For the two tests mentioned here, it does not matter they all work equally well. I might go for the LED one, but really whatever you can get for less than $100. Even an enlarger will work. These ESECO units list for $750 but we got them for $25 on ebay.
Originally Posted by Dismayed
For "Beyond The Zone System" testing; I don't know. You have to buy into that system and it involves (from what I gather) matching paper to negative with the curves. I'm not a fan of that method of working but that is not to say it is not a good system or that people should not use it. I have used multigrade paper and variable filtration since 1974 and prefer working the negatives up as I print them with trial and error. Also, I don't have the workbooks or software for the system, so I can't test it with these sensitometers.
If I were to take a guess, I'd say that none of these units will work with that system because some of your photographs will be at exposures longer than 1 second or shorter than 1/1000 second. None of these 4 units duplicates how your film in your camera responds to daylight scenes one might photograph. Again, that is just my guess and someone should test how that system responds to different sensitometers. Of course the reflection densitometers used for reading the paper will be a whole other can of worms. I don't own a reflection densitometer and have turned them down when offered to me for free. I don't think they are very reliable at reading the glossy photographic papers I use. They are designed for the graphic arts industry.
Last edited by ic-racer; 10-21-2012 at 09:18 PM. Click to view previous post history.