Gossen Pilot Service

Discussion in 'Accessories' started by henry_finley|1, Nov 8, 2021.

  1. I'm considering a Gossen Pilot that looks pretty nice, but my question is whether you can open it up and calibrate it. Thank you.
     
  2. You can open it up but you won't be able to calibrate it, it's all set, except for "Zero" adjustment, there's a screw on the bottom to turn and adjust the needle for a distance that represents roughly one "f" stop if the needle is not coming back to Zero. Otherwise, it's the selenium cell that is calibrated to a certain voltage and if the voltage drops over time, you can adjust the ASA to compensate.
     
  3. I'd shop for something far newer. The "adjustment" screw on the Pilot's back simply allows you to "zero" the needle with the sensor blacked out--a feature common to most selenium cell meters. Problem with relics is that a "working" meter isn't necessarily an "accurate" meter. Film and processing costs being what they are, I can't see the point of opting for something this old.
     
  4. I'd leave it alone.
    IME the way that selenium cells deteriorate is non-linear. Meaning that a simple ISO rating adjustment doesn't compensate for a sensitivity loss across the whole scale or across ranges.

    In fact a good test of a selenium meter's condition is to find an illumination level that sends the needle just to full-scale on the low-light range, then switch to the higher range and see if you get the same reading. If not, then the cell is dying and there's almost nothing that can be done about it. The meter movements are so delicate that attempting to adjust their sensitivity is highly likely to result in more damage, and a small amount of dust, or worse, ferrous metal swarf between magnet and coil can jam the meter solid.

    That's not to dismiss old selenium meters altogether - I have at least 4 accurate and smoothly working Weston Master IIIs and 2 Sekonic L398s - but they're always a risk and I have several other totally dead, useless and unrepairable Weston Masters to prove it. Plus they're never going to compete with a CdS or photodiode meter in low-light sensitivity.

    In short, get something more modern that takes an easily obtainable battery. A Minolta Autometer for example.
     
  5. Here we have a view of the internals of a Gossen Sixtino nee Pilot in the US. This meter has accuracy problems and it doesn't matter what I do with it now so I've taken it apart to show what it looks like inside. Not much going on in there, just a motor and needle, a magnet, wiring, a selenium cell and a broken diffuser (also stuck, the reason it broke). The only repair that would bring back the accuracy, to "calibrate" it, is to replace the selenium cell with a new old stock one but I doubt there is any around anymore. I'm not even going to try.

    I was suspicious of this used meter from the start, the needle was very lively, but unfortunately, not accurate. I tested it against my brand new Sekonic L208. Perhaps not the best meter to use as a test meter, but it's the only new meter I have at the moment.


    (A) Internals - Pilot.jpg


    Brand new Sekonic L208 (below), I used to compare readings of my many other meters in a range of lighting conditions. Out of all the light meters I have, both built-in camera meters and hand-held meters, only two matched precisely with this new Sekonic, my Petri FT SLR, and one of my Polaroid EV meters. There were two others that came close,, but rather than being precise, they were just "very close". One was the meter in my Mamiya Metra which I repaired, and the other was my Kodak Retina 111c which I was assured when I bought it, the meter was "accurate" (The camera wasn't used, but displayed, with it's selenium cell covered under the meter's door)

    (B) Brand New L208.jpg


    Polaroid EV Meter (below), another Gossen I'm sure, it has many similarities to other Gossen meters of the same shape and size, but the needle is at the other end of the meter. I have three of these Polaroid EV meters in working condition but this one is the only accurate one when compared to the Sekonic L208, every EV number I tested was spot on. Problem is, I have no use for it, but at least I know it's a good one.


    (C) EV Polaroid Meter.jpg
     
    Last edited: Nov 18, 2021
    m42dave likes this.
  6. Even more sparse than the innards of a Weston Master, but probably a lot easier to get into!

    I can see the aesthetic attraction of old meters, but they're not really a practical proposition. My collection of old Sekonic, Gossen and Weston meters has dwindled, through wearing out, down to one working Lunasix 3, a Studio L398 and - obstinately - 3 or 4 Weston IIIs. The Weston III meters just keep plodding on and on.


    00dj3S-560597384.jpg

    00dj3S-560597384.jpg
     
    Last edited: Nov 19, 2021
  7. I've got one of these little German made Polaroid meters which is also "spot on". The thing with Selenium meters is that many don't work at all, many give inaccurate readings, and a few are still accurate and usable. I've got two others in the third category, a little Gossen Pilot, and a later Vivitar branded meter, which I don't hesitate to use. All the others in the first two catgories are round filed.
     
  8. I get that those match needle meters compliments a classic film camera, but a direct readout meter such as the Sekonic L-308 series is just so much faster to use - they have been in production for many decades and the earlier versions shouldn't be too expensive second hand (plus they work as flashmeter as a bonus).
     
  9. I have lost my good Pilot somewhere, but should note that it seems there were two versions of the Pilot. The first requires disassembly to calibrate, but there was a later one that had a tiny little screwhole in it that allowed it to be recalibrated without disassembly. I am not talking about the zero-adjust, which is always there, but a little hole in the case.

    If you have a Pilot, look carefully around the case for that little hole. I can't now remember exactly where it is, but I know that my later one had it, and it was indeed possible to fine-tune it. Unfortunately, the last time I saw it was in a car that no longer exists.

    I have a couple of those old Polaroid meters, and surprisingly they're still accurate. I think some, at least, were made by Gossen, and they seem to have been made well. I've had less good fortune with Weston Masters, though when they work they're very nice.
     
  10. That "tiny screwhole" might be for the hold-down screw in the bottom of it's case, the plastic case the meter is protected in. Anyone who bought a Pilot/Sixtino without the case might wonder what that tiny screw hole in the bottom of the meter is for, it's simply for the coin operated screw in the protective case to keep the meter secured in there. It's a blind screw hole so no dust or dirt can enter the meter.

    I'm not suggesting some meters don't have an adjustment besides the Zero adjustment. The extra adjustment would be for needle spring tension, I doubt it's for anything else. Some rangefinder cameras in the 50's had screwed plugs in their top covers, and after removing the plug, a screwdriver is inserted to adjust the spring tension for the inbuilt meter. I've never seen instructions on how to arrive at the correct meter readings by using this spring tension method. Without instructions, it would be just trial and error. My Mamiya Metra has that method of calibrating it's meter but I don't touch it because the meter is not bad the way it is. If it ain't broke, leave it alone.

    The Sekonic L208 has absolutely no adjustments at all. I had to figure out for myself how to check the needle's Zero. From what I observed, after blocking all light getting to the cell, was that when the green pointer is turned to the extreme left side of the dial, the red needle exactly matches the green pointer when the side button is pressed. Well, almost exactly, but if the needle ever changes from that position, I'll know there's something wrong with the meter.
     
  11. The most internal adjustment I've yet seen on a meter was in a Gossen Lunasix 3. There are separate potentiometers for battery-check, high and low range FSD, and linearity - all with no indication of which pot does what. And to make matters worse there's a good deal of 'crosstalk' between the linearity and FSD pots!

    I eventually managed to figure out how to recalibrate it to use an alkaline cell rather than a mercury one, but it required almost micro adjustment of two of the pots.

    Gimme a photodiode-based digital meter designed to take a common battery any day. ;)
     
  12. I also have a small accumulation of Gossen Pilot meters, and none seem to lie beyond their life expectancy. As for my Sekonic Twinmate, it doesn’t agree with any of my Gossen Digisix, LunaPro F, or Pentax or Gossen spot meters. Moreover, there doesn’t seem to be a way to adjust Twinmate.
    On the other hand, long ago, when I first replaced the little exposure guide that came with every roll of film with a light meter, the advice was to take notes and calibrate meter with camera, since both meter and camera were unique. Before entrance of digital capture, good cameras, new or used, were very expensive and few photographers had more than one or two cameras so calculating camera with meter was easier.
    I wish my Twinmate were more in agreement with my other meters because I prefer its simpler match needle to Digisix EV readout, and the LunaPro is often too inconvenient to carry.
    My advice, chuck the Pilots and buy a new meter. As already noted, film and processing is not cheap.
     
    ] likes this.
  13. AJG

    AJG

    Is your Twinmate linear or is it inaccurate to varying degrees at different light levels? If it is linear in response then you could probably set a different ASA/ISO to compensate for the error. I know it is yet another thing to think about, but it might work.
     
  14. That's basically the conclusion I came to ... but we've got to say "Each to their own", some users may be happy with their Pilots, I'm happy with my Zeiss Ikophot and my Minett Type IX, both have Zero adjustment and are not far off exposure wise. My new Twinmate reads different to my Canon digital compact on Automatic mode by miles. The Canon has always been over-exposing and I find I'm using Manual mode more often on minus 1 1/3 or sometimes minus 2 ... the Twinmate exposure readings are where I want them, they seem slightly under-exposed and highlights are not blown out as the Canon does to them.

    I use the Canon to check all my light meters by setting the Canon to manual, set it to a light meter reading, take a shot of the same scene, then see what it looks like. From that, I get a good idea of what the film will be like when using the light meter for the film cameras.

    This is a reading from the Twinmate L208. I pointed it at the overcast sky and to my surprise it was sunny 16. The exif data in the Canon was ASA100 f8 1/400sec (only f2.8 and f8 is available at ASA 100 in the Compact, I used f8). There was not one bit of bright sunlight shining through those clouds and there was no distinct shadows anywhere.
    Sunny 16.jpg
     
  15. Both of those exposures are the same - 1/400th @ f/8 = 1/100th @ f/16 - and both are what's to be expected by pointing your light meter at an overcast sky. Remembering that light meters are designed to meter from a subject with an average Reflectance of 18% or thereabouts. That's 2.5 stops lower than the light that's incident on the subject.

    If the incident light is the subject, then obviously the exposure needs to be 2.5 stops less than that for something reflecting only 18% of that light.

    In other words: You don't get a 'sunny 16' reading by pointing an averaging reflected-light meter directly at the sun!
    That's just likely to end-stop the needle.
     
  16. I've spent two days testing the Twinmate L208. I set the digital camera to the same settings as the L208 and take a shot. The overcast sky is one of many different shots. There was no Sun to point the meter at, there was only thick overcast clouds, and the meter was angled upwards at 45 degrees. I check exif data of each shot because the "f" number can change even if I set the camera manually. For instance, some shots changed from f8 to f9, so the manual mode is not as "manual" as I thought.

    The Sekonic Twinmate is under-exposing if it's pointed directly at the subject, against the digital camera's meter reading. If the Sekonic is pointed down at the ground while taking a reading, just as I've been reading on the Net, the exposure improves.

    Sekonic Twinmate L208 match-needle reading, directly ahead ........... versus ............ Canon Digital IXUS 980 IS in-built meter reading
    Sekonic L208 exposure.jpg Digital's exposure.jpg
     
    Last edited: Dec 3, 2021
  17. I don't fully understand but to get correct exposure with a meter in reflective mode, you do need to point it downwards, that is, towards the part of the scene you want to be exposed correctly, i.e. the ground. If you point it towards the sky it will certainly underexpose the ground.
     
  18. Yes I'll be pointing the L208 at the ground, except if there is a white or very light colored building/object in the scene, I've tested the meter under that scenario too. The meter needs to be angled up from the ground a bit or pointed directly at the white building/object depending how large it is in the frame.

    I don't mind that the L208 slightly under-exposes, light colored objects are not blowing out and retain their detail, then if the shot overall is too dark, I go the the histogram and watch it as I move the "Exposure" slider to the right. The histogram then moves more to the "light" side and automatically adjusts the White Point at the same time. I watch the detail in the light colored objects and their "lightness" and don't move the "Exposure" slider any more than I have to. This is far better than trying to correct an over-exposed shot because a lot of the time detail is lost and the light color of the objects changes to pure white when it may have been a very light grey or light pink or something else. In Automatic mode, my digital compacts over-expose light colored objects 80% of the time. I'm not happy with that.

    I've just got to make all these testing guidelines work for my film shots now, and that will be my next test with this plastic Sekonic L208. It will require some pretty consistent developing and such, but I'm confident of doing that, with fresh chemicals, which I have here ready to be mixed.
     
  19. If forgot to say that both the L208 and the Canon digital were both pointed straight ahead in the same direction, to see what the comparison would be. Obviously the L208 gave a different exposure to the Canon, so for the L208's exposure to match that of the Canon's, it needs to be pointed at down at the ground, and that's what my tests revealed. I was trying to prove whether the posts I'd read on the Net were true or not. They turn out to be true, and I don't know why Sekonic didn't include it in the L208 instructions. My old Sekonic L98 had it in it's instructions, there was an illustration of a human figure pointing the meter down at a certain angle.
     
  20. When I first learned to use a light meter, I was taught to point the reflection sensor slightly downward from parallel, but not directly at the ground. That was to ensure that any strong back-lighting was minimized. For incident, I was taught to raise the meter to head level, and lock in the reading.
     

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