Quenchtime database

[tim10243]

Hi,
when I take a look at Tills software architecture
http://code.google.com/p/strobist-project-opensource-trigger/wiki/SoftwareArchitecture
i see the point "Devices" when the Spot is set on "Receiver". So you
can preset the quenchtimes for more than one flash, I guess. Now befor
everyone is trying to find out the quenchtimes for everey flash he
might use by try and error, wouldn´t it make sense to create a little
database with quenchtimes? it looks like the quenchtimes which are
given by the manufaktures are not the ones we need here for the spot.
if you compare Tills quenchtimes for the SB-24 with the times from the
nikon manual, you´ll see the difference:

Tills times:
150 µ sec @ 1/1 (full) output
64 µ sec @ 1/2 output
32 µ sec @ 1/4 output
19 µ sec @ 1/8 output
13 µ sec @ 1/16 output
9 µ sec @ 1/32 output
7 µ sec @ 1/64 output

Nikon manual times:
100 µ sec @ 1/1 (full) output
91 µ sec @ 1/2 output
37 µ sec @ 1/4 output
18 µ sec @ 1/8 output
9 µ sec @ 1/16 output

tim

[Till Seyfarth]

Good call! I'll set up a table in the software chapter of the wiki.

[Till Seyfarth]

Ok, done. Your input please!

 

Note: The timings in rfm12.c do not represent microseconds but 1/100.000 seconds. This means that e.g. my measurement for 1/16th output power is 130 µs and not 13 µs. No idea how this corresponds to Tim's numbers from the Nikon manual. Seems it doesn't.

[tim10243]

just to see if a made a mistake :

what I got from the manual:
1/1000 sec. @ 1/1 (full) output
1/1100 sec. @ 1/2 output
1/2700 sec. @ 1/4 output
1/5500 sec. @ 1/8 output
1/11000 sec. @ 1/16 output

that would be:
0,001 sec @ 1/1 (full) output
0,00091 sec @ 1/2 output
0,00037 sec @ 1/4 output
0,00018 sec @ 1/8 output
0,00009 sec @ 1/16 output

or:

> On Thu, Sep 10, 2009 at 1:10 PM, Till Seyfarth <tillseyfa...@gmail.com>wrote:
>
> > Good call! I'll set up a table in the software chapter of the wiki.
>
> > On Thu, Sep 10, 2009 at 12:11 PM, tim10243 <t...@brakemeier.info> wrote:
>
> >> Hi,
> >> when I take a look at Tills software architecture
>

> >>http://code.google.com/p/strobist-project-opensource-trigger/wiki/Sof...

[Till Seyfarth]

Yes there's a mistake in the last step: 1 micro second is one millionth second or 10^(-6)s.

 

For example: 1/1000s = 1x10^(-3) = 1000x10^(-6) = 1000µs.

[tim10243]

thanks - i´ll correct that
quenchtimes for the SB-80DX and the DSB-800 measured by "fotoopa" can
be found here:
http://www.flickr.com/photos/fotoopa_hs/3709381751/in/set-72157611107153997/

[Mathe]

I don't want to spoil this thread, but the timings mentioned in
several Nikon Speedlight manuals are not quench time values but flash
duration values.
And yes, these timings are different. From the measurements I did I
came to quench values being sometimes half the flash duration time.

btw, I stepped away from the multi flash type concept two months ago.
After all, it doesn't really matter if you are right on the timing or
maybe 1/4 or 1/2 stop too high or too low.
I mean, the value's aren't absolute. Move one flash for 50cm and your
lightning scheme can become quite different.
So I've ended up with one generic timetable for all the Nikon
Speedlight flashes that I have (5 different types). It will need a
little fine tuning for the 1/64, 1/96 and 1/128 values but for now
it's working to my satisfaction. I did however add 1/2 steps to the
software which is really helpfull.

Marc

On 10 sep, 15:31, tim10243 <t...@brakemeier.info> wrote:
> thanks - i´ll correct that
> quenchtimes for the SB-80DX and the DSB-800 measured by "fotoopa" can

> be found here:http://www.flickr.com/photos/fotoopa_hs/3709381751/in/set-72157611107...

> > > > >> tim- Tekst uit oorspronkelijk bericht niet weergeven -
>
> - Tekst uit oorspronkelijk bericht weergeven -

[tim10243]

hi marc,
could you publish that part of the software which contains the half
stop steps?
you are right - all the nikon flashes sems to be very close to each
other. but my good old metz 60ct-1 for example has total differnet
times.
thanks
tim

[Till Seyfarth]

Hi Marc,

 

you're right: the timings in the manuals are not the timings we need for the SPOT. But the hope is that they can serve as starting points or hints for getting the numbers right. Within one brand they seem fairly similar but when I look at the Metz model it looks quite a bit different. I'll clarify the distinction between burn times and SPOT quench times in the documentation.

 

The power values are not absolutes - full power of one type is different from full power of another. But for me it seems important to be able to stop down a flash more or less precisely one or 1/2 stop (half stops are still on my to-do list) because it corresponds to the way we control our cameras: More depth of field needed, exposure ok? Simply stop down the lens and stop up the flash by the same amount. So I'll stick to the exact route for the time being. I'm just hoping that there's not too much variance between units of one type. 

 

Cheers

Till

[Mathe]

Hi Tim,

I have my current project files at: www.vaenw.nl/temp/Spot107.rar
Please make it usefull :)

@ Till, you're right if you want to use it that way.
I probably work somewhat different. For me it doesn't matter if I'm
shooting 1/4 or a 1/2 stop underexposed.

Marc

> > > - Tekst uit oorspronkelijk bericht weergeven -- Tekst uit oorspronkelijk bericht niet weergeven -

[Stephen Eaton]

Hi Guys,

 

It might be worth looking at the type of timing data captured by Frans and his work on his project for capturing insects in flight.

 

This type of information I feel is what we require in the database.  His setup is fairly simple for collecting the timing data of the different types of strobes.   I've been in correspondence with Frans and he pretty well has a working prototype for his high speed wireless unit based on the RFM12B (Frans may be lurking on the list so please feel free to give us an update :) )  I also love the simplicity of his firmware for high speed sync by using a sequencer to independanty control the timing of up to 4 strobes per slave (see the diagrams below)

 

http://www.flickr.com/photos/fotoopa_hs/3709381751/in/set-72157611107153997/

http://www.flickr.com/photos/fotoopa_hs/3709619306/in/set-72157611107153997/

http://www.flickr.com/photos/fotoopa_hs/3798474398/in/set-72157611107153997/

http://www.flickr.com/photos/fotoopa_hs/3778250766/in/set-72157611107153997/

 

Regards,

 

Stephen...

---

From: spot-dev...@googlegroups.com [mailto:spot-dev...@googlegroups.com] On Behalf Of Till Seyfarth
Sent: Friday, 11 September 2009 2:58 AM
To: spot-dev...@googlegroups.com
Subject: Re: Quenchtime database

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[Till Seyfarth]

Hi Stephen,

 

the data for SB-80-DX and SB800 (here: http://code.google.com/p/strobist-project-opensource-trigger/wiki/SoftwareArchitecture) are from Frans. I've noted under the table that he uses a different hardware. This has probably less of an effect on timing than using burn times but an adaptation may still be required.

 

Cheers

Till

[gandalf el gris]

Hi mates

Any body knows the Quenchtime for Canon Flashes... Cause many off us we use canon. Or anybody knows how to built it from scratch?

Thanks.

2009/9/11 Till Seyfarth <tillse...@gmail.com>

--
“Dios no juega a los dados”. Albert Einstein. “¡Einstein, deja de decirle a Dios lo que debe hacer!”. Niels Bohr

[tim10243]

the new radiopopper JrX - which is abel to make a manual power control
of speedlights as well - has just one quenchtime; its the one for the
nikon sb-800. i don´t think that they would use a quenchtime which is
absolute out of use for canon photographers. so the canon flash
quenchtimes must be in the same area as the nikon flashes.

On 11 Sep., 10:42, gandalf el gris <gandalf.el.g...@gmail.com> wrote:
> Hi mates
>
> Any body knows the Quenchtime for Canon Flashes... Cause many off us we use
> canon. Or anybody knows how to built it from scratch?
>
> Thanks.
>

> 2009/9/11 Till Seyfarth <tillseyfa...@gmail.com>

>
>
>
> > Hi Stephen,
>
> > the data for SB-80-DX and SB800 (here:

> >http://code.google.com/p/strobist-project-opensource-trigger/wiki/Sof...) are

> > from Frans. I've noted under the table that he uses a different hardware.
> > This has probably less of an effect on timing than using burn times but an
> > adaptation may still be required.
>
> > Cheers
> > Till
>

> > On Fri, Sep 11, 2009 at 5:15 AM, Stephen Eaton <madeino...@gmail.com>wrote:
>
> >>  Hi Guys,
>
> >> It might be worth looking at the type of timing data captured by Frans and
> >> his work on his project for capturing insects in flight.
>
> >> This type of information I feel is what we require in the database.  His
> >> setup is fairly simple for collecting the timing data of the different types
> >> of strobes.   I've been in correspondence with Frans and he pretty well has
> >> a working prototype for his high speed wireless unit based on the RFM12B
> >> (Frans may be lurking on the list so please feel free to give us an update
> >> :) )  I also love the simplicity of his firmware for high speed sync by
> >> using a sequencer to independanty control the timing of up to 4 strobes per
> >> slave (see the diagrams below)
>

> >>http://www.flickr.com/photos/fotoopa_hs/3709381751/in/set-72157611107...
>
> >>http://www.flickr.com/photos/fotoopa_hs/3709619306/in/set-72157611107...
>
> >>http://www.flickr.com/photos/fotoopa_hs/3798474398/in/set-72157611107...
>
> >>http://www.flickr.com/photos/fotoopa_hs/3778250766/in/set-72157611107...

[Konstantin]

On Fri, Sep 11, 2009 at 11:42 AM, gandalf el gris
<gandalf...@gmail.com> wrote:
> Any body knows the Quenchtime for Canon Flashes... Cause many off us we use
> canon. Or anybody knows how to built it from scratch?

I'ts got to be some pretty old Canon. AFAIK none of the newer
EX-series flashes have a quench pin.

[Mathe]

> I'ts got to be some pretty old Canon. AFAIK none of the newer
> EX-series flashes have a quench pin.

And neither does Nikon's SB-900.

Marc

On 11 sep, 11:43, Konstantin <beowulfena...@gmail.com> wrote:
> On Fri, Sep 11, 2009 at 11:42 AM, gandalf el gris
>

[fotoopa]

I've updated the timings and added also the ringflash SB-29-S.
See: http://www.flickr.com/photos/fotoopa_hs/3940946688/
To have full advantage of the lower powerrange you need more precise
timings. The ringflash SB-29-S can even go to 1/512 power in 1/3 EV
steps. But you need timingsteps of max 1 us. Now on my testunit (see
picture on Flickr) I have 2 usec resolution. In a little while this
will be changed to 1 usec with the use of the Atmega328p ( more SRAM
into the controller). As you can read on my Flickr web, I used a more
precise methode to define the timings. Now there are very accurate and
reliable.

As highspeed user i need for shure the more lower power side of the
flashes to freeze better the action without blur. If you can only go
to 1/64 power this is certainly to little in range. I recommend to
expand your powerrange table.