Printing and Gamma correction

Question

I read somewhere in the aperture manuals to match the monitors gamma in prints you may need to set gamma correction to 1.1 or 1.2 in the print dialog.
If I am exporting prints to a pro photo lab am I likely to need to correct the gamma of the exported image or should I send it uncorrected?
Also, should I generally have black point compensation on or off?

Answer 1

I've this code :
short[] threshold = new short[256];
for (int i = threshold_level; i < 256; i++) 
   threshold[i] = (short) i;
BufferedImage dest = new BufferedImage(source.getWidth(),source.getHeight(),source.getType());
LookupTable look = new ShortLookupTable(0,threshold);
BufferedImageOp buff = new LookupOp(look,null);
buff.filter(src, dest);but I don't know what it's really change, if it's the input level of the BufferedImage, the gamma, the twice...
So to compare I used a commercial Software and I seen that my result is corresponding to a change of the input level of my BufferedImage and a gamma correction too. But i just want to change the input level of my BufferedImage, but I don't find example wich does that, so I try to make a gamma correction in the aim of cancel the first gamma correction produce by my LookupTable.
I hope you understand me. The aim is to make an histogram modification of a BufferedImage.
thank you