Zone System help with Luna Pro "F" and spot attachment

I'd appreciate some advice on using a Gossen Luna-Pro "F" meter with

the variable spot attachment.

 

I've used this meter for many years as an incident meter. Both with

flash and without on chromes, this meter is dead on for this type of

exposure metering.

 

The vari-spot attachment has two colored circles in the viewer, one

green and one red for the corresponding angle of view. I think I

remember that the old Luna Pro SBC meter has a green and red

compensation scale on the meter body to assist using the vari-spot.

 

Will the "F" meter require any compensation to accomodate the vari-

spot attachment OR do I read the exposure direct?

 

Example:

 

Let's say that reading through the vari-spot attachment, reading the

7 degree circle (which BTW is tough when wearing reading specs), on a

shadow area will read the shadow as zone V (which of course it's

not). I'll "place" that reading at zone III (2 stops less exposure)

and see where that reading "places" the highlight. Let's say that the

highlight "placement" is zone VIII. My information is that all should

be well for "N" delevelopment. If the highlight reading is zone IX

I'd give it N-1. If the highlight reads zone VII I'm going for N+1.

 

Again, do I read direct exposure or make some additional meter

compendsation for the attachment.

 

I realize, of course, that other camera, lens and film considerations

are additional to meter readings.

 

Thanks for your assistance.

Steve,

 

For a highlight with textural detail, you want that highlight to fall on Zone VII, not Zone VIII. If it falls on Zone VIII your indicated development is N-1, If the highlight fell on Zone IX then a N-2 development is indicated.

 

The range of Zones is "inclusive", not differential. For example...Zone 3, 4, 5, 6, 7 is 5 stops,(count the number of zones) not 4 stops as 7-3 might seem to indicate. The reason for this is that each Zone repreesents an entire stop of tonal change, not a single point on a grey scale. The darkest part of any zone is almost a stop darker than the lightest part of that zone, it's a continous grey scale.

Yes Steve, you need to compensate when the vari-spot attachment is in use. 15 degrees=EV+1; 7.5 degrees=EV+3.

To add, I have the same setup and yes it is dead on! If you look at the back of the spot attachment, you will see +1 for 15 degree and as I recall a +3 for the 7.5... Looking at the front of the meter, you have your dial where you turn to null the needle. Well, on that dial you will see numbers on the upper part of the dial. This will turn. You can hold the dial and independently turn the inner dial. You have a small notch that should normally rest on "0". Turn this to +1 and you have your correction for 15 degree. Now turn it to +3 and switch the little lever on the spot attachment to 7 dgree and you are set to use the 7 degree properly. If this isn't helpful, I can take some digital pictures and email them to you.

Cheers,

Scott

Steve

 

You should do a calibration test with that meter before you do anything else. Nobody knows what it is doing regardless of what the manufacturer says it does, and especially so with YOUR methods. Meters and ISO ratings and normal developments come from very controlled lab conditions that have nothing to do with your conditions. Best to start out with a maximum black for minimum time test for the paper you will be using, then do a zone 1 (iso) test, and then do a development time test. Then you will know what YOUR meter does with YOUR methods and the rest of YOUR equipment.

 

Kevin

Thank you, thank you, to all of you. Great infomation.

 

Learning more all the time.

 

Now I need to get stronger reading glasses to better read the little tiny numbers on the meter.

 

HHHMMM.

 

-Steve