Frequently Asked Questions

1) Does Resomask™ improve the resolution of refractor (and other unobstructed) telescopes?

Yes. Resolution refers to the ability to "separate" two closely-spaced points of light (for example, a close double star). There have been many definitions of resolution proposed (Rayleigh, Dawes, Sparrow, etc.), all indicating improved resolution with a reduction in the size of the central spot (Airy disk). Since Resomask™ reduces the size of the Airy disk (while increasing the intensity in the surrounding rings, see FAQ #4 below) the resolution is improved.

2) Does the fact that the Resomask™ decreases the amount of light cause the resolution of double stars to improve?

Simply decreasing the amount of light in a telescope (as, for example, with an ND filter) does not change the resolution. However, fainter stars show a smaller size Airy disk visually than brighter ones due to the difficulty of the eye to see fainter objects. In other words, the outer part of the Airy disk is harder to see in fainter stars making the perceived Airy disk appear smaller than it does with brighter stars. In the case of Resomask™, however, it is the design of the mask that enables reduction of the physical size of the Airy disk (and not just the perceived size).

3) Can Resomask™ be used on double stars with unequal brightness?

Yes. Resomask™ can be used to aid in resolving closely-spaced unequal pairs that have a difference of 2.5 magnitudes or less. A double with a greater difference in magnitude may not be suitable for this device since the intensity of the rings is increased relative to an unobstructed telescope.

4) Can Resomask™ be used on the planets?

Resomask™ increases resolution on double stars by narrowing the Airy disk. A consequence of this reduction in the size of the Airy disk is that the ring structure around the disk has increased intensity. This results in a significant reduction in the contrast seen on extended objects (such as planets) for most of the range of available spatial frequencies. In other words, the visibility of most of the detail visible on planets is made considerably worse with Resomask™. However, for double stars the intensity in the outer rings does not compromise the ability of this device to improve the resolution of a closely-spaced pair.

If you have any questions that are not answered here, please contact us.