OpenNeuro ds001110 func images are different lengths

I’m working with the Sherlock_Merlin dataset and have noticed that for the MerlinMovie stimulus, the corresponding functional images from different subjects range from 1026 to 1041 1.5s TRs in length. (difference of 22.5 seconds)

Does anyone know what could account for this or where I might find more info to align these? On openneuro it says that the data is cropped and that to me suggests they should all have the same length or at least be closer than this.

from openneuro description:

The data needs to be cropped from the beginning and the end to be aligned and matches the onset of the stimuli.

Cropping info (in seconds, NOT including HRF delay):

viewers:
Merlin Movie: start 25.5 end 1528 (matching stimulus file: Merlin.mp4)
Sherlock Movie: start 25.5 end 1441 (matching stimulus file: Sherlock.m4v)

Note: the crop at the beginning includes an eye tracking set up and scanner delay.
The cropped data will include all the movie data, including the cartoon intro.
Depending on the research questions the movie can be time stamped and cropped further if needed)

Hi @jsmentch

Unfortunately, I am not positive on an approach to resolve - perhaps it may be beneficial to reach out to the dataset owners for clarity?

Thank you,
Franklin

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