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Testing Graphic Supermatic X Sync

 
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gdi



Joined: 27 Jun 2010
Posts: 26
Location: ct

PostPosted: Thu May 05, 2011 2:17 am    Post subject: Testing Graphic Supermatic X Sync Reply with quote

Anyone know how I can test the bi-post x sync on the Graphic 127mm Supermatic? I tried putting an ohmmeter on it an firing the shutter, but I get nothing (1.00). Will the circuit only close at a certain shutter speed or something?


Thanks
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Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Thu May 05, 2011 3:29 am    Post subject: Reply with quote

I usually use a light bulb and battery to test the contacts. And I prefer to over volt the lamp (4.5 or 6v on a 3 v lamp) so that I can actually see it get bright. (3 volts on a 3v lamp doesn't have enough umph to heat the filament in the fraction of a second the contacts are closed)

There isn't a whole lot going on inside a supermatic X, there's a whole empty section where the gear train for all the timing delay circuits were. Kodak just connected a couple pieces of brass to two points that close when the shutter is wide open.
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45PSS



Joined: 28 Sep 2001
Posts: 3219
Location: Mid Peninsula, Ca.

PostPosted: Thu May 05, 2011 3:53 am    Post subject: Reply with quote

If you are using a Digital VOM on the low ohms or auto ranging setting then on the 1 second shutter speed you might see the display go to something other than infinity for a fraction of a second, faster shutter speeds will not show anything as the contacts are only connected for a milli second or less. If you are using an analog VOM set it to the highest ohm scale and you will only see the meter pointer deflect about the width of the pointer except for the 1 second shutter speed then it may deflect 3 or 4 meter pointer widths.

Standard flash sync contacts are .001 to .003 apart when open. The shutter cam closes the contacts when the blades are between 99% full open and 1% closed from full open. At 1 second shutter speed the shutter blades take 1/2 second to go from fully closed to fully open and 1/2 second to go from fully open to fully closed if the speed is correct.

Les's suggestion to use a lamp and batteries is a good way to test, the other is to open the shutter and verify that the contacts are good and make contact visually.
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C. Henry



Joined: 13 Dec 2005
Posts: 357
Location: North East Georgia, USA

PostPosted: Thu May 05, 2011 1:53 pm    Post subject: Reply with quote

An even simpler test is to connect an electronic flash (strobe) unit, preferably one with a 6 or 12 volt trigger circuit, to the shutter and see if it fires when the shutter is tripped.

C. Henry
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gdi



Joined: 27 Jun 2010
Posts: 26
Location: ct

PostPosted: Thu May 05, 2011 10:32 pm    Post subject: Thanks for all the tips Reply with quote

I couldn't get anything to work, so I took the front cover off the shutter, then the internal plate, wiped the contacts off a bit, and slightly bent them toward the contact surfaces. I then got a good reading on the Ohmmeter, so I assembled it and it worked nicely!

Now I have to rig a decent sync cord - I'll have to cut off the zip cord close to the bi-post connector and splice in new one. The plastic sheathing is brittle and actually falling off. I plan on using a smallish flash (Vivitar 2500) and mounting it to a light bulb base to utilize the Graflite and Reflector.

I have to research how to expose with the flash - I'll be using Fuji Instant film - 3200ISO B&W - so I am concerned with coverage and hot spots or overexposure. SO I welcome any tips on that as well!


Thanks!
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45PSS



Joined: 28 Sep 2001
Posts: 3219
Location: Mid Peninsula, Ca.

PostPosted: Fri May 06, 2011 2:53 am    Post subject: Reply with quote

http://www.cameramanuals.org/flashes_meters/vivitar_2500.pdf
if you need the manual.

It has been reported here many times that an electric razor power cord will fit the Bi Post connector on the shutter.

Google is your friend. Search for Film Speed and find several film speed charts.

ISO 3200 is two stops faster than ISO 800, 3 stops faster than ISO 400.

What format and lens are you using?
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gdi



Joined: 27 Jun 2010
Posts: 26
Location: ct

PostPosted: Fri May 06, 2011 9:43 am    Post subject: Reply with quote

45PSS wrote:
http://www.cameramanuals.org/flashes_meters/vivitar_2500.pdf
if you need the manual.

It has been reported here many times that an electric razor power cord will fit the Bi Post connector on the shutter.

Google is your friend. Search for Film Speed and find several film speed charts.

ISO 3200 is two stops faster than ISO 800, 3 stops faster than ISO 400.

What format and lens are you using?


Thanks - I am familiar with flash - but on smaller formats. I was concerned that using a smallish flash designed for 35mm would provide a severe drop-off at the edges with 4x5 & 127mm Ektar. I gave it a shot last night and found it did work fine in the 8-18 foot (or so range).

So I have it fairly well dialed in for those mid ranges and the fast Fuji film. I'd like to eventually find a bare bulb electronic flash, but for now the little Vivitar will probably be OK at 3200.
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Henry



Joined: 09 May 2001
Posts: 1442
Location: Allentown, Pennsylvania

PostPosted: Fri May 06, 2011 4:22 pm    Post subject: Reply with quote

As you know, Vivitar has a proprietary flash connector design that is not interchangeable with anything else that I know of. I had Paramount Cords make me a bipost-to-Vivitar synch cord for use with my Vivitar 2800 flash on the Century. See http://www.paramountcords.com/graflex.asp. The Vivitar tip is their #9, bipost their #13. Look on the products drop-down list on their Home page to see the particulars.

I might add that the custom cord works great, a one-time investment for an essential piece of quality gear---not bad!
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45PSS



Joined: 28 Sep 2001
Posts: 3219
Location: Mid Peninsula, Ca.

PostPosted: Fri May 06, 2011 8:54 pm    Post subject: Reply with quote

Check ebay for Metz flashes. The 45CL/CT and 60CT series are going for decent prices these days.

The 127 Ektar, http://www.cameraeccentric.com/html/info/kodak_4.html ,
has an angle of view of 36 degrees X 46 degrees focused at infinity on 3 1/4 x 4 1/4 format (standard lens for this format) so your Vivitar will work best at the wider angle settings. There is no direct relationship between the 35mm lens and larger format lens but a little research should give you the angle of coverage for them and the formulas to convert to larger formats if needed. Slower film will show the flash weakness quicker than fast films.

The beauty of photography is that photons of energy are photons of energy whether generated by a huge sphere of fusion reaction, an incandescent light bulb, a fluorescent light bulb, a flash bulb, or a xenon tube.

We only have to be concerned about the intensity, area of illumination, and color quality when working with color medium.
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gdi



Joined: 27 Jun 2010
Posts: 26
Location: ct

PostPosted: Tue May 10, 2011 11:38 pm    Post subject: Reply with quote

Well I really lucked out - I found a guy selling a bare bulb Sunpak flash for a reasonable (relatively) price. As I was coming home from picking it up, I dropped by the local camera shop and looked on the $1 table and found several Paramount cords.

I bought one that was a coiled bi-post to household and one that was a short PC male to female. I was able to attach a female household plug to the PC cord and now I can connect everything. The Sunpak 120j is quite powerful and has flexible controls, so I can adjust for the 3200 film easily by stopping down and cutting the flash output to 1/8.

I took a number of shots on the instant film today at an inside event and the flash shots were great. (At least the ones that weren't serious operator error!)

Now I have to hunt down or make a cord for my Super Speed - there wasn't one on the discount table unfortunately! I heard you can use PC Molex connectors, so, I may give that a shot.

Thanks again.
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