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Author Topic: Help with flashbulbs!  (Read 12773 times)

Some Guy

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Help with flashbulbs!
« on: August 16, 2014, 11:08:49 am »

I acquired a lot of Press 40 clear flashbulbs so I decided to use them with a Nikon D800.

I'm bouncing them into a large umbrella through a blue filter, similar to a Kodak 80C to Daylight balance them as they are clear bulbs (It's a Lee #202 in an embroidery hoop ahead of the bulb in a 5" diameter clamp-on hardware store reflector).

My Minolta Flash-meter IV says f/5.6 at 10 feet at 1/8 second, which amounts to a GN 56.

My own attempt shows best exposure at f/1.4 at 7 feet against the above which is underexposing, or a GN 10.  Flash-meter sitting there says f/5.6 again and differing by 3 stops.

Question is: "If the Minolta meter is right for f/5.6, yet I am underexposing by maybe 3 stops or f/1.4, can it be the Nikon shutter is maybe firing at some point on the bulb's curve, partially?  If the shutter leads, or maybe closes ahead of the bulb?"

I got this graphic of the bulb's curve:




and was wondering about the 42ms shutter lag time of the Nikon and if that is playing into the curve someplace.  If so how do I correct it?  I guess I could set the shutter for maybe 2 seconds at night and see if the lag is due to it closing too soon, but don't know if it is opening ahead of the bulb.

I am assuming the Nikon's contacts close when the shutter is fully open and not some time delay so the bulb should fire later than the shutter in all cases, but don't know since Nikon does that i-TTL and pre-flash stuff.  I don't know how the contacts timing operate.  I am wired via the remote sync and cord for the flashbulb.

Thanks for any help.

SG
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #1 on: August 20, 2014, 10:39:57 am »

I acquired a lot of Press 40 clear flashbulbs so I decided to use them with a Nikon D800.

I'm bouncing them into a large umbrella through a blue filter, similar to a Kodak 80C to Daylight balance them as they are clear bulbs (It's a Lee #202 in an embroidery hoop ahead of the bulb in a 5" diameter clamp-on hardware store reflector).

My Minolta Flash-meter IV says f/5.6 at 10 feet at 1/8 second, which amounts to a GN 56.

My own attempt shows best exposure at f/1.4 at 7 feet against the above which is underexposing, or a GN 10.  Flash-meter sitting there says f/5.6 again and differing by 3 stops.

Question is: "If the Minolta meter is right for f/5.6, yet I am underexposing by maybe 3 stops or f/1.4, can it be the Nikon shutter is maybe firing at some point on the bulb's curve, partially?  If the shutter leads, or maybe closes ahead of the bulb?"

I got this graphic of the bulb's curve:



and was wondering about the 42ms shutter lag time of the Nikon and if that is playing into the curve someplace.  If so how do I correct it?  I guess I could set the shutter for maybe 2 seconds at night and see if the lag is due to it closing too soon, but don't know if it is opening ahead of the bulb.

I am assuming the Nikon's contacts close when the shutter is fully open and not some time delay so the bulb should fire later than the shutter in all cases, but don't know since Nikon does that i-TTL and pre-flash stuff.  I don't know how the contacts timing operate.  I am wired via the remote sync and cord for the flashbulb.

Thanks for any help.

SG


Why are you doing this? It's a waste of time. No, you cannot correct this! Modern camera equipment is set up to synchronize with electronic flash only!

Flashbulbs were made in two basic types, "focal plane" ("FP") and "regular" ("M").

http://www.bonanza.com/items/like/94489165/Flashbulbs-Sylvania-Focal-Plane-26B-Blue-Dot-Flashbulbs-12-Pack

The difference is how long the flashbulb burned ("FP" flashbulbs had a longer "burn" time, probably achieved by varying the length, alloy, or thickness of the filaments). Shutters had a delay built-in for use with flashbulbs, whereas electronic flash had virtually no delay. Look at an old camera and see there are two flash synch outlets, usually "X" and "M" or "FP".

Here is an old Pentax, with two flash outlets, one for FP flashbulbs and one for electronic flash ("X"):
http://chemicalcameras.files.wordpress.com/2010/11/dsc028511.jpg

Here is a later Pentax, with only one flash terminal, "X":
http://www.adorama.com/alc/files/c4091f493fdebe98ef095a5209949342.jpg

Such a camera cannot synch with flashbulbs of any kind!

In your case, the Nikon shutter is opening and closing before the flashbulb is burning much at all!

Leaf shutters used "M" for flashbulbs and used "regular" flashbulbs. Since the entire area of the image is exposed at once with a leaf shutter, "regular" flashbulbs were fine. Focal-plane shutters do not expose the entire film plane at once, but "wipe" across it in about 1/60 to 1/100 second. This is why the top synch speed for electronic flash is so low with focal-plane shutters.

http://drjlists.home.comcast.net/~drjlists/Flash_Bulbs.htm

http://en.wikipedia.org/wiki/Flash_synchronization

http://en.wikipedia.org/wiki/Flash_(photography)

Focal-plane shutters never could synch with M-class flashbulbs, and modern cameras cannot synch with flashbulbs of any kind!

The only way to use these flashbulbs is in a time-exposure situation. Synchronized flash with them is impossible for the reasons given above. So, throw them away.

http://www.flashbulbs.com/flash_info.htm
« Last Edit: August 20, 2014, 11:26:20 am by melchiorpavone »
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Alto

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Re: Help with flashbulbs!
« Reply #2 on: August 20, 2014, 12:15:11 pm »

Hi


If you do set them off make sure you check the pink/blue spot the blue dot will go pink if there is a fault in the envelope if its pink be prepared for a bang .
Oh and use a glove inc ase of a short.
Use them on B to light large interiors .

Jon
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John Nollendorfs

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Re: Help with flashbulbs!
« Reply #3 on: August 20, 2014, 12:15:54 pm »

Some Guy:
I guess you should experiment with longer shutter speeds? Also, why lose 2-3 stops with filtering the light? If you shoot in RAW, you can easily correct for this in Post!

Happy Flashing! ;-)
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #4 on: August 20, 2014, 12:19:07 pm »

Some Guy:
I guess you should experiment with longer shutter speeds?

That won't help! These bulbs are useless except for time exposures!
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #5 on: August 20, 2014, 12:57:07 pm »

Some Guy:
I guess you should experiment with longer shutter speeds? Also, why lose 2-3 stops with filtering the light? If you shoot in RAW, you can easily correct for this in Post!

Happy Flashing! ;-)

No, if he does not filter the flash at the source it will be of a different color temp than the rest of the light. This cannot be corrected! This is a waste of time!
« Last Edit: August 20, 2014, 01:09:51 pm by melchiorpavone »
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duane_bolland

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Re: Help with flashbulbs!
« Reply #6 on: August 20, 2014, 02:07:34 pm »

This is a waste of time!

It may be, but this thread made for good reading.  Thanks.
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Rhossydd

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Re: Help with flashbulbs!
« Reply #7 on: August 20, 2014, 03:03:19 pm »

No, if he does not filter the flash at the source it will be of a different color temp than the rest of the light.
This assumes there is any other light.
I've used flashbulbs a lot in the past for cave photography, no other light there.
In that situation not using any sort of filter to get the most light output makes complete sense.

Certainly shutter synchronization is probably the cause of the OP's problems in this case, you should be seeing GNs over maybe 200 or more depending on ISO http://www.flashbulbs.com/clearbulbs.htm

It's really not worth trying to use them for modern general flash work, electronic guns are easier, cheaper and more versatile and reliable for most use.

But flashbulbs certainly aren't rubbish or to be thrown away, there remain a small minority of photographers who can use these rare items to good purpose. If you haven't a pressing need for this sort of high output device, pop them on eBay so someone who really can utilise them can buy them from you.
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #8 on: August 20, 2014, 03:17:40 pm »

This assumes there is any other light.
I've used flashbulbs a lot in the past for cave photography, no other light there.
In that situation not using any sort of filter to get the most light output makes complete sense.

Certainly shutter synchronization is probably the cause of the OP's problems in this case, you should be seeing GNs over maybe 200 or more depending on ISO http://www.flashbulbs.com/clearbulbs.htm

It's really not worth trying to use them for modern general flash work, electronic guns are easier, cheaper and more versatile and reliable for most use.

But flashbulbs certainly aren't rubbish or to be thrown away, there remain a small minority of photographers who can use these rare items to good purpose. If you haven't a pressing need for this sort of high output device, pop them on eBay so someone who really can utilise them can buy them from you.

Well, yes, but he was not indicating he would be using them in isolation.

Sure, they may have value for cave photography, which is a species of time exposure, as I said. Other than that (time exposures), they are of no value, as modern cameras cannot be synchronized to them.

If you have an old Graflex they may come in handy though!

http://www.meggaflash.com/meggaflash-bulbs
« Last Edit: August 20, 2014, 03:36:44 pm by melchiorpavone »
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Rhossydd

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Re: Help with flashbulbs!
« Reply #9 on: August 20, 2014, 04:11:10 pm »

Sure, they may have value for cave photography,.....
Not just that. Photographing big industrial interiors is another case, as is after dark landscape and architectural photography.
Flashbulbs can deliver a huge amount light without needing expensive hardware or power supplies.
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Some Guy

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Re: Help with flashbulbs!
« Reply #10 on: August 20, 2014, 04:14:32 pm »

Update:

Okay, I got them (Wabash Press #40) to work with a Nikon D800E.  Problem with the Press #40 bulbs is they need to fire ahead of the Nikon shutter's lag which is around 43ms if the auto-focus is locked into manual mode.  The bulb's ignite around 5ms and max. burn peak is around 20-25 ms or so.  Nikon is a bit slow at 43ms so you will end up on the tail end of the bulb's burn curve (And underexposing maybe 3-4 stops) if you sync via their banana jack cable (Plus, you need the AF and metering 5 volt voltage to even get to the shutter trip signal as well.).

If I try and use the last flashbulb maker's in the world's bulbs (i.e. Meggaflash PF-330 @ $75 each out of Roger George in Hollywood, CA.) they need to lag behind the Nikon shutter's firing by almost 0.36 seconds or more before they hit maximum brightness.  The old Press #40 bulbs fire faster than the newer #33 series bulbs (Sylvania or Meggaflash) do and need to be fired ahead of the Nikon 43ms shutter lag.  The new Meggaflash bulbs that have a burn duration of almost 2 seconds long (Try that with an electronic flash!  It won't work with any of them!) need a different timing sequence.  I thought about using an electronic flash, but even if they are firing at 1/300 second each in full power, it would take 300 studio units in sequence to make for a one-second exposure verses an old flash bulb that can burn for 2 seconds, although it cost you $75 a shot too.  So compare 300 studio units to a few $75 bulbs (or half that on old eBay Sylvania FF-33 bulb stock) and examine the cost differential.

Anyway, the Press #40 bulbs are working now "leading" the Nikon shutter lag and agree with the flash meter since the shutter sync issue has been addressed and fixed via an external microprocessor and timing relays.  I have a GN=45 for what reflector I use with them and a Lee #201 CC filter for a 5,200K number.  The Megga's may get me up to around 4 times that GN due to their longer burn duration of 2 seconds.  However, it takes a microprocessor and relay set to do so for flash sync with the new digital cameras and some programming work, but it now works perfectly without high currents of the trigger capacitor for the bulb blowing out the camera's circuit boards since it is all relay controlled.  Results are a much higher GN than any electronic flash can provide.  One needs to use a color correction filter like some Lee #201 or #202 to balance them to daylight Kelvin though.  With the PF-330, my GN might hit 1,000 with the reflector and CC #202 filter.  No consumer electronic or studio flash can touch that.

And as one posted above, they do use them for caves and mines, fast moving water or waterfalls (Electronic flash results in a double-exposure at slow (water-blur) shutter speeds), as well as the high-speed auto crash cameras that run about 10,000 frames per second.  Electronic flash cannot do that, but the old bulb stuff still can - and it does, if you can sync it all up with digital.

SG
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #11 on: August 20, 2014, 04:18:31 pm »

Not just that. Photographing big industrial interiors is another case, as is after dark landscape and architectural photography.
Flashbulbs can deliver a huge amount light without needing expensive hardware or power supplies.


As I said, time exposures!

But they cannot be used as syncho-flash!
« Last Edit: August 20, 2014, 04:55:50 pm by melchiorpavone »
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #12 on: August 20, 2014, 04:28:24 pm »

Update:

Okay, I got them (Wabash Press #40) to work with a Nikon D800E.  Problem with the Press #40 bulbs is they need to fire ahead of the Nikon shutter's lag which is around 43ms if the auto-focus is locked into manual mode.  The bulb's ignite around 5ms and max. burn peak is around 20-25 ms or so.  Nikon is a bit slow at 43ms so you will end up on the tail end of the bulb's burn curve (And underexposing maybe 3-4 stops) if you sync via their banana jack cable (Plus, you need the AF and metering 5 volt voltage to even get to the shutter trip signal as well.).

If I try and use the last flashbulb maker's in the world's bulbs (i.e. Meggaflash PF-330 @ $75 each out of Roger George in Hollywood, CA.) they need to lag behind the Nikon shutter's firing by almost 0.36 seconds or more before they hit maximum brightness.


NO!!!! they need to fire ahead of the shutter! ALL flashbulbs take a long time after ignition to burn and reach peak brightness, and focal-plane bulbs burn longer after that, so the shutter has to be delayed, not the bulbs!

Quote
The old Press #40 bulbs fire faster than the newer #33 series bulbs (Sylvania or Meggaflash) do and need to be fired ahead of the Nikon 43ms shutter lag.

No! Your information is wrong. There is no shutter lag at all with X synch, which is the only kind incorporated into modern cameras.

Quote
The new Meggaflash bulbs that have a burn duration of almost 2 seconds long (Try that with an electronic flash!  It won't work with any of them!) need a different timing sequence.

What are you talking about? No flashbulb burns that long!

Quote
I thought about using an electronic flash, but even if they are firing at 1/300 second each in full power, it would take 300 studio units in sequence to make for a one-second exposure verses an old flash bulb that can burn for 2 seconds, although it cost you $75 a shot too.  So compare 300 studio units to a few $75 bulbs (or half that on old eBay Sylvania FF-33 bulb stock) and examine the cost differential.

This makes no sense at all. What are you talking about?

Quote
Anyway, the Press #40 bulbs are working now "leading" the Nikon shutter lag and agree with the flash meter since the shutter sync issue has been addressed and fixed via an external microprocessor and timing relays.  I have a GN=45 for what reflector I use with them and a Lee #201 CC filter for a 5,200K number.  The Megga's may get me up to around 4 times that GN due to their longer burn duration of 2 seconds.  However, it takes a microprocessor and relay set to do so for flash sync with the new digital cameras and some programming work, but it now works perfectly without high currents of the trigger capacitor for the bulb blowing out the camera's circuit boards since it is all relay controlled.  Results are a much higher GN than any electronic flash can provide.  One needs to use a color correction filter like some Lee #201 or #202 to balance them to daylight Kelvin though.  With the PF-330, my GN might hit 1,000 with the reflector and CC #202 filter.  No consumer electronic or studio flash can touch that.

And as one posted above, they do use them for caves and mines, fast moving water or waterfalls (Electronic flash results in a double-exposure at slow (water-blur) shutter speeds), as well as the high-speed auto crash cameras that run about 10,000 frames per second.  Electronic flash cannot do that, but the old bulb stuff still can - and it does, if you can sync it all up with digital.

SG

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Rhossydd

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Re: Help with flashbulbs!
« Reply #13 on: August 20, 2014, 04:44:28 pm »

What are you talking about? No flashbulb burns that long!
Well to the nearest decimal point two seconds burn time is correct. See :- http://www.meggaflash.com/meggaflash-bulbs/pf330-flashbulb
Quote
This makes no sense at all. What are you talking about?
Maybe you need to learn a little bit more about flashbulb technology yourself before being so dismissive.
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #14 on: August 20, 2014, 04:48:55 pm »

Well to the nearest decimal point two seconds burn time is correct. See :- http://www.meggaflash.com/meggaflash-bulbs/pf330-flashbulbMaybe you need to learn a little bit more about flashbulb technology yourself before being so dismissive.

I knew all about it in the old days.

The bulbs you mentioned (the Press 40s) are not like that. That's the type I thought we were discussing. You cannot use them as synchro-flash with the current type of cameras, which have only "X" synch.

The only way to use the Press 40 flashbulbs is with time exposures.
« Last Edit: August 20, 2014, 04:55:35 pm by melchiorpavone »
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Rhossydd

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Re: Help with flashbulbs!
« Reply #15 on: August 20, 2014, 04:59:05 pm »

I knew all about it in the old days...... That's the type I thought we were discussing.
Comment on what people write.
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #16 on: August 20, 2014, 05:00:35 pm »

Comment on what people write.

Sorry, I missed that detail.
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Some Guy

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Re: Help with flashbulbs!
« Reply #17 on: August 20, 2014, 05:42:04 pm »



NO!!!! they need to fire ahead of the shutter! ALL flashbulbs take a long time after ignition to burn and reach peak brightness, and focal-plane bulbs burn longer after that, so the shutter has to be delayed, not the bulbs!

No! Your information is wrong. There is no shutter lag at all with X synch, which is the only kind incorporated into modern cameras.

What are you talking about? No flashbulb burns that long!

This makes no sense at all. What are you talking about?


Wow!  You really need to look into the spec's of what I posted and pay attention.  I'm doing it now and proving my results.  Are you?  Your theory, and what happens in practice and use, do not mix.

Fact:
Nikon D800E shutter lag is 43ms without AF engaged.  If you engage AF, then maybe 250 ms or whatever variable time it takes for the lens to lock-on AF, but I am in manual mode to circumvent that.  So 43ms it is for the shutter lag number once into Manual mode.

If you saw the first curve I posted, it takes about 5ms for the #40 bulb to ignite, and then about 20ms to hit full burn.  Then goes dark in about 50ms.  If you use the Nikon remote via their 10 pin and their cord, the metering and AF signal activates the shutter first (and required too), and then the lag until the mirror flips out of the way and the shutter is fully open which occurs 43ms later.  Hence the flash bulb does need to lead the Nikon D800E shutter release using their cabling and not shoeing it all.

I am not using the hot shoe, nor their PC outlet as it might not take the amperage to fire the bulb with the 220uf trigger capacitor running off a 15 volt battery.  Don't know if a 220uf @ 15 volts as a short of the bulb's trigger capacitor will fry the camera's internals so it has been isolated via separate relays.  Been there already, and why I started this post.

I was getting severe underexposure as the bulb was firing on the tail-end of the shutter's lag timing.  Hence the flash meter and my trial GN test exposures did not match and images were underexposed - a lot.  It is now fixed via a microprocessor timing to fire the bulb "ahead" of the shutter release signal for the #40 bulbs.  I needed to re-program the microprocessor delay from the FF-33 or PF-330 bulbs ramp-up to maximum burn delay for the #40 bulbs, since they have a very long ramp up to maximum burn of about 400ms.  In short, I'm now tripping the shutter ahead of the bulb.  For the Meggaflash/Sylvania bulbs, the opposite occurs to fire the bulb far later than the shutter (or where I came from.).

The Meggaflash PF-330 specs are here:  http://www.meggaflash.com/meggaflash-bulbs/pf330-flashbulb  Notice the 400ms lag time to peak burn, way behind the Nikon 43ms lag, or subtract that from 400ms making the flash trigger at 357ms.  Plus notice the extreme duration burn time of almost "TWO SECONDS" once fired (Okay, 1.75ms is good enough.).  The Meggaflash PF-330 is a copy of the old discontinued Sylvania FF-33 bulbs that are a perfect spec's match.  Notice too the extreme output of 140,000 lumen seconds.

All this flash bulb control stuff needs to be done via a microprocessor now if ones use the Nikon 10 pin remote cable like the MC-30A, or their banana lead (MC-22) one.

Like I said, I'm doing it and now proving it to myself as well as the flash meter which now agrees with the theoretical guide numbers and the test photos.  I made the error of sync'ing it all up later (Prepared for the FF-33 bulbs) and got me here to ask.  Since then, I've learned I was in error and on the tail end of the #40 bulb burn and why the Press #40 bulbs must be fired "ahead" of the shutter lag in the Nikon via the cabling since they cable parallel off to a shutter trip relay as well as the flash bulb relay.  If the bulbs goes dark around 50ms after ignition, and the shutter lag is 43 ms, you got little to nothing like I had.

Luckily, the microprocessor control timer I am using (Radio Shack Uno and a Seed Relay Shield v2.0, fwiw.) allows me to set a fixed microsecond timing occurrence to either lead or lag the Nikon shutter relay to address it.  With the Meggaflash PF-330 or Sylvania FF-33 discontinued flashbulbs, it must occur long 'after' the shutter lag time to hit their peak burn.  With the faster Press #40 bulbs, the shutter relay lag of 43ms needs to get going 'ahead' of the flash relay before it trips the #40 as it only takes 5ms to get them going - else you got squat like I did prior.

Neat part of the Arduino Uno relay's circuit board is the LED's that are visible on it as to the relay's (both shutter and flash relays) operation.  The shutter relay trips ahead of the flash relay for the #40 bulbs.  The opposite occurs for the Meggaflash bulbs - and it is a much longer visible LED delay too.  You can actually tailor whatever bulbs you want in a digital camera, just it takes some timing control which I've also done - aside from my mistake of assuming the shutter lag matter on the Nikon compared to the Meggaflash/Sylvaniseries 33 curves and the older Wabash Press #40 ignition curves which are very different animals that got me here.

SG
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melchiorpavone

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Re: Help with flashbulbs!
« Reply #18 on: August 20, 2014, 05:49:41 pm »

Wow!  You really need to look into the spec's of what I posted and pay attention.  I'm doing it now and proving my results.  Are you?  Your theory, and what happens in practice and use, do not mix.

Fact:
Nikon D800E shutter lag is 43ms without AF engaged.  If you engage AF, then maybe 250 ms or whatever variable time it takes for the lens to lock-on AF, but I am in manual mode to circumvent that.  So 43ms it is for the shutter lag number once into Manual mode.

If you saw the first curve I posted, it takes about 5ms for the #40 bulb to ignite, and then about 20ms to hit full burn.  Then goes dark in about 50ms.  If you use the Nikon remote via their 10 pin and their cord, the metering and AF signal activates the shutter first (and required too), and then the lag until the mirror flips out of the way and the shutter is fully open which occurs 43ms later.  Hence the flash bulb does need to lead the Nikon D800E shutter release using their cabling and not shoeing it all.

I am not using the hot shoe, nor their PC outlet as it might not take the amperage to fire the bulb with the 220uf trigger capacitor running off a 15 volt battery.  Don't know if a 220uf @ 15 volts as a short of the bulb's trigger capacitor will fry the camera's internals so it has been isolated via separate relays.  Been there already, and why I started this post.

I was getting severe underexposure as the bulb was firing on the tail-end of the shutter's lag timing.

No, the reverse! The "delay" is counted from the sending of the electric signal, not autofocus! The shutter is going off before the flash bulb reaches its peak brightness, not after! Autofocus has nothing to do with it! The connection to fire the flash comes only after autofocus is attained!

Quote

Hence the flash meter and my trial GN test exposures did not match and images were underexposed - a lot.

No! no! no!

Quote
It is now fixed via a microprocessor timing to fire the bulb "ahead" of the shutter release signal for the #40 bulbs.

No, it won't help! The flash burns too quickly and does not provide light for the entire length of the exposure with a focal-plane shutter!

Quote
I needed to re-program the microprocessor delay from the FF-33 or PF-330 bulbs ramp-up to maximum burn delay for the #40 bulbs, since they have a very long ramp up to maximum burn of about 400ms.  In short, I'm now tripping the shutter ahead of the bulb.  For the Meggaflash/Sylvania bulbs, the opposite occurs to fire the bulb far later than the shutter (or where I came from.).

The Meggaflash PF-330 specs are here:  http://www.meggaflash.com/meggaflash-bulbs/pf330-flashbulb  Notice the 400ms lag time to peak burn, way behind the Nikon 43ms lag, or subtract that from 400ms making the flash trigger at 357ms.  Plus notice the extreme duration burn time of almost "TWO SECONDS" once fired (Okay, 1.75ms is good enough.).  The Meggaflash PF-330 is a copy of the old discontinued Sylvania FF-33 bulbs that are a perfect spec's match.  Notice too the extreme output of 140,000 lumen seconds.

All this flash bulb control stuff needs to be done via a microprocessor now if ones use the Nikon 10 pin remote cable like the MC-30A, or their banana lead (MC-22) one.

Like I said, I'm doing it and now proving it to myself as well as the flash meter which now agrees with the theoretical guide numbers and the test photos.  I made the error of sync'ing it all up later (Prepared for the FF-33 bulbs) and got me here to ask.  Since then, I've learned I was in error and on the tail end of the #40 bulb burn and why the Press #40 bulbs must be fired "ahead" of the shutter lag in the Nikon via the cabling since they cable parallel off to a shutter trip relay as well as the flash bulb relay.  If the bulbs goes dark around 50ms after ignition, and the shutter lag is 43 ms, you got little to nothing like I had.

Luckily, the microprocessor control timer I am using (Radio Shack Uno and a Seed Relay Shield v2.0, fwiw.) allows me to set a fixed microsecond timing occurrence to either lead or lag the Nikon shutter relay to address it.  With the Meggaflash PF-330 or Sylvania FF-33 discontinued flashbulbs, it must occur long 'after' the shutter lag time to hit their peak burn.  With the faster Press #40 bulbs, the shutter relay lag of 43ms needs to get going 'ahead' of the flash relay before it trips the #40 as it only takes 5ms to get them going - else you got squat like I did prior.

Neat part of the Arduino Uno relay's circuit board is the LED's that are visible on it as to the relay's (both shutter and flash relays) operation.  The shutter relay trips ahead of the flash relay for the #40 bulbs.  The opposite occurs for the Meggaflash bulbs - and it is a much longer visible LED delay too.  You can actually tailor whatever bulbs you want in a digital camera, just it takes some timing control which I've also done - aside from my mistake of assuming the shutter lag matter on the Nikon compared to the Meggaflash/Sylvaniseries 33 curves and the older Wabash Press #40 ignition curves which are very different animals that got me here.

SG


You don't understand at all, after I carefully explained this all to you? How can that be?

Read this:

http://camerapedia.wikia.com/wiki/Flash_sync

http://photography.tutsplus.com/articles/a-brief-history-of-photographic-flash--photo-4249

http://books.google.com/books?id=h4LOAwAAQBAJ&pg=PA210&lpg=PA210&dq=flash+synchronization+flashbulbs&source=bl&ots=LkuKsINpWh&sig=qRV9_WbiPN6UvHgdjfDbs7PE-Fc&hl=en&sa=X&ei=Ixr1U4PdKMGnyATLyIJ4&ved=0CGQQ6AEwCA#v=onepage&q=flash%20synchronization%20flashbulbs&f=false

http://photography-on-the.net/forum/archive/index.php/t-268636.html

Once again, you cannot synch Press 40 bulbs with a modern focal-plane shutter! It is not possible!
« Last Edit: August 20, 2014, 06:05:15 pm by melchiorpavone »
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Some Guy

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Re: Help with flashbulbs!
« Reply #19 on: August 20, 2014, 06:51:25 pm »

No, the reverse! The "delay" is counted from the sending of the electric signal, not autofocus! The shutter is going off before the flash bulb reaches its peak brightness, not after! Autofocus has nothing to do with it! The connection to fire the flash comes only after autofocus is attained!

No! no! no!

No, it won't help! The flash burns too quickly and does not provide light for the entire length of the exposure with a focal-plane shutter!

You don't understand at all, after I carefully explained this all to you? How can that be?

Read this:

http://camerapedia.wikia.com/wiki/Flash_sync

http://photography.tutsplus.com/articles/a-brief-history-of-photographic-flash--photo-4249

http://books.google.com/books?id=h4LOAwAAQBAJ&pg=PA210&lpg=PA210&dq=flash+synchronization+flashbulbs&source=bl&ots=LkuKsINpWh&sig=qRV9_WbiPN6UvHgdjfDbs7PE-Fc&hl=en&sa=X&ei=Ixr1U4PdKMGnyATLyIJ4&ved=0CGQQ6AEwCA#v=onepage&q=flash%20synchronization%20flashbulbs&f=false

http://photography-on-the.net/forum/archive/index.php/t-268636.html

Once again, you cannot synch Press 40 bulbs with a modern focal-plane shutter! It is not possible!

No, the reverse! The "delay" is counted from the sending of the electric signal, not autofocus! The shutter is going off before the flash bulb reaches its peak brightness, not after! Autofocus has nothing to do with it!

No! no! no!

No, it won't help! The flash burns too quickly and does not provide light for the entire length of the exposure with a focal-plane shutter!

You don't understand at all, after I carefully explained this all to you? How can that be?

Read this:

http://camerapedia.wikia.com/wiki/Flash_sync

http://photography.tutsplus.com/articles/a-brief-history-of-photographic-flash--photo-4249

Your theory, and mine in practice do not mix.  I'm doing it now.  If I follow your instructions, it will not work.

Scenario:
One concurrent signal going to two relays off the MC-30A remote:  One for shutter trip relay (or internal body shutter release switch).  The other goes to a flash relay or switch (external hot shoe for the screw-in flash bulbs.  Take your pick on bulbs mentioned, but they do matter as to timing.).  The release signal of SW2 within the Nikon remote hits both relays at same time.  (AF/Metering is ignored and Off for the most part, and all subsequent is in Manual Focus and Metering.  Only reason it is mentioned is that it is pre-requisite:  AF & Metering is off SW1 in the Nikon remote, and feeds to the shutter SW2 in the remote.  Been through mess that already.).

Check?

Now...

The Nikon shutter relay, once it gets the trip signal from the MC-30A remote "delays" the shutter for 43ms (Has to get the mirror out of the way and open the blades.).  Meanwhile, the flash relay has already tripped and the bulb has already fired for its 50ms burn duration.  So you only acquired maybe 7ms of the bulb's total burn period (My underexposure, verses what my meter was telling me is why I got here asking.).

Now the shutter is finally opened at 43ms, but the 50ms burn of the bulb is now going out (On the tail end of its burn) since it fired along with the shutter signal trip at the same time.  So I ended up with a bad underexposure compared to what my meter was telling me by 3-4 stops.

This is for the quicker firing #40 bulbs too.

Now the opposite occurs for the PF-330 bulbs that take 400ms to get up to maximum burn.  Nikon's shutter (lag) relay opens in 43ms, and flash relay has also tripped prior, but the burn is still ramping up to peak burn in another 357ms beyond the slow Nikon shutter lag.

Pretty simple?

As to the metering or AF, that is Off and in Manual focus only due to AF searching and slowness prior lock-on and allowing the shutter release firing signal which is a big variable.  The Nikon uses 5 volts off the AF/Metering pin in the 10 pin to feed the remote's shutter release SW2 in the MC-30A.  You need to use that AF/Metering signal else the shutter will not trip the way Nikon designed it.  Been there.

I already built the circuit with the Arduino microprocessor and relay board and it now works via my timing.  Yours will not work.  Trust me.  Yours (in theory when I began the flash bulb timing mess) is what got me into this sync matter and why it will not work via the Nikon 10 pin connector.  It will lead to bad under-exposure with the Press #40 like I got, but the 33 series "may work" but you have prolonged the shutter and they are much slower to ramp-up and the slow shutter lag is masked. The bulbs differ in ignition timing and their maximum burn, and the Nikon's shutter lag (Which varies between models too!) is another matter.

Note too that this is not off the shutter's internal switches or control circuit as it may burn out depending on the flash bulb circuit's current flow as it is mostly a dead short when the flash relay closes to get the bulb to fire (aka, Much like Honeywell's Tilt-a-Might flash holder circuitry which might hit a peak of 2-3 amps once triggered.).

Reality is that my Nikon would need, actually it does need, two separate timing signals for the shutter relay:  Fire it prior to the flash relay for the Press #40 bulbs, or fire it much later for the Meggaflash/Sylvania series 33 bulbs.

You actually can move the burn cycle of any old flash bulb to either "lead" or "follow" the shutter using two relays controlled by a microprocessor as I am now doing:  One relay controls the shutter; Second relay for the lamp.  A delay time can be assigned to either to suit the bulb's ignition to maximum burn time.

As I mentioned, I'm doing it now.

SG
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