Hello Andreas!
Hello,
My question is mainly for those who own an Analyser Pro. My question is: the instruction manual states that the calculated exposure time is based solely on the brightest part of the negative, i.e. the shadows?! So I take the measurement first on the bright parts of the negative and then on the dark parts (highlights). On the other hand, however, everyone always says that the Analyser Pro calculates the exposure time from the highlights and the gradient from the shadows? Which seems more logical to me! I have a German manual; perhaps there is a mistake in the translation. And when testing the paper speed, I have to take a measurement without a negative, with the enlarger set to maximum magnification and the aperture stopped down. The time should be between 10–20 seconds. For me, the time is 4–5 seconds and I don’t have an ND filter! On my device, there were no preset values saved in the paper channels. Could that be why such short times are resulting? And that a time of 5 seconds is then OK?
Many thanks
Andreas
I have that model, but which one do you have?? A new one??? When brand new, the values for the speed of the gradients in all paper channels are all set to 0, because the values to be entered are simply the deviations of the actual speeds of a particular paper type from the underlying standard, namely Ilford MGIV. However, the ISO-R values for MGIV are already stored for PAP1; if not, then someone has deleted them (set them to 0).
Now to exposure metering: The device itself does not know which pixels you are measuring during a single reading, but always assumes that these are the brightest highlights (not to be confused with the highlights!), i.e. the areas of high negative density. The measured area of the image would therefore appear as the lightest grey in the image if you follow the exposure time suggested by the device (assuming correct calibration). However, if you measure different areas of the image one after the other, the device naturally detects which of these was the darkest and bases its exposure time suggestion exclusively on that single measurement. On the display, however, the illuminated LEDs give you an indication of where the other areas you have measured fall on the brightness scale.
Because the device also briefly displays the measured relative density with each measurement, i.e. the density of the measurement point compared to the density of the very first measurement point in a sequence, the instruction manual suggests measuring a very thin area of the negative (i.e. a deep shadow) as the very first measurement point in a sequence, because only then do the displayed density values make any sense at all. However, as early as the second measurement in such a sequence, you will be measuring a very dense area, which will then provide the suggested value for the exposure time. If you’re not interested in the densities, you don’t need to stick to this.
To test the paper’s speed: the paper couldn’t care less which timer controls its exposure; it has its own speed, and that’s that! You just need to work out how this speed differs from that of the MGIV, in terms of +/-1/12 stop increments. What is actually recommended is a raised VG head and strong stopping down, so that the MGIV suggestion determined by the pre-calibrated device (for the lightest grey, see above) falls within a time range that still leaves a few stops of leeway downwards for papers even more sensitive than MGIV (there won’t be many of those....). Incidentally, this is still the case even with a measured 5 seconds, although one might naturally suspect that you either have an incredibly bright VG head or that not all the controls in the paper channel used are set to 0 after all. Ultimately, you need to get the analyser to show you the correct time for the lightest grey with this paper – you’ll be able to see for yourself whether you’ve managed it in the end.
Good luck, Karl
