what's the solenoid do?

[Frank Petronio]

Just wondering what the solenoid on the Speed/Crown Graphic shutter assembly does? All that schooling and I still don't know what a solenoid is for...

[CXC]

According to Google define:solenoid

A coil of wire that is long compared to its diameter, through which a current will flow and produce a magnetic flux to push or pull a rod (called an armature).

[Gem Singer]

Hi Frank,

Apply an electric current to a solenoid, and the plunger in the solenoid moves forward and trips the shutter. An electrically operated finger that can be adjusted to trip the sutter at the exact instant when the flash bulb is giving off it's maximum intensity. That was the method we used to syncronize our flash guns on our Speed Graphics back in the"good old days".

[Frank Petronio]

When I saw the recent movie "The Aviator" (Howard Hughes), the press photographers were throwing their used flashbulbs down on the ground and Howard's feet were crushing them as he walked the red carpet to a movie opening. Did you old timers really have to swap bulbs that fast? Looks like you only got one chance to get the shot... (at least it was on 4x5).

Weren't the flashbulbs hot? And didn't all that broken glass cut people up?

[Gem Singer]

Frank,

Hell yes, those flashbulbs were hot after they were fired off! I burned holes in a several sportcoat pockets (We had to shoot fast, and we weren't allowed to pop the spent bulbs out onto the floor at weddings and bar mitzvahs). Great motivation for switching to the (reusable) electronic flash guns that were introduced soon afterwards.

The flashbulbs that we used were coated with a plastic material that prevented them from shattering. However, the earlier bulbs (shown in the movie) didn't have that coating. It was a very realistic scene.

I thought the "Aviator" was a great movie. Saw it on New Years Eve. It deserves to win the Academy Award. I also saw "Ray". It's going to be a close race between those two movies.

[Robert McClure]

Hello Eugene!

I, for one, would be very curious to hear some of the details of what on earth you were doing when you were firing off flash bulbs and toting around a Speed Graphic. Newspaper work, freelance, or what? BTW, was it true that the 4x5 format fit nicely (at 100% of size) into two newspaper columns? Looks like the 4" dimension covers just right.

Regards

[Andy Eads]

While in high school photographing a basketball game, I had a new flash with a sticky socket. I laid it on my knee and pushed a Press 25 bulb in with thumb and two fingers. As I was pushing, the poorly placed open flash button was depressed by a fold in my pants. Suddenly I saw a great light and felt searing pain. I sat there with my back to the crowd crying softly wanting only for the pain to stop. I hope this answers your question about solenoids. ; )

[Gem Singer]

Hi Robert,

I was eighteen years old (1948), just starting college as a photojournalism major. I worked for the school's daily newspaper and the monthly humor magazine. Toted a 4X5 Speed Graphic that formerly belonged to a newspaper photographer in Detroit, Mich. (entire outfit packed into a large, heavy weight fiber camera case). The campus was very large and I was not. It soon became a tough job. Cars weren't allowed on campus, and I didn't own a car, anyhow. So, I solved the problem by purchasing a smaller second camera, a well- used older model Rolleiflex TLR, that was much easier to tote around. I was able to utilize the same large "potato masher" flashgun on both cameras.

I used the Speed Graphic mostly for portraits and group shots indoors. A few years later, I traded it for a new Rollei TLR. Never regretted doing that. I worked with various Rolleis for the next thirty years. In 1979, at almost fifty years of age, I sold my last Rollei and went back to doing large format, fine art photography with a 4X5 view camera.

There were many opportunities to shoot weddings, fraternity and sorority parties, and publicity photos with both cameras during those college days. I was having a great time, but not making any money. Then, as I began my third year of college, Uncle Sam decided that he wanted me. But, that's a whole other story.

Almost all of our work for publication was printed on single weight glossy 8X10 paper. I submitted the prints to the editors, and the printers took over from there. The editors would only accept contact prints when they had a short deadline to meet. I once had an entire centerfold in the magazine that was made directly from my 2 1/4 proof sheets from the 12 exposure Rollei negatives.

Now, lets all sing: "Those where the days my friend. We thought they 'd never end------"

[Jim Rice]

Back to the question at hand, it's for syncing to flashbulbs of course. God, I feel old.

[Ralph Barker]

Flash bulbs might be hot after firing, but they were a big improvement over measuring out flash powder into the tray - especially if you had a cigar in your mouth. ;-)

[Alec Jones]

Sorry Eugene, but you've got it backward. The Graflex solenoid PULLS, not PUSHES the plunger. It was used to sync the peak of flash bulbs flash for shutters w/o proper internal shutter sync for that purpose.

For modern use, the solenoid is still very useful. I use mine as an electronic shutter release. It works better than the internal cable release in a Pacemaker Speed or Crown.

And I use it for electronic flash too. The solenoid is used simply to trip the shutter. The sync is accomplished via a cord from the shutter's sync outlet to the flash. I use a Vivitar 283 mounted on top of the battery case [instead of the flash reflector]. Works great. Paramount will make you a Vivitar to dual post cord.

[Kevin M Bourque]

Yep, it pulls, not pushes. We used to call it a "solenoid sucking coil" back in high school electricity class. All us fiteen year-olds couldn't get enough of that....."hey, it's a solenoid sucking coil....smirk, smirk".

[mark anderson]

besides flash sinc its for taking pictures of pa'trige.

flash back (pun intended) to high scool, 1976

having an intrest in photography and nature, and lacking telephoto lens i mentioned wanting to take a photo of a pa'trige drumming (a mating ritual) to a friend of my farter. Jack Swedberg was kind enough to find a drumming log out behind my house. With the help of a short peice of speaker wire some aluminum foil and that soliniod i got a great shot on 2 1/4 x 3 1/4 kodacrome
(mm wasn't invented back then)

i have often wonderd why no one has come up with a similar device conected to a cable release and market it sucsesfully as a remote firing device

[Gem Singer]

Alec,

You're correct. A solenoid does PULL to fire the shutter. At least I got the shutter firing part correct. Please excuse my" senior moment". As usual, you certainly are a SMART Alec.

[robert_4927]

I have an old 1956 rollieflex 3.5 that i just can't seem to part with. ( hey everyone needs a point and shoot camera) I still use the old bulb flash with it with some stunning results. A lot of fun to play with.

[Gene Crumpler]

Eugene;

You really are an old fart. I remember when Tri-X first came out in 1954. I tired it in 35mm and never liked it. About once every 10 years, I try Txi-x and still don't like it. I messed up some other wise nice pictures of my granddaughter's birthday when a friend gave me several rolls of 220 pro tri-x. Even the hasselblad format didn't help with the grain. These days I use digital for family.

I miss Tech Pan :>(

[Dennis Mollura]

How is the solenoid connected to the flashgun? How is current applied to the solenoid? I don't see connecting points.

[W K Longcor]

How is the solenoid connected to the flashgun? I don't see a connecting point.

Most of the big flash "guns" had sockets in the battery tube that look kind of like the slots in a standard household electrical outlet. HH plug end of a sync cord goes there -- the graphic solinoids had a bi-post connector. Push button on flash unit -- electrical current sent through cord to solinoid. CLICK!:eek: OH! God, I'm feeling OLD!

[Dennis Mollura]

So the tripping current enters the solenoid through the lens tripping lever, right?

[W K Longcor]

So the tripping current enters the solenoid through the lens tripping lever, right?

No, the current enters solinoid throught the bi-post connector. The solinoid plunger moves, pulling the little hinged lever that usually has a wire "loop" at the end. The loop is hooked around the shutter trip lever and gives it a tug. One problem that nobody else has mentioned. If you did not cock the shutter -- you could still fire the flash bulb and activate the solinoid. So, you could get a click sound and a flash -- but NOT fire the camera and not expose any film! OOOpppss!

[Dennis Mollura]

No, the current enters solinoid throught the bi-post connector. The solinoid plunger moves, pulling the little hinged lever that usually has a wire "loop" at the end. The loop is hooked around the shutter trip lever and gives it a tug. One problem that nobody else has mentioned. If you did not cock the shutter -- you could still fire the flash bulb and activate the solinoid. So, you could get a click sound and a flash -- but NOT fire the camera and not expose any film! OOOpppss!

[Dennis Mollura]

How does the bi-post connector trip the solenoid? Is there a physical connection or via a magnetic field generated by the connector?

[W K Longcor]

How does the bi-post connector trip the solenoid? Is there a physical connection or via a magnetic field generated by the connector?

We are not talking the bi-post on the shutter -- it is a bi-post which is part of the solinoid. Wires go from battery tube of flash gun to solinoid. Batteries in flash power the solinoid and cause it to move. That movement trips the shutter release.

[aduncanson]

We are not talking the bi-post on the shutter -- it is a bi-post which is part of the solinoid. Wires go from battery tube of flash gun to solinoid. Batteries in flash power the solinoid and cause it to move. That movement trips the shutter release.


Evidently the two pins of the bi-post push through the holes near the bottom of the solenoid. See the picture in the attached ad. (Sorry about that, I have no association with the seller. I hoped to find a decent photo of a solenoid on graflx.org.)

http://cgi.ebay.com/GRAFLEX-FLASH-SOLENOID-2-FIT-VIEW-CAMERA-LENSES_W0QQitemZ310076688453QQihZ021QQcategoryZ64354QQrdZ1QQssPageNameZWD1VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

[Dennis Mollura]

Got it. Thanks to both of you.

[John Cahill]

Just wondering what the solenoid on the Speed/Crown Graphic shutter assembly does? All that schooling and I still don't know what a solenoid is for...

******
I think it was a fellow named Mendelsohn in the mid-late 1930s who applied the solenoid principle (a coiled electromagnet with a sprung rod inside) to the problem of firing the shutter and bulb at the same time--the Mendelsohn Syncronizer. As others have stated, it because a standard when plugged into the Graflex, Kalart, or other flash gun. Proper synching was done by adjusting the length of the connection to the shutter release using that knurled nut for the shorter peak M type bulbs.
As a kid photographer on the college newspaper, I usually got to use the 4x instead of the 2 1/4. Told "always test your solenoid before pulling the dark slide for the shot." I did so once, staring intently at the lens; and yup, I had a bulb in the gun. Saw flying saucers for many minutes, I did, I did.

[Dennis Mollura]

Great story - and thanks for explaining the adjustment nut on the solenoid.