photo sharing and upload picture albums photo forums search pictures popular photos photography help login
Samir Kharusi | all galleries >> Galleries >> Sizing Planetary Images To Compare vs The Theoretical Limits For Your OTA > Mars_C8_C14_Nyquist_Sizes
previous | next
Samir Kharusi


During the 2003 close opposition of Mars there was a lot of talk regarding atmospheric dispersion on Earth introducing a blue limb to images of Mars. The blue edge is of course not seen in the JPL-NASA simulations. But Lo and Behold! The HST image of Mars also shows that blue edge towards the north (top). It's all to do with Mars itself, not refractive dispersion in our atmosphere! From the above examples I'd say that the C8 has done a better job of approaching its limits than the C14, a nice endorsement about Nyquist-display as a fairer way of judging images from smaller OTAs than simply blowing them up large to some random size. Larger OTAs are of course clobbered by seeing relatively more often than smaller OTAs. The larger OTAs routinely show more detail, but also they routinely fall further short of what is theoretically achievable than the smaller ones.

Now let us look at what is in store for us in the forthcoming oppositions for Mars, Jupiter and Saturn, next...

other sizes: small medium original auto
comment | share