This is a t.1 of around 1/750. In the neighborhood of a Zeus 1250 with one head. But neither have IGBT controlled flashes so they will have a trailing fall off and ghosting. Since the variable power is still caused by adjusting voltage, the durations will get longer as you reduce power with the variator. If you use multiple heads, or switch capacitors out to reduce power you will shorten the t.5 times, but still have the trailing fall off and ghosting.

On Einstein (and Grafit) as you reduce power you clip the trail off and achieve much faster t.1 times with no ghosting.

http://www.bhphotovideo.com/c/product/3 ... 0_W_S.html[/quote]

Understood on the IGBT control. I'm mainly probing to find out the max power that can be achieved at at-least 1/1500 sec t.1 (which you have answered). Goes back to that whole ski/snowboard photo thing; you need muchos power because you often have to place the strobes far away from the subject so they don't hit them or because you have to cover a large scene, and sometimes overpower extremely bright daylight. You also have to have very fast flash durations for obvious reasons (to much motion blur with my old B800; not enough power with my AB400). Combine that with the fact that they need to run on batteries AND you have to be able to ski/hike in snow with them then you can see why we snowboard/ski photogs need specialized products and the choices are slim (and expensive). Einstein (so far) sounds promising and has more than a few of us anxious to know more. And I do appreciate you sharing information about a yet to be released product.

to second what Ben is talking about we need a lot of power per head with shorter durations than what's out there on the market currently. My heads are typically 50-100 feet away, with the subject being 20-30 feet up in the air as well. weight is a massive issue as well. Is there any chance you'd go to a more powerful head than a 1000ws in the Einstein series? Just wondering for durations sake since powering down to 1/2 seems to have such a huge effect on t.1 durations.

Simply put what ski/snowboard photographers really want does not exist on the market. We want 1200+ws with 1/1000 t.1 durations that get quicker as we power down.....all in something lighter than a 10lb kit. Because of this a lot of guys on the snowboard end have both a Ranger and a 7b kit.

Guys, I'm guessing you'd get significantly more bang per kg/lb compared to a Ranger. Regardless, with the Einsteins you could taylor the weight by having a number of different sized 12v batteries in your trunk. The Ranger only offers one battery size.

The Ranger is advertised as having 2.3 Kg head, + 8Kg generator/battery. This is strangely heavy (IMHO) for a head that is relying on a power pack to do all the work.

If your shooting session wasn't overly long, you could take 2x Einsteins with smallish batteries- meaning not much more weight than 1x Ranger, but 1024 w/s at perhaps 1/2000 T1, by using them both together at half power.

It's sounding like 2x Einsteins will only cost around the same as (or less than) 1x Ranger RX "A" kit anyway.

[quote="Shoebox9"]Guys, I'm guessing you'd get significantly more bang per kg/lb compared to a Ranger. Regardless, with the Einsteins you could taylor the weight by having a number of different sized 12v batteries in your trunk. The Ranger only offers one battery size.

The Ranger is advertised as having 2.3 Kg head, + 8Kg generator/battery. This is strangely heavy (IMHO) for a head that is relying on a power pack to do all the work.

If your shooting session wasn't overly long, you could take 2x Einsteins with smallish batteries- meaning not much more weight than 1x Ranger, but 1024 w/s at perhaps 1/2000 T1, by using them both together at half power.

It's sounding like 2x Einsteins will only cost around the same as (or less than) 1x Ranger RX "A" kit anyway.[/quote]

That's why were probing Paul for info on the Einstein.

The problem is really how much power you put through the capacitors and flashtubes at short durations VS reliability. Zeus and Ranger are pushing the limits in this regard. When you get into IGBTs you would have to start paralleling 20 or 30 IGBTs (they're expensive). We can do shorter durations but it really invites failures and short tube life.

You'll be able to get somewhat faster durations for a given amount of WS from the Einstein 1000 because you are starting with more power.

The starting point should be looking a more focused reflectors to get more of the available power to the distant subject and using more than one light.

But don't forget the IGBT tube shutoff really helps because there is no ghosting. You can simulate this by using a D40 style camera set to 1/2000 second exposure time with a B1600 - see viewtopic.php?f=2&t=6176

I've always wondered if the technology existed to produce a somewhat affordable and compact 1200 WS flash with 1/1000 t.1 flash duration that speeds up as the power is turned down and companies just didn't make them because of what they perceive as a limited market.

Actually, Zeus 1250WS with bi tube head accomplishes 1/1000 second t.1.

The reason studio flash units don't get faster as you reduce power is because the UGBTs needed to accomplish this at high power levels have not been economically feasible until quite recently, and multiple IGBTs are needed in a unit like Einstein. This is why $8000 Grafit Packs were the first to use this technology.

The Chinese Photogenic lights
http://www.bhphotovideo.com/c/product/4 ... x_III.html
do use this sort of technology, but they have a very long initial flash duration (1/125 at 320WS) so there is much less current through the IGBTs - much like the low power speedlights that use this technology.

But then with Zeus you also need to carry a Vagabond or be near AC. That goes back to using more lights with more focused reflectors: more stuff and weight. Not impossible, but you can only carry so much gear. It probably looks absurd to a studio or football photographer to watch one of us haul snowboard gear, a full DSLR rig, lightstands, and a Ranger through two feet of snow for a quarter mile uphill at 10,000 feet in elevation.

Like Seowitz said, what we want doesn't exist so we make due with what's available. Of course, what would be ideal is shoe-mount sized speedlight with a GN of 1000 and a max flash duation of 1/1500 sec t.1 for like $100 or something. And magical unicorns to fly us up the mountain, too.

I feel for you snowboard guys.

A major problem you may always face is that the vast majority of the strobe market would be very happy to add some extra weight (ie heatsinks etc) if this translates into faster recycle times. I gather you don't care about recycle times (ie only one shot per jump anyway) but don't want to hire motorised transport for every shoot.

Or am I wrong- do you want fast recycles as well?

It's not about extra weight and heat sinks and such. There are limitations to how fast you can charge x amount of capacitors without blowing fuses or demanding more than a battery can deliver. There are also limitations to how fast you can dump the capacitor charge into the flashtube without damaging the capacitors, tubes and circuitry.

Einstein delivers the minimum practical recycle times and the minimum practical flash durations consistent with reliable and durable performance, in the smallest and lightest possible package and the highest possible degree of accuracy, control and display. It's not about money or weight - its physics and intelligent design and engineering.