Question about astrometry parameters - by: klaus

I tried to solve an image with offline solver from my ASI 120 MM camera and thus switched from SBIG CCD to ZWO ASI (alignment tab) but the solver looped forever. When I try

~/bin/astrometry/bin/solve-field --no-verify --no-plots --no-fits2fits --resort --downsample 2 -O -L 14.6964 -H 21.6578 -u aw -3 291.579 -4 3.15167 -5 10 delta-aql-5sec.fits

the solver runs for minutes until I kill it.
But

~/bin/astrometry/bin/solve-field --no-verify --no-plots --no-fits2fits --resort --downsample 2 -O -L 33.6 -H 44.9 -u aw -3 291.579 -4 3.15167 -5 10 delta-aql-5sec.fits

solves the image within a few sesonds.

The only difference are the -L and -H parameters. How are they computed?

Klaus