What are the advantages of publishing a set of imagery as a mosaic data set versus. a cached imagery service in terms of availability, resource consumption?
If you transfer some imagery to a mosaic data is it sensible to expect a performance upgrade (less crashes, availability issues from remote sites)?
Is that to broad of a question to get specific answer on?
One obvious advantage of publishing an image service directly from a #mosaic datset (assuming you have Image extension) is that you can add data to the mosaic and see the results immediately reflected in your service. The alternative, creating an image cache, is time intensive and can consume really significant disk space, depending on your caching levels.
Hey Robert,
publishing a cache vs. a dynamic image service from a MosaicDataset is a very good and valid question. Here a few thoughts/facts:
CACHE:
Pre-generated, tiled dataset, limited to 8bit depth of data. Usually for visualization purposes only. Pre-defined scales.
MOSAIC DATASET as IMAGE SERVICE:
Dynamic (see additional comment (*) below!) access to imagery collection applying on-the-fly processing template(s). Any sale, selection, rule can be defined.
So it is all about what you need/want to offer and the trade-off between flexibility and 'un-burdening' the server to do CPU work.
(*) Please note: There is a combination of both: Mosaic Datasets can cache process chains results so that any query after the first one asking for a result is 'cheaper' ... and you can define a cache on the ImageService that will be used similar to a cache, whenever the ImageServer is called with default properties ... and only when settings for a query change (different output compression, attribute query, mosaic method, ...) a new Image will be generated.
Hope this helps. Feel free to ask for clarifications if this is not answering it.
Guenter
Thanks for the replies back on this. It sounds like mosaic data set have a great deal of advantages over other options. I'll share those thoughts with colleague here. Another thing I am running into is the need to clip or remove a set of three banded rasters 255, 255, 255 values from the underlying raster. so they can be Mosaic together That will be done thru either con statement to remove them or converting the SIDs to a file format that can iterated thru in List Rasters to clip them to a shapefile grid from existing script. Probably I'll have to explore the options of the mosaic tab as well.