Gossen Luna PRO S Battery Replacement Kit

[marke]

I'll say it again, to anyone who is questioning my decision to try a Luna Pro. First, as I understand it, the Pro is supposed to be able to read in less light than the other meter I picked up, the Luna Lux. I have no idea how the newer Pro sbc version (w/9v battery) compares in size to the older Pro model, but the Luna Lux is WAY bigger than the older Pro model. So that's on reason why I wanted to consider the Pro model.

Last night I made a shim out of a 35mm plastic film container, so that 675 zinc air batteries would fit into the Luna Pro. The shim seems to work. Unfortunately, it doesn't seem like the battery test is giving me a good reading. I tried two different sets of batteries, and the needle doesn't get anywhere near the red check mark. Anybody know what I'm doing wrong?

 

[Gumby]

... the battery adapter solves the battery size problem, but not the battery voltage problem.

You must have got a defective unit, amigo... mine reduces the voltage AND solves the battery size problem.

 

[plummerl]

In order to reassure those with (or considering) a Luna Pro (non S or S), the adapter is the "circuit modification"! It works with both meters. This adapter has a built in circuit to adjust the SR44 voltage to the same as the original mercury ones, that both the Luna Pro and Luna Pro S (LunaSix 3, 3S for Europe) used. Trust me, I have the adapter and have measured the voltage with and without the adapter. 🙂

 

[venchka]

...Last night I made a shim out of a 35mm plastic film container, so that 675 zinc air batteries would fit into the Luna Pro. The shim seems to work. Unfortunately, it doesn't seem like the battery test is giving me a good reading. I tried two different sets of batteries, and the needle doesn't get anywhere near the red check mark. Anybody know what I'm doing wrong?

Maybe. Not positive. The zinc-air batteries need 24 hours to get up to full capactiy.

 

[capitalK]

Haha I realized I read the manual wrong... I should be reading from the yellow triangle not the green circle. It's much closer now, though still not perfect.

 

[marke]

Maybe. Not positive. The zinc-air batteries need 24 hours to get up to full capactiy.

Thanks, I wasn't aware of that. I should be able to hear better then too, right? 😉

 

[Nokton48]

Actually I'm finding this thread interesting, and eventually, relevant for me. I have two of the original Lunasixes, actually they are the SINARsix by Gossen. Need to dust them off, and get them going again.

EDIT: I have three new CRIS adapters, I just opened one up. It takes an Eveready 386 silver, so I just did a quick test. I have an original 1.35V in my Leica M-5, so I centered the needle, removed the mercury battery, and replaced it with the CRIS/386. Meter needle is giving an identical reading with the replacement. COOL.

 

[Papa Smurf]

hear aid batteries

hear aid batteries

I'll say it again, to anyone who is questioning my decision to try a Luna Pro. First, as I understand it, the Pro is supposed to be able to read in less light than the other meter I picked up, the Luna Lux. I have no idea how the newer Pro sbc version (w/9v battery) compares in size to the older Pro model, but the Luna Lux is WAY bigger than the older Pro model. So that's on reason why I wanted to consider the Pro model.

Last night I made a shim out of a 35mm plastic film container, so that 675 zinc air batteries would fit into the Luna Pro. The shim seems to work. Unfortunately, it doesn't seem like the battery test is giving me a good reading. I tried two different sets of batteries, and the needle doesn't get anywhere near the red check mark. Anybody know what I'm doing wrong?

I use size 10 zinc air cells in my hearing aids plus the large ones in one of my two Luna Pros. ( I love how sensitive they are plus the adapter for spot reading is great.) My experience is that the larger zinc-air cells are especially prone to having "dried up" in the container before they are ever activated. The size 10s can do that too, but sales on that size must be brisk enough for the problem not to be that much trouble. What I do is to activate the cell, wait 10 minutes or so and then test it with a DVM. I will test three or four of the larger ones before I get two that read about 1.4v. They are not cheap and the added aggravation makes me think that I need to order another CRIS adapter or maybe have one of my Luna Pros recalibrated for the silver oxide batteries?😕

 

[Papa Smurf]

Thanks, I wasn't aware of that. I should be able to hear better then too, right? 😉

Maybe they do need 24 hours to become fully active but, as I stated in an earlier post, I wait about 10 minutes and test them for voltage. None to date have increased in voltage significantly after waiting a day or two to not warrant just throwing them away. Therefore, I just wait 10 minutes or so and test with a DVM.

 

[venchka]

I can put all 3 side by side

I can put all 3 side by side

Well, I appreciate your experienced input. I wish I had become more familair with the 3 different models discussed here beforehand. One question I still haven't had answered is whehow the size of the Pro sbc compares to the original Pro and the newer Luna Lux sbc. The Lux is considerbly larger than the original Pro, and if the Pro sbc is about the same size as the Lux sbc, is there any reason for me to even consider looking for a Pro sbc. For example, I had heard that the original Pro is more sensitive in low light than the Lux. If so, how does the Pro sbc compare to those two?

RFF member wclavey and I between us own all 3. Next Saturday we could put all 3 meters to a test and measure them. Westley may have all 3 and can compare sizes before next Saturday. I'll ask him to check in.

Personally, after using a Weston Master V and original Luna-Pro since forever, I genuinely prefer the null meter reading Luna-Pro sbc. It's super easy to read shadows 1 or 2 stops under and compare to highlights 1 or 2 stops over and make a perfect exposure. The meter can be locked on too for continuous readings. No doubt it may be bigger. It's also better. When new, the silicon blue cell was the meter to have. A big improvement over the Cds cell.

A little google helps:

Specifications


EV Range ASA 25 - 6 + 15

Response Time 1/1000 Sec.

Photo Cell Silicon Blue Cell

Angle of Coverage 30' Reflected 180o Incident

Sensitivity 016 to 32,000 footcandlesin one range

Power Source 9 volt Eveready Battery - or 9 volt Mallory Duracell O Alkaline Battery or equivalent.

Battery Type #M N1604
Dimensions 43/4x13/4 x23/4

Weight 81/4 oz. with battery

Scale Ranges:

Cine Range 4.5to144fps.

Exposure Value Range -8 to +24

Shutter Speeds 1/4,000 Sec. to 8 hours

Lens Aperture f/0.7 to f/128 Exposure Factor Scale ... Plus/Minus exposure indicated in EV; Plus exposure indicated in Exposure Factor

ASA Range 0.8 to 100,000

The manual is here:

http://www.butkus.org/chinon/flashes_meters/luna-pro_sbc/luna-pro-3.htm

 

[venchka]

Phsyical size measurements. We already now that the sbc based meters outperform the Cds cell meters with fresh mercury batteries.

 

[gdi]

I have an old Luna Pro and an SBC. They are basically the same size and take the same spot attachment. The SBC is more square than the older one.

I modified my old one to drop the Silver Oxide voltage down close to the Mercury cells (there are instructions in the forum - you can see it here (courtesy of ChrisN) - > http://www.rangefinderforum.com/forums/showpost.php?p=318294&postcount=23

You have to watch the batteries as the voltage drops - but I found that as long as you run the Battery Check now and again it works fine and is very close to my SBC.

Correction - I just laid the SBC beside the Luna Pro an the SBC is significantly longer and thicker.

 

[venchka]

Shall we agree...

Shall we agree...

...If anyone has held an older Luna Pro and a Luna Lux side-by-side, you will know what I'm talking about when I say that the the older Pro is easier to handle.

...to disagree? Of the 3 Gossen meters I have used over the years, the Luna-Pro sbc is the easiest for me to use.

Is the Luna Lux the model with the null setting LEDs? 😀 If so, Westley Clavey bought one to repace his Luna Pro sbc. He immediately tried to trade with me for my Luna-Pro sbc. No deal. I'm an analog guy. Love swinging needles.

 

[lmd91343]

You must have got a defective unit, amigo... mine reduces the voltage AND solves the battery size problem.

Ditto...

I have two of those battery converter units!

 

[lmd91343]

I just tested my hand held meters in dark conditions. They are all calibrated and match each other in normal daylight and very low light.
Here are the results at asa 100:

Sekonic 488 spot EV 1
Sekonic 308B EV .5 (I don't know spec)
Soligor spot SP1 EV 2
Soligor spot SP2 EV 2.33 (1/3 stop less than spec)
Gossen Luna Pro EV -4 (with gossen battery converter)
Gossen Luna Pro S EV -4 (with gossen battery converter)
Gossen Luna Pro F EV -2.67 (1/3 stop less than spec)
Voigtlander VC2 EV 1

I like the fast response of the Luna Pro F over the Luna Pro(S). The Luna Pro(S) is a little more than 1 stop more sensitive than the LPF, so it will work in half the light. If I need that extra meter sensitivity, it is usually a big deal for me(tripod, weights, cable release, red flashlight). The LPF is larger and more angular than the LP. I like the way to read the needle on the LPF than the LP.

I believe the Luna Pro SBC is the same as the Luna Pro F without the flash capability.

The LPSBC is spec'ed at EV-6 at asa25 that would be EV-4 at asa100. The LPF spec lists the lowest sensitivity a EV-3. I measure it at EV-2.67. That leaves a difference of 1 stop between the two meters.

The LPF is functionally quicker and easier. The LP(S) is smaller, more sensitive, and more rounded. That extra stop at the low level of light is so rarely used, I'll take the LPF unless I thik I might need the extra low light stop. Last time I checked prices a LP can be found for $30 and the LPF for $125.

I find myself using the LPF more often than the LP(S). If I go without a camera bag I will take only the 308B or the VC2!

Thanks, but as I stated in an earlier post, I already have this meter, along with the older Luna Pro. Since I had heard that the older Pro can read in less light, and the fact that it's considerably smaller than the sbc models, I still wanted to consider the older Pro.

I don't think anyone has yet answered my question: Is the older Pro able to read in less light than the newer Pro sbc?

If anyone has held an older Luna Pro and a Luna Lux side-by-side, you will know what I'm talking about when I say that the the older Pro is easier to handle.