Match Total Exposures

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I just did a quick test in my LR 12.5 / Mac OS with six randomly selected photos, and Match Total Exposure worked correctly.  It set Exposure of the last five photos so that their Effective Exposure Value (EEV) matched that of the first photo:

"Second photo (the one that should have it's expose adjusted to match the first photo) gets its exposure set to 5.00."

That indicates the Exposure Value (EV) of the second photo was more than 5 stops less than that of the first photo. But the Exposure slider only goes to +5.

Three ways to verify the results of the Match Total Exposure command:

1. You can double-check the EVs and their difference yourself.  The formula is:

EV = log2 (aperture ^ 2 / shutterspeed) - log2 (ISO / 100)

For example, for an exposure of f / 5.6, 1/600 sec, ISO 160, the EV is:

log2 (5.6^2 / (1/600)) - log2 (160 / 100) = 13.52 (rounded to two places)

The difference of the two EVs is what the Exposure slider of the second photo should be set at.  

2. Or use the EV calculator:

https://rechneronline.de/exposure/

(Use a normal calculator to convert fractional shutterspeed to decimal, e.g. 1/100 sec = 0.01.)

3. Or post here the exposures of the two photos, and I'll calculate the EVs.  

4. Or, you can use the free trial of the Any Filter plugin to display EV and EEV, as shown above.