Spaceship based telescopes

[weby]

Originally Posted by David L Pulver

The main problem is I can't figure out a way to make HIGH TECH's suggestion of Telescopic Vision as high as 10-15 (up to 32,000x magnification) for TL7 spy sats work unless I made the scaling *linear* with magnification (Given that Anthony makes a good argument that t his isn't really logical, and about 9-10 levels is better, perhaps I shouldn't...) Square of 32,000 gets rather impossibly high...

I'll probably reluctantly have to say that in Vehicle Design at least the values are about half to 2/3 what HIGH TECH says. I don't really like to do that, but it has the advantage of actually better matching the numbers in SPACESHIPS and UT, so it's not really a retcon.

So If I want to use the basic GURPS rules without giving the +10 to see hidden objects that Anthony uses, I should then use what? Linear scaling?

[David L Pulver]

Originally Posted by weby

So If I want to use the basic GURPS rules without giving the +10 to see hidden objects that Anthony uses, I should then use what? Linear scaling?

I don't think there's a +10 to see hidden objects. Rather, there's a standard +10 to "see objects in plain sight."

Why you need it is kind of obvious if you think about it.

A human eye = 1x magnification sensor; it rolls against IQ to spot something. Average IQ is 10.

If range penalties are applied, there is a range penalty of -10 at 100 yards, which means you spot them on a 10 skill -10 = 0 or less. Oops. No.

I think most people will agree it is possible to see someone fairly well at a 100 yards (or even 300 yards) if it isn't concealed, so the +10 modifier applies, giving a spot chance of 10 at 100 yards and perhaps 4 at 1000 yards for a one-second search.

Similarly, a spy sat with 512x magnification (+9) with "in plain sight" (looking down on orbit into a parking lot, say) with a trained operator (14 skill) and +3 for a several seconds aim is therefore 14 + 3 + 9 + 10 (plain sight) - 32 (200 mile range for low orbit) = 4 or less to search around to locate something in a large area or 13 or less (double the +9 bonus for "zoom in") if you're looking at a known location like spying on a missile silo or someone's front door. (Actually, I expect the spy satellite crew probably has some software tools for contrast enhancement and the like which give another +2 or so, for a net total of 6 or less or 15 or less.)