FSC curve w/o mask has the value difference between fsc=0.5 and 0.143

Hi all,
I obtained the final 3D map via local non-uniform refinement. The shapes of the FSC curve appear to be expected and good, except for an unmasked map.
The FSC curve without any mask has the value difference between fsc=0.5 and 0.143. (Please see the attached image.)
I’m not convinced whether it is in optimal and good.
If it’s abnormal, why is this? and how can I solve the problem?

I performed the local motion correction and global/local CTF refinement, then global non-uniform and local non uniform refinement.

Look forward to hearing from you!
Thank you.

P4_J383_fsc_iteration_005_after_fsc_mask_auto_tightening

Hi Joong,

It is normal for your unmasked FSC to be lower resolution. There is more noise contributed by the unmasked solvent region. This effect will become more pronounced at larger box sizes relative to your particle size, or for particularly elongated particles.

Cheers
Oli

1 Like

Hi Oli,

Thank you very much for your detailed explanation!
It would be so helpful for me and hope you have a nice day!

Thank you,
Joong