AP: Image stacking reduces exposure?

[wjgo]

I stacked 17 raw files, and used median, and mean.  The resultant image is much darker and any of the images in the stack.  Is this to be expected?  These are exports of the stack, and an export of a raw used in the stack.  I might expect the water to become darker, averaging pixels, but the stream/river bank is also much darker, even the light grey fence.

 

 

Edited February 5, 2018 by wjgo
minor edits.

[wjgo]

OK.  I think I know what happened.  AP shows opened raw images with one exposure, and when exported to a tiff, it has a much lower exposure.  And exported .tiffs do match my results.

I am mostly new to AP, so what is the best workflow for this?  Use the raws, then edit the resultant .tiff or convert the images to .tiffs first - and then stack them? 

But, both Lightroom and DxO export to .tiffs from raws, a much more acceptable exposure level, and far closer to what I saw through the viewfinder.  What is going on.  If Ap somehow not exporting .tiff correctly?  Will exported .tiffs from AP loose dynamic range if its from an already dark raw file?

[wjgo]

It seems to me what is happening is that AP is not batch converting raws correctly.  I can export a .tiff from a raw and get a good exposure.  But if its in a batch job of converting a folder, (using 16 bit), or a conversion that takes place in a stack, the exposures are way too dark.

[stokerg]

Hi wjgo,

 

This is expected behaviour for the time being. More information about this can be found in this thread: https://forum.affinity.serif.com/index.php?/topic/37992-bug-raw-development-after-batch-processing-raw-jpeg-pictures-are-too-dark-pictures-dont-look-the-same-as-the-raworiginal/&do=findComment&comment=204163