Sunday, August 15, 2010

The Gossen Digisix - a very tiny external ambient light meter

Recently I came across the discussion of external light meter. Now, given that even 30-year old cameras have decent TTL-meters, there seems hardly a need for it. But then it got me thinking. What if your camera is 45 years old?

One solution is to just toughen it up and trust the old heuristics. There's the sunny-16-rule which states that on a sunny day you set your aperture to f16 and the shutter speed to the inverse of  your film sensitivity. This works quite well:

I should say it works well-ish. In the above, I was merely in the ballpark and the shadows could have done with half a stop of light more. I shot this with a Zorki-4, a Soviet Leica-clone from the 1950s. And I'm also not showing you all the pictures that turned out unusable, usually due to gross under-exposure.

A light meter would certainly take care of all that. But I want something that is small, light and convenient to use. Otherwise, the precious light meter just ends up being like my tripod - seldom used. It turns out that I have found the perfect little light meter: the Gossen Digisix.

It's very small and weighs nothing, just one and a half ounces. I attach the long strap to a belt loop and stick it into the pockets of my trousers. More importantly, it couldn't be easier to use: the little white ball on top knows two positions. If it's centered, as in the above, it takes incident readings. Move it 45 degrees to the right, and it's now a reflective meter useful for scenes where your subject is in a different light than yourself.

You set the ISO sensitivity by keeping the lower red button pressed until you hear a tone and then use the upper button to toggle through the ISO values. This one goes from ISO6 to ISO3200 in third stops, very nice. A reading is done by pushing the upper button and it displays the EV number, plus a black dot per third. So in the photo here, it would indicate an EV of 6 2/3. You can now turn the white ring to match up the EV and you can read aperture/shutter-speed pairs that you can dial in on your camera. The whole process takes two seconds.

And if the scene allows you to use incident meter-readings (which many will), you win again as this type of light measurement is immune to all those things that would normally confuse a camera's reflective meter, such as strong back-lighting. It therefore saves you the occasionally error-prone process of exposure compensation. It also has a few other convenience functions, such as a clock, a timer and a thermometer. It can also be used to gauge the contrast of a scene although I am not sure how well that will work without a spotmeter.

With this meter, I'll be much more likely to take out some of the cameras I've been avoiding recently. It will finally allow me to take off the heavy TTL-metering viewfinder from my Pentax 6x7 and replace it with the much lighter, un-metered folding hood that will allow me to shoot sneakily from the hips instead of pointing a four-pounds contraption at people.

What the Gossen is not is a spotmeter. I have a Sekonic L508 which I use at home for my little macro studio to meter off a gray card. That meter, while it allows you to calculate the trajectory of a rocket you send to the moon, is way too big and complex to take it outside. The Gossen however is perfect for the other scenarios and it'll reward you with perfect exposures every time:

I took the above this morning with an ancient Pentax SV on Ilford HP5+, downrated to ISO200 and pulled one stop during development in HC-110. The camera is 45 years old but still extremely competent, especially once the metering problem was solved.

The Gossen will set you back around $135 if you get it from B&H. So it's not exactly cheap but it does open up three to four of my cameras that have seen less use than they deserve. That makes it a small price to pay in the end. And finally, here's another photo of the meter, leaning casually against the aforementioned Pentax SV:

Did I already say it's tiny?


  1. Nice review. I have seen these in ads and wondered how good they are. I don't need one at present, but have considered buying several older cameras if I do, this sounds like an excellent meter to use with them.

  2. Yes, it's well worth a consideration. Its biggest benefit is that you will take it with you and use it.

    I've heard some reports about the strap loop on the meter being not very sturdy and breaking for some people. I could still have it in my pockets so it would only be a minor nuisance.

  3. Totally agree that it's a very good and accurate meter. When it's around my neck, I hardly ever know it's there. It's used 99% of the time on incident mode. Very well worth the money...