Strobe eqivalent for No.5 flashbulb

[Donald Qualls]

Actually, a strobe on the Speed isn't limited at all -- I can use any speed I like with the front shutter, if it has X synch, and can't use the rear shutter at all (at least on my Anny model, the only slit that uncovers the whole film plane at once is T, and it won't run through, only stops at full open and has to be released again to close). Since I doubt I'll ever see a 6 or 26 bulb, I'm limited to front shutter for flash anyway.

I'm actually looking for good bayonet-to-M and/or M-to-AG adapters for a decent price. The ones I've seen on eBay when I had money always went for $20 and up, and the ones I've seen that went for a reasonable price (like the Dutch auction of a whole dealer card of them) came when I was broke. I've got a bunch of M2 and M3 bulbs, and an even bigger bunch of AG-1s (a couple hundred of those).

I've never seen different guide numbers for different reflector positions, and I've got several "new" packages of #5, M2, M3, and AG-1 bulbs around. The P40s don't have guide number information on the individual bulb sleeves, and I don't have a flash that would work with the Speed that can use them anyway. Most of the bulbs you find these days are from the last year or two of production, when the factories were just starting to figure out that strobes were eating their lunch, and by then the Speed was pretty much out of the flashbulb picture, with professional having converted to electronic flash years earlier.

 

[pandino]

Donald,
You're correct, the packages don't have GN's for tele settings, but do have info for shutter speeds and sometimes adjustments for reflector sizes. GN's for tele setting could be arrived at by calculation (with known coverage angles) or empirically.

I'm sure there are still hundred's of thousands of bulbs out there, though people like us are hoarding most of them. I have a case each of 25's, 26's and M3's. If you want them, you'll need to pry them from my cold dead hands...if there are any left by then.

 

[DBP]

I'm sure there are still hundred's of thousands of bulbs out there, though people like us are hoarding most of them. I have a case each of 25's, 26's and M3's. If you want them, you'll need to pry them from my cold dead hands...if there are any left by then.

I'm still holding on to about two dozen No 22s for the night that I have to take action shots on a large field in the dark. Can't use them with the 1944 Anny Speed Graphic, oddly enough, as some prior owner re-synched it for electronic flash. (Went through a dozen No 5s and sheets of film before I figured that out.)

 

[Dan Fromm]

Dan, I don't see how a 1/200 flash is that big a deal if you're getting power comparable to a big magnesium bulb. <snip>.

Donald, its a huge deal when shooting hummingbirds. I've tried to deal with the duration by placing the flash close to the subjects and running it on TTL auto. Still pretty iffy.

Its also a huge deal when the object is to overpower ambient, flash to subject distance is "far," and I'm shooting with a 35 mm SLR, max sync speed 1/250.

 

[Lachlan Young]

Donald, its a huge deal when shooting hummingbirds. I've tried to deal with the duration by placing the flash close to the subjects and running it on TTL auto. Still pretty iffy.

Its also a huge deal when the object is to overpower ambient, flash to subject distance is "far," and I'm shooting with a 35 mm SLR, max sync speed 1/250.

Wouldn't you just cook them with a big bulb flash?

Lachlan

 

[David A. Goldfarb]

Things like hummingbirds and Lois Greenfield-style dancers in flight are pretty specialized cases of high-speed strobe photography, for which flashbulbs wouldn't really apply. The key there is to use more strobe heads (dancers) or portable flash units (hummers) at low power for short flash durations.

 

[Dan Fromm]

Things like hummingbirds and Lois Greenfield-style dancers in flight are pretty specialized cases of high-speed strobe photography, for which flashbulbs wouldn't really apply. The key there is to use more strobe heads (dancers) or portable flash units (hummers) at low power for short flash durations.

David, I know what I should have done. Did the best I could with what I had. Should have used the longer lens I don't have or stood closer to the birds. The flash I used -- Agfatronic 643 CS -- supports auto TTL and I took advantage of that; as I used it I was getting flash duration much shorter than 1/200.

Cheers,

Dan

 

[Dan Fromm]

Wouldn't you just cook them with a big bulb flash?

Lachlan

Cook 'em? I dunno. But I wasn't using bulb, its not appropriate. I was using a modern SCA 300 flash with flash output/duration controlled by my more or less modern Nikon.

I initially mentioned the flash, an Agfa Agfatronic 643 CS, because its full power output is in the range you asked about.

Thread drift is wonderful, eh?

 

[Donald Qualls]

Donald, its a huge deal when shooting hummingbirds. I've tried to deal with the duration by placing the flash close to the subjects and running it on TTL auto. Still pretty iffy.

Its also a huge deal when the object is to overpower ambient, flash to subject distance is "far," and I'm shooting with a 35 mm SLR, max sync speed 1/250.

Even in those situations, though, a bulb would be worse -- to get the full GN from a bulb, you need a shutter of 1/30 or slower (really, 1/15 for most M type bulbs -- 20 ms to peak and burn time of 25 ms or so), though they can be used at reduced GN at shutter speeds up to 1/200 or 1/250.

And a bulb wouldn't synch with your SLR unless you use a much slower shutter; you need to stay open at least long enough for the bulb to ignite and peak, preferably for about 80% of the burn (to get down below 1/4 power) or you'll have uneven exposure from the second curtain cutting off rapidly weakening light (well, a shutter with X synch to 250 probably wouldn't produce enough of this to notice). That's getting down to 1/30 or 1/15 -- which is what most bulbs call out as the slowest X synch speed to use anyway.

Sounds like what you really need for those hummingbirds is a bunch of smaller flashes, so you get the shorter burn time, and just add units until you have the power you need.

Edit: Sigh. And if I'd read the second page, I'd have seen two other folks had already said pretty much the same thing relative to the hummingbirds...

 

[Lachlan Young]

And a bulb wouldn't synch with your SLR unless you use a much slower shutter; you need to stay open at least long enough for the bulb to ignite and peak, preferably for about 80% of the burn (to get down below 1/4 power) or you'll have uneven exposure from the second curtain cutting off rapidly weakening light (well, a shutter with X synch to 250 probably wouldn't produce enough of this to notice). That's getting down to 1/30 or 1/15 -- which is what most bulbs call out as the slowest X synch speed to use anyway.

I don't know how old your cameras are but I know that my 25-30 year old OM1n cameras will synch all the way to 1/1000s with FP bulbs - if you can find them!

Hope this helps,

Lachlan

 

[Christiaan Phleger]

My Rollei 6008i syncs strobes at 1/1000 with the PQS lenses, add a few dialled down small strobes and you'd freeze the hummingbirds alright.

 

[Donald Qualls]

I don't know how old your cameras are but I know that my 25-30 year old OM1n cameras will synch all the way to 1/1000s with FP bulbs - if you can find them!

Hope this helps,

Lachlan

FP bulbs have a burn time designed to permit use with the focal plane shutters in the 1930s versions of Speed Graphic, Soho Reflex, Graflex, and other similar cameras. My pre-War Anniversary model has a total shutter travel time of about 1/8 second or a little slower, depending on the slit selected and tension setting (1/10 is the slowest timed speed, and it's about a half coverage slit), and an FP bulb must maintain a nearly flat light curve for at least this long after a predictable and standardized ignition time. Any speed you like in a smaller FP shutter (like the ones in medium format and miniature camers) will easily synch with these bulbs if the camera has an FP sync output (many modern cameras, from the post-flashbulb era, don't).

However, I was talking about X synch and type M bulbs, not FP synch with FP type bulbs.