Gossen Luna Pro light meter

[mario_henriquez]

<i>Why don't you just go to a Batteries Plus store and buy either the Kodak or Duracell direct replacements for the Z625PX? They sell two for $9.00. I bought mine in one somewhere in Arizona as I was driving through.</i><p>I already got them. They're working now.<p>Thanks all for your help.

[christian_odell1]

I've had a Gossen Luna Pro for years. Mine was made in 79 if I remember right. It's a terrific meter. I really need to get a flash meter with a PC port, but I've always resisted because I love my LP so much. You got a terrific meter.

[frank uhlig]

Ok, one sideways question: why do you need a lightmeter, or put another way: what kind of camera are you using?

 

And secondly, will you not also need a flash capable meter, given that you use a non metering camera?

 

Just a few thoughts. Mess around with them and see what you can make of them to whom KEH "shouldn't have sold

me, a beginner (and he knew it), such a "cumbersome" light meter." (quoted from your post) A self-pronounced

beginner with a professional lightmeter, what gives, Mario? Sorry, be mad if you need be, but be good as well,

please.

[dan_b.4]

The simple answer is to return it. Having a hard time gettting batteries, or having to buy an adapter you didn't know

about, are both legitimate reasons to return it.

 

 

The adapter that Gossen (sold at both Adorama and B&H) makes for the batteries actually is cheaper than buying

two CRIS adapters, which you would have to do if you went the CRIS route

 

I still haven't found a definitive answer on whether the Gossen adapter actually steps down the 1.5-volt batteries to

1.35 volts. If anyone has a definitive answer on this -- i.e., some kind of literature from Gossen, or maybe you're

handy enough to know how to measure the voltage through the adapter, or even if you have measured the adapted

meter against another meter you know to be accurate -- I'd like to hear from you. Otherwise, please don't quote what

you've seen on other posts (they're definitively contradictory) or suggest I look on the Bogen site (there's nothing

there about the adapter).

[jamie bushley]

I saw someone on ebay recently who had a bunch of the old (now illegal) mercury batteries for sale for around $3 each. I don't know where he got them from but that would be the easiest solution and they should last for years. I'm not sure if it's illegal to buy them, but I do think hes not supposed to sell them, but hey, we need them, so get um while you can!

[mario_henriquez]

<i>Ok, one sideways question: why do you need a lightmeter, or put another way: what kind of camera are you using?

</i><p>Mamiya RB67.<p><p>I found the batteries. The suckers are about $9.95 each. I'm still mad at KEH, but I'm going to keep the

meter. I don't want to deal with returning it. I got it for about $39. Hopefully it won't break down. I'm testing my Mamiya, that's why I got

it. I have to figure out how to use it now.

[ken_rosenbaum1]

I have two of the Luna Pro meters for use with my many old Pentax screwthread cameras. I have a small stock of

mercury cells that I mainly use in old Canons. I also have two of the Gossen battery adapters. They are exactly the

same as the mercury cells when I use them in my camera with the cheap, easily found SR44 batts. Two CRIS

adapters may not fit in the battery chamber. I also have a Gossen Super Pilot, a great meter that uses only one of

the old mercury cells. My preference is the Gossen adapter for the Luna Pro.

[paul_goutiere]

I have a old Gossen Lunasix 3. Similar to your meter. It takes two PX625 batteries.

 

The silver version of the PX625 battery is available from different sources on the net. MD battery seemed like a

fair place, and I received a pack of 6 PX625s for 16.95 plus shipping. (DO NOT USE THE ALKALINE VERSION OF THIS

BATTERY.)

 

I opened the case of the meter and installed a 1n914 diode in the + lead coming from the battery compartment.

There are two ways to do this, one is wrong, so experiment. Being able to solder is important. This operation

took less than 15 minutes. When the battery test button thingy is pushed the needle of the meter hits the "OK"

mark.

 

There is nothing special about the diode other than it is plentiful and has the right characteristics. I

purchased a package of them and I may have been ripped off a bit by paying about 95 cents for 50. Try Radio Shack.

 

The whole effort cost somewhere around $3.00 and 15 minutes.

 

I was so pleased that this worked so well I then did the same to my crusty old Weston Ranger 9 meter and a

Olympus OM1.

 

Yes, the meters are accurate and when the batteries go dead in a few years I'll simply replace with another

silver battery.

 

Paying all that money for an adaptor or adaptors seems a little expensive, as well, the batteries can be very

expensive if purchased from the local drug store!

[lookupinwonder]

I have a Gossen Lunasix. Same problem.

 

I got a homemade adapter for it (two actually), that will take SR44 silver oxide batteries (DO NOT use the LR44 alkaline variant). Works perfectly.

 

Look also at this link: http://www.buhla.de/Foto/eQuecksilber.html

 

There are several sources where you can get them if you don't trust your DIY skills. I can't find where I got mine though... but they were 15 euros each. Makes 25 for the meter + 30 = still only 55 euros for an excellent meter.

 

Please be aware that using 'equivalent' alkaline batteries in your meter, you will get readings, but they will be inaccurate. You MUST use silver oxide batteries.

[gary_watson]

Look, unless your film and processing are free, sideline the relic and get something newer that swallows AA batteries.The "adapters" outside the CRIS products just sleeve the smaller silver cells into the old PX625's home. The Sekonic 318-328-308 meters are all over the big auction site and usually don't fetch huge $. Just do it and get shooting, OK?

[ray_owens]

<p>SPECIFIC INSTRUCTIONS FOR SOLVING YOUR PROBLEM ON "GRAPHIC FUSION" BY SARAH FOX.<br>

<a href="http://www.graphic-fusion.com/lunapro.htm">http://www.graphic-fusion.com/lunapro.htm</a><br>

IF YOU NEED MORE INFO, JUST CONTACT ME AT : <a href="mailto:rayowens2007@gmail.com">rayowens2007@gmail.com</a></p>

 

[tom_thumbnail]

<p>The Sarah Fox fix requires another meter to calibrate the Luna with. That could be a problem.<br>

The Gossen battery kit costs $40 at Adorama. http://www.adorama.com/GSLPSB.html<br>

Is that for an adapter and two batteries? Once that is purchased, can just batteries be purchased as required later, or is that kit required whenever new batteries are needed? </p>

[peter_simpson1]

<p>Paul's suggestion of adding a diode in series with the + lead is definitely the way to go. Although I would make one small change: the 1N914 has a rated voltage drop of 0.6V to 1.0V. That's a bit more than we want (3V - 2.7V); we'd be better off using a Schottky diode with a forward voltage drop of 0.4V, like an SD-101 or 1N6263. Pretty much any Schottky small signal diode that will fit, will do the job. Less than a buck at Digikey.</p>

[mercedes_schrodinger]

<p><em>The "adapters" outside the CRIS products just sleeve the smaller silver cells into the old PX625's home.</em></p>

<p>No, they contain a diode that produces a constant 0.4V drop, reducing the effective voltage of two 1.55V batteries to what you would get with two 1.35V mercury batteries.</p>

<p>As for the "warm-up" period of the other batteries, this is completely true. Virtually all batteries work by an oxidation-reduction chemical reaction. Zinc air batteries, which have a potential of 1.4V, work by using actual oxygen in the air to oxidize the zinc. It takes from 5-30 minutes for the air to react enough with the zinc for the battery to get up to the correct voltage. It's this reaction that reduces their lifespan, since they keep reacting with air whether or not you're using them (unlike regular batteries, where the oxidizer and reducer only react when there's a complete circuit, with electrons flowing through, give or take a small trickle charge that can deplete some batteries during storage).</p>