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Kodak Ektar with Flash Supermatic Shutter
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sat Jul 06, 2002 8:30 pm    Post subject: Reply with quote

I just purchased a 1947 (SN# begins with ES) Kodak 101mm Ektar with Flash Supermatic Shutter for my Century Graphic. The shutter has delay settings for F & M flashbulbs, a lever that you cock after cocking the shutter...a geared timer, of sorts, that, I assume, introduces the required delays for the two types of flashbulbs. My question is this: should this shutter fire an electronic flash with no delay if the flash delay isn't cocked? I get slight continuity with an ohm-meter clipped to the bi-post when I fire the shutter...but it won't fire a flash without the delay mechanism cocked. There is no "X" setting. I would appreciate any information on this. Thanks, Fred.
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extraparts



Joined: 10 Feb 2002
Posts: 59
Location: texas

PostPosted: Sat Jul 06, 2002 9:47 pm    Post subject: Reply with quote

I don't know of anyway you can successfully fire an electronic flash with that shutter.

That is one of the reasons that some collectable cameras (I'm thinking Zeiss Ikonta) have a several hundred dollar price difference between cameras with shutters that acomidate electronic flash and those that don't.

The problem is that flash bulbs take a while to get up to full brightness, and then stay that way for a while.

Electronic flashes fire almost instantly and their duration is very short.

Therefore with bulbs, you must trigger the bulb and then wait to open the shutter. With electronic flash, you must wait for the shutter to open and then fire the flash. The delays are reversed. Even if you could fire the electronic flash at exactly the same time you triggered the shutter, it would fire and be out before the shutter had time to fully open.

Sinse the problem is to delay the electronic flash from fireing you would think someone could build an adapter to go between the shutter and the flash but I have never heard of one.

Sorry.

However, press 40s are about $1.00 each on ebay and where can you get an electronic flash with a 400 guide number as cheap as that?

Besides if you buy the "focal plane" flash bulbs you can use them with focal plane shutter speeds that won't work at all with an electronic flash.


Neal
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jdman



Joined: 13 May 2001
Posts: 302
Location: Midwest

PostPosted: Sun Jul 07, 2002 12:05 am    Post subject: Reply with quote

The flash supermatics should fire the strobe, because they have 2 sets of sync contacts. One I understand works all the time but has a 10,000 ohm resistor in it to prevent firing flash bulbs. The 2nd contact is used with the flash timer for the 5ms and 20 ms delay for flash blubs. I have 2 Flash supermatics and one works like yours, but the other one fires the strobe without the timer and is in sync. I suspect that the x contact is either dirty or not making contact. For more information on Flash Supermatics search Goggle, and the articles explain this. Russ
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sun Jul 07, 2002 3:29 am    Post subject: Reply with quote

Thanks, Russ. I had hoped for this answer. The shutter contacts are trying to work without the "M" and "F" lever cocked...and it does appear that there is too much resistance..apparently from dirty contacts as you suggest...to trigger the electronic flash...a Heiland Strobonar II I have repaired. The Heiland works well on my Speed Graphic with a Wollensak Rapax and "X" sync, so I know the flash is ok. I'll see if I can clean the contacts with a little Ronsonol lighter fluid. Thanks to the other reply too, but I have a ton of flashbulbs including some 22's...11's...5's...25's...you name it. I use them too, but I want the stop action capability of the 1/2000th of a second Heiland Strobonar. Not sure of its flash guide number at this point after my repair, but it dumps 950 volts through the xenon tube...and is BRIGHT. Thanks again to everyone. Fred.
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sun Jul 07, 2002 3:58 am    Post subject: Reply with quote

P.S. I guess it's possible that the 10,000-ohm resistor in the second set of contacts that prevents firing flashbulbs may be introducing too much resistance to fire the Strobonar too. I'll try it with a Vivitar tomorrow. Thanks again. Fred.
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extraparts



Joined: 10 Feb 2002
Posts: 59
Location: texas

PostPosted: Sun Jul 07, 2002 4:44 am    Post subject: Reply with quote

You guys seem to be right and I was wrong. I hooked my supermatic to my strobnar and put the lens over the flash so that if the shutter wasn't open, I wouldn't see any flash. It seems to light my cealing up just fine if I don't cock the delay, and I see nothing if I cock the delay.

I am glad to know this so now I can use mine with electronic flash.

Sorry about the wrong post, thanks for setting me stright.

Neal
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jdman



Joined: 13 May 2001
Posts: 302
Location: Midwest

PostPosted: Sun Jul 07, 2002 4:56 am    Post subject: Reply with quote

The article mentions shorting out the resistor to get some strobes to fire, the problem is if you do that then the bulbs will fire without delay. Russ
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sun Jul 07, 2002 11:35 am    Post subject: Reply with quote

If a person would keep a flashbulb out of the flashgun until he was ready to take a flash shot by cocking the shutter delay, how could by-passing the resistor be a problem? The flashbulb is fired before the shutter opens with the delay mechanism cocked...and THEN after the shutter opens the second set of contacts closes for the strobe. The flash bulb has already fired, so what does it matter? Thanks for the Google tip, Russ. I think I now fully understand the internal working of the shutter. However, I didn't know it was an accepted "fix" to shunt the resistor, but that was what I was thinking about attempting. Apparently the resistor is limiting the trigger voltage for the Strobonar too much. My original Century shutter will sync to flashbulbs at the slow "red" speeds but is off on the "black" speed settings for strobe...hence my desire to use the Ektar and flash Supermatic for flashbulbs AND strobe...plus the added advantage of the Ektar, which is probably superior to the Graflex Trioptar. Thanks again. Fred.
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sun Jul 07, 2002 2:14 pm    Post subject: Reply with quote

At the risk of belaboring the subject, but to verify some of the info contained in these posts...this morning I attached a precision ohm-meter to the bi-post flash connection on the Flash Supermatic shutter. I arbitrarily set the shutter at 1/25 and cocked it, without the timer for M & F lamps employed. By holding back the cocking lever as I tripped the shutter...and then SLOWLY allowing it to go through its sequence...the shutter opened...the X contacts closed and gave a precise reading of 10K ohms. No dirty contacts...just the resistor. I then re-cocked the shutter and set the timer for M lamps. I tripped the shutter...held the timer lever back and allowed it to slowly trip. There was an instantaneous contact closing of 0 ohms...followed by the closing of the X contacts with a resistance of 10K ohms. SO...I am going to attempt to solder a small wire around the 10K resistor so the Strobonar will fire...as per Russ's post. Thank you all. Fred.
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Sun Jul 07, 2002 3:39 pm    Post subject: Reply with quote

I know I'm getting verbose on this subject...but must report further tests I conducted on my 1947 Kodak Ektar Lens/Flash Supermatic shutter. My tests are doubting much of the above info. I am doubting the existence of the second set of contacts. The 10K resistor is connected from the top post of the bi-post to the frame, or chassis ground. I get 10K-resistive contact closure even while cocking the shutter. Also, after tripping the shutter I can cause this 10K (10,000 ohms)-resistive contact closure when pressing the shutter release without the shutter cocked. So, without the resistor in the circuit, flashes would be firing when the shutter is cocked., or whenever one should happen to touch the shutter release What's apparently happening is this: The resistor is there to prevent the flash from firing...and the M-F shutter delay mechanism by-passes the resistor at the correctly timed moment for flashbulb sync. This shutter will not sync to a strobe, unfortunately. Fred.
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extraparts



Joined: 10 Feb 2002
Posts: 59
Location: texas

PostPosted: Sun Jul 07, 2002 4:42 pm    Post subject: Reply with quote

I may actually try this if I get some time on my hands:

If I put my flash meter in the camera, and point the flash at the lens and the X sinc is working, won't I get the same reading with the X sinc as I would get if I just left the lens open and poped the flash? If I get a lesser reading with the X sinc wouldn't that mean that the shutter blades were not all the way open when the flash fired?

Aside, I also have a Trioptar, and it is my understanding that it is the entry level lens. (Having said that it is also much newer than my Ektars, but I too would assume the Ektars were better.)

However, with the Ektar, you may have a huge image circle and if you don't mask it down with an adjustable shade, you may get flare from all the extra light going into the camera. (great debate right now on Large Format Forum and as usual great minds don't think alike. At least not in Large Format Photography)

Also aside my "Flash Supermatic" has Bayonet not by post contacts, and I don't know if that means it is older or newer than yours. It is not the "Supermatic X" shown pictured on one Graflex.org pages which doesn't have the F/M adjustment at all.

Neal
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jdman



Joined: 13 May 2001
Posts: 302
Location: Midwest

PostPosted: Sun Jul 07, 2002 5:31 pm    Post subject: Reply with quote

I got may information on the full sync capability from the main Graflex.org site. But since I also have one that does not fire a strobe, I guess i will take a look inside. In another place, i remember it said to take a single strand of wire (Small)and ground the bi-post nearest the cocking lever. Will report back if anything positive comes of this. Russ
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extraparts



Joined: 10 Feb 2002
Posts: 59
Location: texas

PostPosted: Sun Jul 07, 2002 5:33 pm    Post subject: Reply with quote

Are we sure that resistor is to adapt a bulb circuit to electronic flash?

Sometimes in automotive circuits we will put a resistor accross contacts to protect the contacts from excessive voltages that can eventually burn the contacts. (Some automotive relays come with the resistor built in.)

Does anyone know if it is accross the contacts or in series?

Neal
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clnfrd



Joined: 26 Mar 2002
Posts: 616
Location: Western Kentucky Lakes Area

PostPosted: Mon Jul 08, 2002 1:44 am    Post subject: Reply with quote

Gentlemen...to continue this study in self- contradiction...it appears there must be two set of contacts as Russ suggested, but I doubted. All this without actually tearing into the shutter. What I get with my ohm-meter is this: there is a 10K resistor connected from the post nearest the cocking lever connected to ground, or, the frame as it were. When the shutter is tripped without using the shutter delay, the other post is switched to ground with a set of contacts thus giving a reading of 10K across the posts because, in effect, the 10K resistor is in series with the contacts, the shutter metal frame being part of the circuit. When the shutter delay mechanism is cocked and the shutter is tripped, another set of contacts by-passes the 10K resistor, resulting in O resistance across the posts and the switching effect will fire a flashbulb by providing the battery voltage to the lamp. If the resistor were by-passed from the top post to ground with a wire, the electronic flash or the flashbulb would fire during the cocking of the shutter. Actually, the circuit would work with the resistor totally removed rather than by-passed. The resistor must be for surge suppression, because it is momentarily in the circuit as the shutter release is pressed just before the contacts close that fire the flash when using the shutter delay timer. Fred.
P.S. I've removed the front plate on several other shutters for cleaning...but how does one remove the front plate for access to this one? If I remove the front lens element and the one screw I see...what next?
[ This Message was edited by: clnfrd on 2002-07-08 04:25 ]

[ This Message was edited by: clnfrd on 2002-07-08 04:34 ]

[ This Message was edited by: clnfrd on 2002-07-08 04:49 ]
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extraparts



Joined: 10 Feb 2002
Posts: 59
Location: texas

PostPosted: Mon Jul 08, 2002 2:13 pm    Post subject: Reply with quote

I am at work and not near my shutters. I will check tonight. However, from memory, I think you will see a screw near the center with a flat side on the head. (I think it has two spanner holes instead of a slot.) Turn this screw so that the flat side is against the hole where the lens element goes, and you will then be able to rotate the face until some half moon tabs on the face line up with the slots on the center of the shutter. It can then be lifted off.

I looked in my 1947 edition of “Graphic Graflex Photography” and it shows both the “Flash Supermatic” and the “Supermatic X” shutters. It says that the 10,000 ohm resistor is used to keep the bulbs from firing when the shutter is fired without the delay mechanism cocked. It says that the Supermatic X does not have that resistor. It also says that to use flash bulbs with the Supermatic X shutter you must install a solenoid to trip the shutter.


Neal
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