Parts of raster disappear

[WilliamIsaacs]

Howdy,

Set up:

I have created a raster mosaic in ArcGIS 10.2.2 of georeferenced  .tif aerial photographs. size is about 9.5 Gigs uncompressed, and the tif's are 1 band,16 bit that I converted from MrSIDs in ArcMap. I have defined and built overviews, created pyramids and stats, seamlines and blended along the seamline for mosaic method. This is everything that I normally do to make a Raster Mosaic in a fgdb and never had this issue before.

so here is my question:

When I'm at full extent the image is fine, as I zoom in parts of the raster disappear(not checkerboard-ing just white background) and as I move the image different parts with appear or disappear. The pattern changes depending on which mosaicking method I select. I have found a work around but I would rather not lose any data by exporting the mosaic as new raster. Any suggestions or possible solutions?

Thanks

Will

[SamuelTompsett]

Hello William,

Could you be more specific on the level of pyramids you have built? Typically when zooming in, if a raster disappears at certain scales, it is a sign something is going on with the pyramids.

Could be other things as well, but best to start with the number of pyramid levels.

Hopefully that helps!

Sam

[WilliamIsaacs]

I left it default but it should be a full set of pyramids per the tool help

[SepheFox]

Hi William, I had a similar problem, and it was indeed the pyramids. Maybe you could try rebuilding them? For what it's worth, this problem didn't affect any analysis, but was just visual. That's not helpful if you're needing them for display though.

[WilliamIsaacs]

i have rebuilt the pyramids in two different mosaics and the issue is still the same. it is just these two that are giving me issues. I got word that it might be "Maximum number per mosaic" setting and upped that from 20 to 50 to no avail.

[JeffreySwain]

What bit depth were the original tifs?  Since they are 1 band I assume they were not 16 bit originally?  I think that the issue is probably with the bit depth being up converted.  I would consider establishing a NoData value and not promoting the value.  What you described used to be common with 1 bit data that would be upconverted and then in the pyramids the data would be lost.  Overviews by default are 8 bit, and that promotion can be problematic.  So I would consider the original conversion and not promote them from 1 bit. 

[WilliamIsaacs]

They were originally 1 band 8 bit mrSID's, the reason i converted to tif was because the SID's were doing the same thing, and i thought that maybe it was the source of the SID's being picky about conversion and such. Ill give it a try and let you know.

[WilliamIsaacs]

Thank you for your help in this issue

[WilliamIsaacs]

Thanks for all the help guys. I decided that I wasn't losing enough resolution by exporting the mosaic to new raster and then put that raster into a new mosaic that it was worth pushing further. 

[GabrielUpchurch1]

Hi Will,

Glad to see you found an approach that works.  Just curious, was there any overlap between the source images (or their footprints) or were they rotated tiles?