[ptx] enblend levels

[J. Schneider]

Hello,
I've got a question concerning the use and function of the levels (-l) 
parameter for enblend.
I am working on WinXP with hugin 0.5beta3 and enblend 2.2

I wondered, why enblend didn't manage to do it's usual magic on a small 
panorama with huge lightness differences. I set the levels parameter in 
hugin preferences. Results didn't differ because it always used the same 
6 levels.

with hugin:
-v -w -s -z -l 3
	-> using 6 blending levels -> fairly bad result

-v -w -s -z -l 20
	-> using 6 blending levels -> same result

Then I put the multiple tiffs "directly" into enblend. (Or rather via a 
batch file in the sent to menu)

directly:
"<program path>\enblend.exe" -v -l %LEVELS% -o %PATH% %FILES%

-l 3	-> using 3 blending levels -> bad result
-l 20	-> using 8 blending levels -> relatively good result

So my questions are:
- How does enblend determine the number of levels it actually uses?
   Seemingly never more than specified, but sometimes/usually less.
- How does it take it's parameters from hugin? (It seems to ignore this
   particular setting when it is set in hugin)
- BTW: It seemed to me that there is no difference between -l<number>
   and -l <number> (with and without space). Right?

Results and source images can be seen at:
http://joachim-schneider.medianet-world.de/leveltest/leveltest.html


Joachim