A question about the histogram

[guggle (Michael)]

Hi everyone,

I'm using Photoshop CS 6 to process one of my photos and when I first load the TIFF I see the histogram look like 'histo1' below. After I do a bit of level and curves manipulation, the histogram looks like 'histo2' below.

My question is, what is the goal here? Should I be trying to make 1 spike out of the 3 or leave them as is and stretch as much as I can without clipping?

Cheers, Michael.

[cometcatcher (Kevin)]

Originally Posted by guggle

My question is, what is the goal here? Should I be trying to make 1 spike out of the 3?
Cheers, Michael.

Pretty much. If you can get them closer together to start with by camera white balance adjustment that helps also.

[tlgerdes (Trevor)]

This is when you start stretching each colour channel individually

[rustigsmed (Russell)]

i like to go individual, but if it gets a bit hairy try Auto Colour under image that tries to align the channels.

[jsmoraes (Jorge)]

with histogram you can first check the adjustment of background. All channels: red, green and blue must have similar values, and so, to be one over the other in the graphic.

Others information can be seen, e.g. distribution of one channel data, that can help you decide if this channel must be incremented ou reduced.

[guggle (Michael)]

Thank you everyone for your input - it's helping me understand processing astro photos greatly!