The dimSize shows that you created a 3 bands image.
That is not a problem as long as you treat each band(layer) individually.
What is the command you are using to export the image and what is the format you are exporting to?
It seems like you GeoRaster object and your tiff file are perfectly fine according to the way it was created. What happens if you change the "dimSize=(512,512*,3*)" to "dimSize=(512,512*,1*)" in your previous createTemplate call?
What you are seem is not an RGB image but a composition of 3 bands that looks like RGB. The data type is still 23 bit real as you mentioned. Right?
How are you visualizing that image? What software?
Yes, i use windows photo viewer/ oracle georaster viewer tool to view images. Also, the image does contain red, blue, green points. So, maybe it is using all the 3 bands. So, how can i use/display only 1 band.
If i use
'dimSize=(512,512,1) cellDepth=32BIT_REAL interleaving=BIP',
In your second command, you copied the "*" from my post. That is not part of the command. It supposed to turn the text into bold. Sorry for the misunderstanding.
My suggestion was for you to try to work with a single-band image. I don't know what are the other commands you have in your code but are you sure that the error message "invalid band and layer number" is coming from sdo_geor.createTemplate? You might have some code after that is still expecting the 3 bands and that is where the error is coming from.
So here is the summary:
If what you want to see is a "grayscale" image and your data type is 32BIT_REAL, there is no need to 3 bands. If you have to have 3 bands. You can use GeoRasterViewer and play with the option "View>Show Layer Mapping" or alt+p to select the band you want to see. If you want to see band 1, select "1" for Red, "1" for Green and "1" for Blue and click on "Refresh".
Photo viewers can only handle well unsigned 8 bit integer. I suspect. On GeoRasterView you might try the "Image" processing option to find the best representation of the cell values of that image.