A comparison of three colour meters
Just in case anyone is wondering which colour meter to choose:
When Minolta stopped production of the Color Meter IIIF I began to be asked about how the Minolta IIIF compared to the Gossen Color-Pro 3F. I had no experience of the Gossen, so decided to get one and find out. That meant that I had three colour meters: the Minolta II (MII for short) and IIIF (MIIIF for short), and the Gossen (G3F for short). I've never seen a comparison of the three, so thought that it might be worth making a few notes.
eBay prices: about $300 or less for the MII, and about $800 for the MIIIF and G3F.
The MII is the most basic of the three meters. It only measures continuous light in its standard form. A separate flash receptor is available. I don't have one of those, so can't comment on it. I'd be grateful if someone else added their experience of it.
The head is removable, and can be located remotely from the body of the meter with a ribbon cable. I have one of those, but have never found any reason to use it. There's a standard 1/4" tripod thread on the head, so you could put it on a pole to get extra reach while holding and reading the meter body. The head does not rotate, unlike the other two meters. I've never found that to be important. Mine can read in slightly lower light levels than the other two. It has three preset film types; daylight 5500 K, Type A 3400 K and Type B 3200 K. There's also a variable setting.
It takes a 9 V battery, and the blade contacts are built into the side of the battery compartment. This is a robust, quick system - I wish that all PP3 connectors were that good.
It displays colour temperature, reciprocal megakelvin (MKˉ¹ = mired) shift and a green-magenta index. There's a table on the back to convert from mired to Wratten filter numbers, and from the G-M index to CC-G and CC-M filters. For example an index of +8 corresponds to CC20M and an index of -7 corresponds to CC20G. The index display resolution is 1, so this means that you can estimate the reading to better than the nearest 2 CC units. In practice that is a reasonable expectation for the accuracy of this meter: plenty good enough.
I'll cover the other two meters feature by feature.
Batteries: The MIIIF takes two AA cells. Simple. The G3F takes a 9 V battery
but has one of those flimsy connector pads on a thin bit of wire. Gossen could do better.
Range: The G3F comes with two flat receptors [colour meters always have flat (cosine) receptors instead of the domed (cardioid) type usually found on light meters]. One receptor has a semi-silvered mirror that decreases the sensitivity by five stops. Lose the attenuating receptor and it will cost $125 to replace. Lose the normal one and it will cost you $24 to replace. The MIIIF has a range switch.
Flash: they both have good flash/continuous functions, and a sync socket. The G3F will give the flash output in lux-seconds, and the gate time is adjustable.
Display: they display similar information. MKˉ¹ shift, Wratten filter, CC adjustment. The G3F gives lux as well. But here's the thing: the G3F only gives the CC adjustment in steps of five, while the MIIIF gives it in steps of one. No big deal, because who carries CC filters in steps of less than five? I carry them in steps of ten when I'm travelling light. If I get a reading of five, what do I do? In fact it doesn't lead to a significant average error, but the MIIIF has a definite advantage. Even if the absolute accuracy of the two meters is similar, the extra resolution of the MIIIF can give it an advantage.
Size: the G3F is the smallest of the three. The MIIIF is slightly smaller than the MII.
I hope that gives a general idea of the differences between the meters. If there is anything specific that you would like to know, just ask. In case you haven't guessed, I think that the MII is great value if you don't need the extra functions of the other two.