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03-29-2017, 02:16 PM   #1
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Flash sync problem with cla'd MX

Seems that the hot shoe and x-sync port don't always fire and when set at 1/60 my exposures are consistently way too thin (as if the flash/strobes) never went off. I am making sure I am plugging into the x port and not the M and making sure I have it on 1/60, and also factoring in the contrast filters when used and double checked the metered reading off the sekeonic flash meter and that it correctly had the right iso.

Ambient exposures are fine just not flash when aiming only for strobes, this unit was Cla'd by Eric last November by the previous owner.

Tested both a manual flash mounted directly to the hot shoe as well as some alien bees plugged into the PC sync socket. They do trigger but if I had to take an educated guess what is happening the timing seems off.

03-29-2017, 02:33 PM   #2
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Email him directly and discuss the matter.
03-29-2017, 02:34 PM   #3
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Hi KB,
Open the back, and eyeball the flash sync at 1/60th.
03-29-2017, 02:44 PM   #4
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Also noticed in the studio when I try to meter for ambient against neutral gray and go down to 1/8 on the shutter the meter would zap to red over exposure and no matter if I spin the aperture down to f/22 it stays at red over but if I go to 1/15 I can stop down to f/8 for green led

But then I go to 1/125 it's stuck at red over. My gossen digisix meters EV 10 for the scene reflectively (which is 1/15 f8, 1/30 f5.6 and so on)

By the way the PC sync should work with the timer right? Sync Wouldn't fire off the timer. (doing a test roll with writes ups in frame)

03-29-2017, 05:01 PM   #5
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QuoteOriginally posted by kb244 Quote
Also noticed in the studio when I try to meter for ambient against neutral gray and go down to 1/8 on the shutter the meter would zap to red over exposure and no matter if I spin the aperture down to f/22 it stays at red over but if I go to 1/15 I can stop down to f/8 for green led
OK, Please refer to manual page 22.
That might indicate that you either have set ASA dial to iso 1600, or the camera has a fault that it "thinks" it is set to iso 1600.
So I suggest to press down the little silver button and run the ASA dial through its ranges a few times, as that might reduce any contact resistance from dis-use.
It is a bit difficult to adjust that ASA setting, use two hands.

I just tried the MX here, and at ASA 1600, it follows what you wrote, which is normal, and as described on page 22 although page 22 does not explicitly say that
the Red led is the default when you go into the white areas on page 22.
Good Luck!
03-29-2017, 08:32 PM   #6
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I left it at school so I'll have to try cycling the iso setting when I get back there tomorrow.
03-30-2017, 11:16 AM   #7
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K, so definitely something up with the meter, turning it around to all ISO didn't do anything as I would have it turned on 200, and it would show that behavior, then go to 100 then seems normal, but then 64 gets the behavior again, or 1600 normal. But I noticed that when I'n on one with the stuck red-over, if I tap the top of the shutter dial it'll work normally from there.

In regards to the flash sync, I'm chalking it up to a bad RF transmitter as we have two in the studio (both neewer brand), and I used the second one on the test roll, seems like one of them is so delayed that even though it fires it's like it's either firing well after the shutter or too soon (though more likely well after, because too soon wouldn't make sense, since it's instant for x-sync no?)

With the second one, you can see an exposure difference between using the shoe, and using the cord directly (exposure difference between 1/60, 1/30, 1/15 simply reveals more ambient light, though the two I tried without the room light off for whatever reason simply did not fire). Also I suspect that the AB's sync cords has too a tiny pin that needs to be pushed towards the side with a tack so that it makes contact with the inside of the sync hole.

Though still not sure what's up with the pc sync not firing when the self-timer is used, or the meter going wonky. I'll have to contact Eric with my findings and see what can be done since I bought the camera from the previous owner mostly because it was advertised as fully CLA'd showing a scanned receipt from him.



03-31-2017, 11:34 AM   #8
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Seems I'll have to send it to Eric to address the meter, unfortunately he doesn't transfer warranty so whatever guarantee the previous owner advertised with the camera being CLA'd and all won't apply to me.

Basically with the meter it keeps getting stuck in the red overexposure LED, I noticed that if I wiggle the shutter speed knob like I'm getting ready to turn it, especially if I tilt it ever so slightly forward all of the LEDs will light up in cycle up and down. Sometimes it'll behave normally but not always. Just kind of sucks cuz I don't want to be without the camera with 4 weeks left for this class.

Edit:
Far as I can tell, based on my test negs, the flash sync seems to work fine so as long as the pin is securely pushing up on the inside of the sync terminal (some of the cheaper sync cords don't have as thick a pin in the middle). And while it would be more of a pain in the butt for me I can still meter with my Gossen Digisix to get thru the semester.

I wonder if there is any possibility at all that the cheap neewer radio trigger (which can be plugged into the pc sync socket or mounted on the hot shoe) could have in any way shorted the meter circuity. In my mind I don't think it could considering that some of the flash units back in the day would have trigger voltages upward towards 250V and the new digital stuff is rarely over 3V to 6V, but then I don't know what the internal circuity of the camera is like and I didn't notice the problem until I was in the studio at the beginning of this thread.

edit #2: meter appears to work 95% of the time whenever I push and hold down the pin on the shutter dial (the one you have to push down to change the ASA), if I let go of it, it jumps back up to red over exposure. More specifically if I press down on the shutter speed dial closet to the rear corner of the prism/viewfinder.

Last edited by kb244; 03-31-2017 at 12:31 PM.
03-31-2017, 12:58 PM   #9
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Since I'm not doing anything in the digital lab right now (most any student here already has stuff to do in the studio, or working on a print), I grabbed my spanner, air bulb, some shims etc etc just in case.

First thing I did was unscrew the bottom plate since that's easy and take a look at the shutter/meter contact just to be sure even though if that was shorted/etc it simply wouldn't light up, but just to be sure I did so anyways and sanded the contact points just in case any kind of tarnish or what not wasn't allowing connectivity. Course tested and still had the problem so I know it wasn't that point.


Then I unscrewed the center screw on top of the shutter dial after setting it to 1/1000th and ISO 100, and lifted the dial off. Since I figured the problem must be there if it rights itself when I press down on the rear corner of the shutter dial.

From there I looked around to see if anything loose or lodged could be in there, blew around it with the air bulb as well as the underside of the dial. Checked the meter reading with the shutter dial removed which seemed to be fine for 1/1000th @ ISO 100 pointing out the window on an overcast day to see if the reading goes down.

Then I put the shutter dial back on, screwed it down, then while trying a couple ISO on both ends and middle, I looked thru the viewfinder, got a green reading, pointed until it went red under, turned the shutter dial 1 stop to get a green, another red, then turn dial to get green again (basically every time I hit red, move the shutter dial 1 stop and should be green again) also cycled the aperture a few times just to be sure.

It seems like it worked itself out because I cannot re-produce the 'stuck' red over, maybe some kind of non-conductive dust or shaving or something other got stuck in there and wasn't allowing contact, I didn't see anything get blown out when I lightly hit it with the air bulb when the shutter speed dial was removed.

I also compared readings to my Gossen Digisix (via incident) to see that it received the same reading off something that was about as close to middle grey as I could find.

Just looking at the bottom plate removed can tell ya the inside is ***clean*** :P not sure why that makes me giddy, but it does.
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