problem subsetting MODIS 0.25 km data

[kbedka1]

See attached images, I'm trying to visualize some MODIS 0.25 km resolution visible data (i.e. MYD02QKM HDF files). You'll see in my screenshot of the Field Selector window that I subsetted about 40% of the granule with my green box. In my display window screenshot, you'll see that only a few lines of the requested region appears. If I make by subset box a bit smaller (not shown), then everything works fine. I recall Tom Rink saying that one cannot request a a full granule of 0.25 km data as this would require too much memory. But my computer has 16 Gb of RAM and I've requested less than half of the granule. This problem will happen with any 0.25 km file...this case does not cause unique behavior that others do not.

[bobc]

Hi Kris -

Thanks for the bug report. I tried this out on my Windows 7 machine with version 1.3 and a recent nightly build and I am having trouble replicating your problem. I can display the data without any problems regardless of the size of the region I subset. We also ran a test on a Mac and couldn't replicate your problem there, either.

Two questions:
1. What platform are you on?
2. What McV version and build date are you using?

Thanks -
Bob Carp

[kbedka1]

Are you using MODIS 0.25 km data? I am on a Mac OS X 10.7.5. I am using a nightly build 1.4 beta2 from 2013-09-12.

[bobc]

Hi Kris -

Yes, I've been doing testing with quarter kilometer MODIS data. I was testing with 2013 data, but I saw your image was from 2008 so I tried an older file and that worked for me as well. Here are the names of a couple files that I have tested with:

MYD02QKM.A2008235.0505.005.2009322195115.hdf
MYD02QKM.A2013152.0010.005.2013152170547.hdf

I have tried going through the Satellite>HYDRA chooser as well as the General>Files/Directories chooser with similar results. I've attached two images showing some of my testing with the subsetting of a region in the Field Selector and the display that was created.

I'll keep plugging away with more testing to see if I can replicate your problem. Are you using the General>Files/Directories chooser to load your data? Also, can you please send us your mcidasv.log file for us to take a look at?

Thanks again -
Bob

[kbedka1]

Thank you for looking into this. Yes I am using the General>Files/Directories chooser. I just tried the Satellite>HYDRA chooser and I ran into the same problem in that only a couple scanlines of data is display when I try to subset ~50% of the image. I have found that the Hydra Multispectral data has been very buggy in general...I'm also having problems with MODIS 1 km data. See the attached log file which shows the numerous errors I encountered yesterday afternoon with Multispectral Display. The bad 0.25 km display that I just created this morning does not seem to be considered "log-worthy" though...I don't see any timestamps from this morning in the log file.

[tdrink]

Kris,

This could be related to a known issue with swaths over the dateline. If you post the
specific files in this thread, I will try to verify.

Tom

[kbedka1]

I have put the following file on SSEC's ftp server:

pub/incoming/MYD02QKM.A2008286.1845.005.2009325222330.hdf

See attached for the region I tried to subset and the resulting display. This scene definitely does not cross the dateline, yet the display problem remains

BTW, why is there always an '_' beneath Reflective_Bands when MODIS 250m data is loaded? I could foresee this being confusing to a new user.

[tdrink]

I had no problem. Try using a smaller region, perhaps your system is having trouble
with image that size?

[kbedka1]

I updated to the latest nightly build, same problem. I have a brand new MacBook Pro, 16 Gb of RAM so I'd hope that my machine isn't inadequate enough to fail to display this data. Could something be wrong with my java, making it incompatible with the latest version of Mc-V? How would I diagnose this?

[tdrink]

Do you have Nvidia or ATI graphics?