Craig:(posted 8225 days ago)IMHO save your money and get a 21 step tablet with a wide range of densities on it and comapre the negs visually. You may be surprised at how close you can come by eye if you have standards to go by. Also, Kodak publishes a reflection "densitometer" that is a cardboard sheet with spots of varying density with holes in the middle to put over sections of your peint -paper white to solid black in about 21 steps. Thse two tools make desnstomery simple and cheap. Besides, with any photo-electronis device, it must be calibrated agains a step tablet periodically as all sensors drift.
I had the use of McBeth Densitometer and it was not worth the hassle.
If you really need one to find Zone 1, then go to a pro lab and ask them to measure it for you. They will maybe even do it for nothing if you're a customer- thats how I used the McBeth.
Cheers