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displayed size of sun/moon

While trying to plan for the upcoming total solar eclipse, I found the relative displayed diameters of the sun and moon appeared to vary with zoom. When zoomed in at high power, first contact matched well for the specific location.But when I zoom out, it shows  significant overlap at first contact. I double checked and display moon/planet sizes were set at 1x.

This is with SSPro 5.3.0 macOS 10.12.4 on MacBook Pro 13 late 2016 Touch Bar.

BTW, why is the version number not displayed in the about SkySafari splash screen?


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    Bill Tschumy

    We, like most planetarium programs magnify the apparent size of the Moon and Sun when zoomed out.  Otherwise it can be very hard to finding the 0.5º circle in the sky.    I believe you need to be zoomed in 15º or more for this not to occur.

    If you are trying to estimate first, second, etc contact, you will want to turn off Atmospheres (and possible Surfaces) in the Solar System settings.  This will hide the sun glow and make the determination much easier.

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    Thanks. I did have atmospheres off. Surfaces off does brighten the moon a bit.

    A quick test shows the switch starts about 27.7 x 13.7 degree FOV, without the sidebar. About 21.8 x 14.3 with. So your 15 is close.

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