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Hi Mike, First, I want to correct a brain freeze in my last email! I said: > > I am using the GRB-delivered GOES-16 imagery for "production" as the GRB > > Full Disk image resolutions are actually less (worse) than the sectors that > > have been in the UNIWISC feed for many years. I meant to say (but my fingers betrayed me by typing something different): I am using the GRB-delivered GOES-16 imagery for "production" as the NOAAPort Full Disk image resolutions are actually less (worse) than the sectors that have been in the UNIWISC feed for many years. The comparison is the GOES-East sectors from GVAR were 4 km resolution, and the NOAAPort-delivered (SCMI) Full Disk sectors are 6 km resolution. So, IMGREMAPing a lower resolution image into a higher resolution output template will result in feature smearing. Sorry for the mis-infomation!! re: GIS "layers"? > I apologize, I'm using the wrong terminology. No, I'm talking about > McIDAS-X. Example: MAP FILE=OUTUSINT is what we typically use to plot > interstates, including I-355. Map files like these is what I was referring > to. OK. I think that I am the one that added US Interstate maps to McIDAS (a LONG time ago, hence the fogginess), so I guess that it is up to me to find a current map database from which I can create a new McIDAS interstate map file. re: > Got it. This isn't a big concern, more of a passing curiosity we ask > ourselves from time to time. OK. re: > Okay, I'm sorry, but I have one other question for you. Some of the RGB > products we'd like to make have recipes which include a Gamma element to > one or more of the RGB channels. While I've figured out how to do > differences and scaling using IMGOPER, could you tell me how I could apply > a Gamma correction? For reference, I'm using documents like this and > others: http://www.eumetrain.org/RGBguide/recipes/recipes.pdf As far as I know, McIDAS has no facility for applying a Gamma correction. By the way, Fred Mosher wrote code to create pseudo-true color images in McIDAS using a combination of Channels 1, 2 and 3 for Embry-Riddle Aeronautical University (ERAU). Here is a snippit from what he wrote in describing this to me: "During the day, 3 visible channels are combined into a true color image. The green channel is generated by a weighted average ( .29 .29 and .33) for bands 1, 2 & 3. The red & green channels are brightness normalized, and the blue channel also has a Rayleigh scattering correction in addition to the brightness normalization." The URL for the ERAU satellite web pages is: http://wx.erau.edu/erau_sat/ There is some _very_ nice work shown in their site! Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: JGN-249914 Department: Support McIDAS Priority: Normal Status: Closed =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.