Getting into flashbulb lighting and looking for some help

[Helge]

Note to those who may not know: The GN table images, above, are for TUNGSTEN film speeds. Daylight film speeds may differ. Also, the tables that reference fim brands/types are likely not the same speed as the same film/type made today. So don't forget to factor in all of the changes between the film of the flashbulb era and today; check your GN calculations carefully.

“b” bulbs are, if any, only a smidgen slower than the non-blue ones.
That much is evident from the packs data sheets, among the one I posted above.
It also evidently works for when the bulb is inserted in the special blue shield Polaroid flash.

But true, as opposed to xenon flash, bulbs has a climbing (smooth) spectrum that extents far into infrared with very good output.
The blue coating is quite transparent to IR.
Aviphot film, and other IR sensitive film sings with bulbs, with or without IR filter.

 

[AgX]

Note to those who may not know: The GN table images, above, are for TUNGSTEN film speeds.

But the bulbs were bare, thus they fit very well.

 

[AgX]

“b” bulbs are, if any, only a smidgen slower than the non-blue ones.

25% less emission (Philips data)

But for speed of course the spectral sensitivity of the film must be taken into account.

 

[BrianShaw]

But for speed of course the spectral sensitivity of the film must be taken into account.

That was my only point about TUNGSTEN film speeds. It has nothing to do with the color of the bulb as insinuated in post #27. In this discussion, we don't know what film was being used, although one can assume that it was B&W since a clear bulb was used.

The difference between tungsten and daylight film speeds is generally slight so it doesn't make a huge difference. As I'm sure that you will agree, even slight it could be one of many valid considerations when trying to adapt old data guides to modern film.

A few random examples:

• KODAK PLUS-X Reversal film, 7276. Daylight, EI 50, Tungsten, EI 40 B&W.
• KODAK TRI-X Reversal film, 7278. Daylight, EI 200, Tungsten, EI 160 B&W.
• PLUS-X Panchromatic Negative film, 4231 35mm. Later changed to 5231. Daylight, EI 80, Tungsten, EI 64.
• EASTMAN RP Negative film, 7229. Daylight, EI 250. Tungsten, EI 200.
• EASTMAN XT-Pan Negative film, 5220 Daylight, EI 25. Tungsten, EI 20.
• etc

 

[Helge]

25% less emission (Philips data)

But for speed of course the spectral sensitivity of the film must be taken into account.

Where is that data?
I have data too (web and packs) but it’s very ambiguous because the split in ASA is different, and some of the packs are before the ASA/ISO adjustment.
Doing a bit of math the speeds are very close though.
Osram bulbs are the same speed.

 

[BrianShaw]

 

[Helge]

That was my only point about TUNGSTEN film speeds. It has nothing to do with the color of the bulb as insinuated in post #27. In this discussion, we don't know what film was being used, although one can assume that it was B&W since a clear bulb was used.

The difference between tungsten and daylight film speeds is generally slight so it doesn't make a huge difference. As I'm sure that you will agree, even slight it could be one of many valid considerations when trying to adapt old data guides to modern film.

A few random examples:

• KODAK PLUS-X Reversal film, 7276. Daylight, EI 50, Tungsten, EI 40 B&W.
• KODAK TRI-X Reversal film, 7278. Daylight, EI 200, Tungsten, EI 160 B&W.
• PLUS-X Panchromatic Negative film, 4231 35mm. Later changed to 5231. Daylight, EI 80, Tungsten, EI 64.
• EASTMAN RP Negative film, 7229. Daylight, EI 250. Tungsten, EI 200.
• EASTMAN XT-Pan Negative film, 5220 Daylight, EI 25. Tungsten, EI 20.
• etc

It does, since the “b” bulbs are tuned for daylight film.

 

[Helge]

View attachment 306769

So according to this the output is nigh on halved. Can’t be right. The filtering doesn’t look that strong.
Fortunately it’s relatively easy to remove the blue plastic film with a sharp knife should you want it.

 

[BrianShaw]

So according to this the output is nigh on halved. Can’t be right. The filtering doesn’t look that strong.
Fortunately it’s relatively easy to remove the film with a sharp knife should you want it.

If you doubt the data, bring some different data to the table. About 1 stop difference has been my experience as a flash bulb user.

 

[Helge]

The speed of the film, daylight and/or tungsten, is independent of the color of the bulb. You are talking about matching the light source to the film type. I am talking about the speed rating of the film. Different discussions.

The speed rating with blue coating is close (according to my sources). And the coating is meant to accommodate daylight film.

If you doubt the data, bring some different data to the table. About 1 stop difference has been my experience as a flash bulb user.

Will try to find something tomorrow.
We need to get to the bottom of this! ;-)

 

[Down Under]

Most of us discarded our flash guns and flash bulbs along with button-up boots and wing collars. If you have either, sell them on Ebay for a small fortune, and go on a world cruise with the proceeds...

Flash in this day and age is, as I see it, 99.999% electronic. You can do so much more with it. Those old Graphic/Graflex flash guns used bulbs the size of Edison light globes, and they (the former) tended to explode at times, with dramatic responses from your (live) subjects. They nowadays also cost the price of a small car. They are now entirely museum pieces, not easily used photo accessories.

With a little effort with electronic flash you can quite easily duplicate the Vampire White face gloss and Scared Rabbit (aka Deer In The Headlights) Look, like in those 1940s news photographs. (= Weegee.)

 

[Helge]

Most of us discarded our flash guns and flash bulbs along with button-up boots and wing collars. If you have either, sell them on Ebay for a small fortune, and go on a world cruise with the proceeds...

Flash in this day and age is, as I see it, 99.999% electronic. You can do so much more with it. Those old Graphic/Graflex flash guns used bulbs the size of Edison light globes, and they (the former) tended to explode at times, with dramatic responses from your (live) subjects. They nowadays also cost the price of a small car. They are now entirely museum pieces, not easily used photo accessories.

With a little effort with electronic flash you can quite easily duplicate the Vampire White face gloss and Scared Rabbit (aka Deer In The Headlights) Look, like in those 1940s news photographs. (= Weegee.)

That’s right Oz! Using bulbs is stupid. Stop it right now. ;-)

 

[AgX]

Fortunately it’s relatively easy to remove the blue plastic film with a sharp knife should you want it.

But by this you also remove the safety feature of the small, more modern bulbs.

 

[Helge]

But by this you also remove the safety feature of the small, more modern bulbs.

Always use a shield.
Plus I’ve only once had a bulb send out debris, and that only into the upturned dish.

 

[AgX]

So far I experienced or came across no AG bulb where any morsels have left, in spite of the glass cracked.

Many bulb flashes did not come with a shield. And I have not yet found any reference to shielding in old texts. Some flash manufacturers added one, others not.



But for safety reason I advise not to use any bulb with a pink indicator and use bulbs without an indicator only behind a shield.


From my own experience I consider halogen lamps much more dangerous though, but this I may explain in a thread of its own...

 

[Helge]

Dug out some M3s. Thanks to Laser for the “B” variety.

These are pretty contemporary, but again the rating spans are written out differently.

Look at the 25 on the B and the 20-32 on the clear though.
These are reasonable close. With a tiny advantage to the clear.

The speed difference is 18.18 percent. (Not accounting for the tiny advantage in ratings to clear.)

Edit. Also:

Seems even Philips couldn't see much difference.
The diagonal disclaimer on the box is "new revised film speeds" in Swedish.

 

[BrianShaw]

It does, since the “b” bulbs are tuned for daylight film.

Of course they are… blue filtered to accommodate tungsten light with daylight-balanced film; we all agree on that.

We’re talking past each other, it seems. I’m talking about FILM speed (ASA/ISO). You keep talking about BULB speed (GN or other measure of light output).

My point is rather simple. The tables generally show tungsten film speed. Modern film is identified with DAYLIGHT SPEED rather than identifying both daylight and tungsten speeds as they did in the past and examples shown in my earlier post, above.

 

[Helge]

Of course they are… blue filtered to accommodate tungsten light with daylight-balanced film; we all agree on that.

We’re talking past each other, it seems. I’m talking about FILM speed (ASA/ISO). You keep talking about BULB speed (GN or other measure of light output).

My point is rather simple. The tables generally show tungsten film speed. Modern film is identified with DAYLIGHT SPEED rather than identifying both daylight and tungsten speeds as they did in the past and examples shown in my earlier post, above.

Ok, it’s not as simple to get what I mean I guess.
The bulb is already filtered for the loss in speed incurred by the film.
It’s already part of the table, if we are talking “B” bulbs.
There is no (or very small) additional loss.

Bulbs are natively/fundamentally warmer, while xenon is colder (closer to midday light).

 

[BrianShaw]

Deep sigh. This really doesn't help @backseatpilot at all... talking nits so I'll leave the conversation. Bye.

 

[Patrick Robert James]

I've never used flash bulbs, except as a joke in a light fixture, but you need to think of exposure differently when dealing with flash, whether it is bulbs or electronic. The aperture is what gives the correct exposure with the flash output. The shutter speed determines the ambient exposure. The only reason to shoot with a flash at 1/500 is if you are outside and that is your only option. Of course with bulb flash the shutter speed is a factor, but the aperture/shutter speed effect is the general rule.

 

[Helge]

Deep sigh. This really doesn't help @backseatpilot at all... talking nits so I'll leave the conversation. Bye.

It’s doesn’t? Then why did you go on?
I’d think so, and his main questions was addressed as well as possible in the first ten or so posts.

 

[Helge]

I've never used flash bulbs, except as a joke in a light fixture, but you need to think of exposure differently when dealing with flash, whether it is bulbs or electronic. The aperture is what gives the correct exposure with the flash output. The shutter speed determines the ambient exposure. The only reason to shoot with a flash at 1/500 is if you are outside and that is your only option. Of course with bulb flash the shutter speed is a factor, but the aperture/shutter speed effect is the general rule.

Not correct for bulbs. There you can control flash strength with shutter speed too. And ambient fill will always be about the same until you get below 1/30 or so.

That’s both a strength and a drawback with bulbs.

Bulbs remote radio triggered is where they really start to sing.

 

[MattKing]

Not correct for bulbs. There you can control flash strength with shutter speed too.

Technically speaking, you can't control flash strength with shutter speed, but can elect to use only a portion of the light energy put out by the flash by choosing a faster shutter speed/shorter exposure time than the duration of light output.

 

[Patrick Robert James]

Not correct for bulbs. There you can control flash strength with shutter speed too. And ambient fill will always be about the same until you get below 1/30 or so.

That’s both a strength and a drawback with bulbs.

Bulbs remote radio triggered is where they really start to sing.

Keep reading.... I'll chalk up your correction to english as your second language because that is pretty much exactly what I wrote.

 

[Helge]

Technically speaking, you can't control flash strength with shutter speed, but can elect to use only a portion of the light energy put out by the flash by choosing a faster shutter speed/shorter exposure time than the duration of light output.

True. And you can bounce it, snoot it, filter it, naked bulb it etc.
Common to all of the attenuating techniques is that it’s hard to vary the ratio of ambient to flash over or during the exposure (as in a curve or a step), unless you go below 1/30th.