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Dang, that's very cool.View media item 12641 minimum power i.e. 1/256 power from the AD360 View media item 12640 full power from the AD360, timing of t0.1
Dang, that's very cool.
Me too... I'm half tempted to get one just because.I admit to being a gadget freak
Me too... I'm half tempted to get one just because.
I'll be ignoring this thread now.
I don't want to invade your thread Mike but in case your interested here are some times from my strobes:-
Elinchrom ELB 400 Full power.
HS head advertised v recorded.
t0.5
1/550 1/549 port A (100%)
1/1100 1/1100! port B (33%)
t0.1
1/177 port A
1/411 port B
A head advertised v recorded.
t0.5
1/2800 1/2550 1st pop 1/2710 2nd pop 1/2630 3rd pop, not so consistant as HS head! port A (100%)
1/5700 1/5630 port B (33%)
t0.1 average 1/1050 port A
1/1880 - 1/1910 port B
Canon speedlight 600-exrt mk1
Full power.
t0.5 1/1110
t0.1 1/419
Min power.
t0.5 1/40400
t0.1 1/15900
It seems the readings vary depending on recharge time, maybe tube temp, distance and other factors in my hand held room lit test but it gives an idea, the ELB numbers are close and sometimes spot on but I found head to head pop to pop that some variation was seen, I fired the ELBs perhaps 20 times and recorded the closest to quoted numbers from Elinchrom. I think this meter will reveal some interesting facts about flash durations.
I've always found Elinchrom's claimed flash durations to be very accurate, measured on an oscilloscope, but they do vary slightly - in line with slight fluctuations in brightness. Those changes though are miniscule in practise. The biggest shifts are usually at minimum power.
Canon publishes t.5 flash durations for the 600EX-RT Mk2 which identical to the Mk1 in that respect - page 133 of the handbook http://gdlp01.c-wss.com/gds/6/0300024046/01/600exiirt-im-en.pdf And they are notably different to your figures, if not massively out, ie full power 1/890sec, min power 1/34000sec. My own figures for the 600EX-RT are pretty much the same as Canon's.
Recharge times are critical and figures will be all over the place unless the flash is 100% charged. The flash ready light is an unreliable guide, as are claimed recharge times. It is common for the ready light or beeper to come on at only 60-70% of full charge.
Happy with my 308S.... mainly outdoor with 35mm film though....Anybody want a well trained 458 ?
Mike
Mike, I've just noticed something in the Godox AD200 user handbook re flash durations. Page 14 here http://www.yangwuonline.com/Website PDF/A-030501-PIKA200/PIKA200-MANUAL-WEB.pdf Be interesting to see what you get there.
It says times are measured from the moment of triggering, not from the moment brightness reaches 50% or 10% of peak. Re our previous debate, I think this is wrong and the latter is the accepted standard, used by most other major manufacturers, including Sekonic I think. It's also possible that it's just a mistake in the handbook. It wouldn't be the first time and I've also spotted other obvious errors in there.
The diagram looks correct, so probably just a chinglish error but have been busy photographing, hope to test later today
What is wrong?
Mike
OK this is Sekonic's definition page 101 for those not following http://m.sekonic.com/portals/0/documentation/l-858d_operating_manual_eng.pdf
I find it kind of funny that none of this is about HSS given the title of the post.
Because I was *bored, I put together some drawings to help explain everything.
View attachment 97166
#1 shows the amount of light above 10% output, the duration (T0.1) is the width of the base of that area
#2 shows the same for output above 50% (T0.5)
#3 shows how an IGBT flash reduces output by cutting off the tail, which causes T0.1 and T0.5 times to become more similar
#4 shows their importance relative to the amount of ambient collected. It shows a relatively low intensity of light (height) with a short timeframe (SS). In this scenario the flash peak is significantly overpowering the ambient. And the portion of light below 50% and above 10% is a significant amount of the total of all 3, which means it will contribute significantly to the final image. The result would be a very "flash looking" image.
(below 10% is never considered "significant." I doubt that's actually/entirely true, but maybe only in very specialized applications)
One thing I don't quite understand is the reason for the difference in the left edge of the curves shown in post 5. That should be dictated by capacitor discharge rate and bulb heat up characteristics... I would think it would remain pretty consistent unless there is a change due to residual heat buildup in the bulb or circuitry. Either way, I doubt it's of any real significance for any typical flash application.
*I wasn't bored enough to spend the time on making everything to scale
I suspected that, but somehow I missed the unit change from millisecond to microsecond.You're right, that's just the scaling, which Sekonic has changed on both axes so that the signal fills a good area of the graph and you can see what's what.
That doesn't actually explain it in words, but if you look at the little arrows on the graphic, it clearly shows they are using the correct method (visible on the meter's screen, too). And equally, the Godox graphic clearly shows that, in the handbook at least, they are not
Edit: see my edit on post #20 above, with crossed posts I think you might have missed it.
I have been in touch with them, they agree it is a mistake and it will be amended.
Mike
Not got that far in my testing, what are you seeing there?
Is it the do not exceed 100 and then quoting protection cuts in at 40 & 60?
Yes, that's it.
And though it's not mentioned, I suspect that if you keep going after hitting the over-heat slowdown, shortly after it will shut down completely for 15 mins or so. In other words, it'll never get to 100. Want to test that?!