The standard of the photo finishing industry for years, MacBeth TD series transmission densitometer. Thousands of dollars when new, you can get this one for a fraction of the original cost. I have two units and selling this one which was my primary until I got a TD504.
This model is from the late 70s, and works as designed. Uses 110v standard outlet. Comes with the original manual from MacBeth. Photos show condition- used but never abused.
Why would you want one of these units? Zone system users want to calibrate their personal film speed for b&w films. This is the tool you use to get you that information. Personal ISO = .8-.10 above base + fog.
Measure B+F, densities of negative high values, compare your development times - I measure the fogged portion of each roll of 35mm to determine how developer activity.
$165.00 USD
Price is USD $125 unit + $40 Shipping FEDEX Ground, US 48 states only.