Moar stars!

[dav1d]

I was having a play with my spanking new Revelation 5x on a 25mm EP last night, blowing up the planets & checking out random objects in the sky, during the brief breaks in cloud cover, when I noticed an odd thing - The Barlow revealed more stars to my eye than I would be able to see without it. Viewing just through the EP or without the Barlow & they're just not there at all.

I don't know how this is possible as the same amount of light is bouncing off the mirror and ending up in my eye as when I don't use it. Surely I should be able to make out these stars with my un-Barlowed 10mm, or even see them brighter?

Is it likely to be just my imagination, or is there something arcane going on which I don't yet understand?

PS & unrelated: No pics of anything last night as setting up the camera adapter in the dark proved impossibly difficult. I need to either set it up in daylight & hope it doesn't rain, or wait for a moon to help get everything lined up.

[sologuitarist61]

I guess it is 6 of one and half a dozen of the other - with the barlow fitted you lose some light but then again you are increasing your magnification so in theory seeing less bright objects as well

[Peter Drew]

Higher magnification darkens the field background which allows fainter stars to be seen, it might also show that some of the original stars were doubles.

[dav1d]

So it's a contrast thing? That makes sense. Thanks guys!

[acey]

Higher magnification darkens the field background which allows fainter stars to be seen, it might also show that some of the original stars were doubles.

I agree with this - only thing I'd add is that while extended objects (e.g. the sky background) are enlarged and therefore darkened by magnification, point sources (i.e. stars) are not enlarged (at least as long as the magnification is not too high) and therefore not dimmed: hence fainter stars become more visible as magnification increases, having greater contrast against the background, but the same thing doesn't happen with, e.g., galaxies, where the contrast remains the same.