> From a.cidadao@netcabo.pt Sat Jan 10 07:30 MST 2004 Subject: RE: Methane and broaband-IR Jupiter data Date: Sat, 10 Jan 2004 14:30:15 -0000 From: "a.cidadao" Hi again Mark, > >I now have a 14" telescope, two broadband IR filters (beginning >> transmission at 700 and 830nm), and two methane band filters (both CW > >at 889nm but with different FWHM - 5nm and 18nm ; I can send the >> transmission curves if needed). >Great, please send them. Here are the filter scans, with superimposed Jovian albedo and methane absorption coefficient taken from the literature. Also attached representative images obtained with both filters, depicting the diferences obtained. Ratio images (not attached) highlight these differences between the two "strong" methane filters, specifically on polar and EZ haze, and particularly over the NTB, curreently faded in the visible and broadband IR. Obviously, this was done with preprocessed images only (bias, dark and flat). I'm continue to collect data on another issue, specifically comparing carfully registered methane band and broadband IR images. There is evidence of some (only some) SEB methane-bright rifts that correspond to broadband-IR SEB dark areas and vice versa. Can send the images if you want. If you are aware of relevant literature references on comparative analysis on two different "strong" CH4 filters (differing on FWHM), namely to probe different levels of the "upper atmosphere" pleas let me know. I guess there is available more info on ratios between weak methane and flanking continuum than on that. Best Antonio > From a.cidadao@netcabo.pt Sat Jan 10 07:48 MST 2004 Subject: RE: Methane and broaband-IR Jupiter data Date: Sat, 10 Jan 2004 14:48:11 -0000 From: "a.cidadao" Hi again, >> I have started to make image-ratios between the two methane filters >>(with images only corrected for bias, dark and flat obviously). I can >>send you the results, which I do find interesting. >We tend towards images more than ratios. OK, this is the only image depicting ratios that I'm sending, not for posting on the site but only for you to give me your opinion, please. Notice the differences in polar and EZ hazes, showing minor differences in NEBs projections, but mostly the differences in NTB. Best Antonio