Spotmatic light meter problem

Discussion in 'Pentax' started by ridinhome, Apr 5, 2010.

  1. Hello all,
    Just got a Spotmatic off of ebay. Took it to Phototech in New York for a CLA - they said the meter was working, and had been calibrated. Installed a Wein Cell in it, but when I turn on the meter, it pegs to the + end of the scale and just stays there. Nothing I can do will budge it. I change the shutter speed, the f-stop, even the ISO, but nothing moves it. Any thoughts? The lens I have on it now is a Coligon 80-205 f4.5 if that makes any difference.
  2. Not an expert on these cameras but things I would try (if you haven't already):
    • turn on the light meter with the thumb switch on the left-hand side (side with rewind knob) of the camera.
    • some cameras expect that the film advance lever is partially extended away from the body to activate the meter (not sure about spotties)
    • battery check by setting ISO/ASA to 100 and shutter speed to 'B', then press the meter switch (needle should drop)
    • check that battery is facing the right way. The manual I saw indicated that positive should face the top of the camera.
    I wouldn't expect the lens to matter.
  3. Thanks Andrew, that's helpful. I did the battery check - ISO 100 / shutter speed to B adn the needle did drop, so I guess that means the meter is working. Also, after playing around with it a little, it does seem to respond somewhat, though its a little sensitive (one or two turns of the shutter speed dial and it pegs). Perhaps I'm just not used to match needle metering. Guess I'll just have to run a roll through and see what happens. It would suck if the meter doesn't work, but I guess I can always use sunny 16.
    • some cameras expect that the film advance lever is partially extended away from the body to activate the meter (not sure about spotties
    Really? ME Super wouldn't be one of them, would it Andrew? My light meter/LEDs sometimes go all funky on me but then when I press it again, it lights up fine... never noticed where my rewind crank is...
  4. Kayam, you could always get a handheld meter. How did you like Phototech for your CLA?
    Somanna, it wouldn't be the rewind crank, it would be the 'rapid wind' film advance lever--most of these are designed with a stand-off angle of ~20 degrees away from the body. For example, with my MX, the meter lights will flicker on half-press and go dark when I stop half-press, unless the film advance lever is pulled out to its 20-degree standoff position. If in standoff position, the meter remains active for ~30 seconds. I believe KX meter doesn't work without the lever out either.
    This isn't so unusual, Konica Autoreflex T3 and T4 work this way too--in fact, T4 has a little button below the film advance lever to push to retract the lever and turn off the meter!
    As for the ME Super, I don't remember offhand if it works this way, and I didn't see it explicitly mentioned in the manual, so it may not. If you see funky flickering that might indicate weak batteries--the manuals says:
    "WEAK BATTERIES: When batteries are low, the "2000"-"4S" LED shutter speed dots will commencce to flicker on and off. This indicates that batteries should be replaced. (NOTE: the LEDs outside the "2000"-"4S" battery check range [i.e., "OVER"-"UNDER"-"EF" and "M"] normally flicker in certain modes and should be disregarded as low battery indication.)".​
    Ah, the good old days when companies were desperate to keep their electronics as simple as they could get away with.
    Thinking about this, I wonder how this works with a winder installed? I don't have a MX winder though, only ME.
  5. Andrew - yeah I could get a handheld. Any particular suggestions?
    I like Phototech a lot. They're not the cheapest place around, but they do a very professional job and the price includes a 6 month warranty. I've had three cameras CLA-ed there so far, including the Spottie, and they're very good about giving me a heads up about expenses. They even threw in a Wein MRB400 for free when I took the Spottie there, without having to ask about it.
  6. Andrew; yes I meant the advance crank, my bad! It's hard to remember actual names of parts of old cameras since nowadays it's "push the button..." :)
    I do have new batteries in it. When I first them in and noticed the flickering, I read that warning. I thought I had gotten grime on them and so took them out, cleaned them, and carefully put them back in. Then I thought it was that batch of batteries, so tried another.
    I'm real curious to try the advance lever crank now... though I suspect I need to suck it up and send it to Erickson for CLA...
  7. Perhaps I'm just not used to match needle metering.​
    The Spotmatic is not match needle. It needs the meter needle in the centre of its travel to show correct exposure. This also indicates that the meter circuit is a bridge type circuit which is not sensitive to voltage so you can use a 1.5 volt silver oxide or an alkaline cell in there instead of the Wein cell.
  8. Kayam, to expand on what Steve said:
    Match needle metering generally has two indicators--one for the user-set shutter speed, and one for the meter reading. Typically in this arrangement, if you change the aperture, the meter needle will move, if you change the shutter speed the other needle will move. When the needles are matched together, that's using the meter-recommended exposure.
    Lots of choices on handheld meters. A few considerations:
    • Format/size - do you want a small one that can be mounted on the accessory shoe, a handheld one hung on a lanyard, etc.?
    • Digital or analog
    • Just reflected metering, or incident as well (most can do both) Reflected is what in-camera meters do, for incident you put the meter in the same light as the subject and point it back at the camera/direction you're shooting from. This is similar to using a grey card--it gives you a reading that isn't sensitive to the color/tone of the subject, just to the amount of light hitting it.
    • Spot metering (some can do this with attachments, or some are dedicated to do only this)
    • Battery type - many older ones relied on mercury batteries and now require adapters and/or wein cells
    • Some are selenium and don't require batteries. Not sure about possible accuracy problems over the years but in general they aren't as sensitive (smaller EV range) so don't work so well for long exposures.
    • Flash metering - the meter is live when you pop your manual flash/flashes and it tells you what aperture you need.
    I recently bought a Gossen Luna Pro F with the intention of using it with my as-yet-unused meterless pre-Spotmatic Pentax S1a.; The Luna Pro F is kind of bulky but has an analog-needle display, offers flash/incident/reflective and takes an easy-to-replace 9V battery. I believe there's also an available attachment that allows for narrower field of view--not quite a 1-degree spot, but narrower than 'normal'. As it is a little bulky I may also look into a more compact unit, even with fewer features but I thought a full featured meter would be better for learning what I like using and what I can do without.
  9. Hey, Kayam, maybe try some quick checks if that other stuff doesn't work out for you:
    • check to see if the film speed dial is seated right. Like, when you change the film speed, the knob should click back down; the dial is spring loaded, and sometimes it may be in a slight "up" position.
    • if the light source is over three stops stronger, then the meter will peg out at maximum; try lying to the meter by setting it for 60x, f/8, 100ASA while indoors with a tungsten lamp; then cycle through the shutter speeds to see if you can wake up the needle.
    • Wein cell batteries sometimes have a paper slip over one of the contacts; I take it that this has been removed?
  10. Hi John,
    Yes, took out the paper cover.
    It seems like the meter is much more sensitive in daylight than tungsten light. That said, my testing has been anything but scientific since I've only had time to play with the camera after and before work.
    Thanks for all the advice everybody! This is my first classic Pentax (have a ZX-7) and first ever camera with needle metering (match or otherwise) so I'm still feeling it out. It's such a lovely camera though, and I love the Takumar lenses.
  11. The Spotty needle should behave a lot like the LED indicators in your ZX-7 when in manual mode, though without the benefit of digital display of shutter & aperture. I also don't know whether the Spotty needle shows a whole +/- 3 stops like the ZX-7. It may only register a smaller range. For example, the 5 LEDs in an MX viewfinder only show +/- 1EV.

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