[GEMPAK #XYG-194160]: NEXR2RHI image artifacts - what am I doing wrong?

Greg,

The NEXR2RHI program is a Unidata addition to GEMPAK, authored by the developer 
who was here before me.  I checked RSL updates and for any CRAFT file format 
changes and found no leads.

However, I was able to control the off contouring with INTERP and CONTUR.   I 
recommend turning OFF interpolation and limiting contouring to 2 or less. I've 
been able to produce acceptable RHI plots with CONTUR = 0, 1 or 2, without the 
contouring artifacts.  Setting it to 3 or greater re-introduced the errors.

Please give this a try and let me know how it works for you.  It's not a 
solution which addressed the cause, only the symptom, but hopefully it works 
well enough for what you plan to show.  I'm sorry I don't have a better 
solution for you.

Michael



> Michael,
> Thanks for the quick update - much appreciated. I understand the meeting prep 
> and priority. I'll look forward to hearing more from you after the meeting.
> 
> Thanks!
> Greg
> 
> On Mar 30, 2012, at 2:16 PM, Unidata GEMPAK Support wrote:
> 
> > NAWIPS/GEMPAK developers at NCEP said they have seen something similar in 
> > GDCROSS before, when selecting a grid cross-section, and it was caused then 
> > by an over-filled array, so that's likely the case with NEXR2RHI.  
> > Unfortunately I won't be able to time on this until the middle of next 
> > week, so I'll try to get back to you Tues or Weds.  Sorry about the delay, 
> > we have a committee meeting on Monday and Tuesday which I'm swamped with at 
> > the moment.
> >
> > Michael
> >
> >
> >> Michael,
> >> Any progress on this issue yet? I have PIs who are counting on being able 
> >> to use a GEMPAK script to create these cross-sections for a field campaign 
> >> starting in a few weeks.
> >>
> >> Thanks,
> >> Greg
> >>
> >>
> >> On Mar 23, 2012, at 4:11 PM, Unidata GEMPAK Support wrote:
> >>
> >>> Yikes, that indeed does look awful.  I'm seeing the same artifacts and 
> >>> turning interpolation off (INTERP=n) doesn't remove them all.
> >>>
> >>> Will update you when I know more.
> >>>
> >>> -Michael
> >>>
> >>>
> >>>
> >>>
> >>>> I'm trying to plot x-sections from the NEXRAD Level II radars of 
> >>>> reflectivity and I'm getting a lot of artifacts in the image that render 
> >>>> the product useless. Attached is a screen shot I created from data from 
> >>>> yesterday from the KHTX radar in Huntsville. Below are the values I used 
> >>>> in NEXR2RHI to create this plot:
> >>>>
> >>>> GEMPAK-NEXR2RHI>l
> >>>> CXSTNS   = 34.75;-86.6>33.5;-86.8
> >>>> GVCORD   = hght
> >>>> PTYPE    = lin
> >>>> YAXIS    = 0/20000
> >>>> CINT     = 0
> >>>> SCALE    = 0
> >>>> LINE     = 1
> >>>> BORDER   = 1
> >>>> TITLE    = 1/-2/RHI Base Reflectivity Level II ^
> >>>> CLEAR    = YES
> >>>> DEVICE   = XW
> >>>> TEXT     = 1
> >>>> PANEL    = 0
> >>>> CLRBAR   = 1
> >>>> CONTUR   = 3/2
> >>>> FINT     = 4/4/64
> >>>> FLINE    = 0;30-7
> >>>> CTYPE    = f
> >>>> RADFIL   = /export/ldm/data/gempak/nexrad/craft/KHTX/KHTX_20120322_2103
> >>>> RADPARM  = dz
> >>>> RADTIM   = last
> >>>> INTERP   = y
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> I've tried different radars as well as different values (orientations) 
> >>>> for the cxstns parameter but most produce artifacts like those shown in 
> >>>> this image. What am I doing wrong?
> >>>>
> >>>> Thanks,
> >>>> Greg
> >>>>
> >>>> -----------------------------------------------------------
> >>>> Greg Stossmeister
> >>>> Head - Collaborative Tools and Metadata Group
> >>>> NCAR/Earth Observing Laboratory (EOL)
> >>>> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> >>>> e-mail: address@hidden
> >>>> Mailing Address:          Shipping Address:
> >>>> NCAR/EOL                    UCAR Foothills Lab 1
> >>>> P.O. Box 3000               3450 Mitchell Ln
> >>>> Boulder, CO 80307      Boulder, CO 80301
> >>>> ------------------------------------------------------------
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>>
> >>> Ticket Details
> >>> ===================
> >>> Ticket ID: XYG-194160
> >>> Department: Support GEMPAK
> >>> Priority: Normal
> >>> Status: Open
> >>>
> >>
> >> -----------------------------------------------------------
> >> Greg Stossmeister
> >> Head - Collaborative Tools and Metadata Group
> >> NCAR/Earth Observing Laboratory (EOL)
> >> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> >> e-mail: address@hidden
> >> Mailing Address:          Shipping Address:
> >> NCAR/EOL                    UCAR Foothills Lab 1
> >> P.O. Box 3000               3450 Mitchell Ln
> >> Boulder, CO 80307      Boulder, CO 80301
> >> ------------------------------------------------------------
> >>
> >>
> >>
> >>
> >>
> >>
> >
> > Ticket Details
> > ===================
> > Ticket ID: XYG-194160
> > Department: Support GEMPAK
> > Priority: High
> > Status: Open
> >
> 
> -----------------------------------------------------------
> Greg Stossmeister
> Head - Collaborative Tools and Metadata Group
> NCAR/Earth Observing Laboratory (EOL)
> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> e-mail: address@hidden
> Mailing Address:          Shipping Address:
> NCAR/EOL                    UCAR Foothills Lab 1
> P.O. Box 3000               3450 Mitchell Ln
> Boulder, CO 80307      Boulder, CO 80301
> ------------------------------------------------------------
> 
> 
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: XYG-194160
Department: Support GEMPAK
Priority: Urgent
Status: Open