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mrking
12-15-2007, 05:58 PM
As per Colorix request here is a little tutorial on how to adjust your photo to better represnt the values.

DISCLAIMER: There is tons to really know if you want a full colour corrected image. It is best you try to photograph your painting the best your can, especially if you tend to submit it to a competition or gallery. You can only work with what you have.

So, lets begin....
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1) This is the original image opened in photoshop. You can see in the histogram window to the right of the image how the graph does not come to the ends. This means the image is not utalizing the full range from dark to lights. Left side of histogram represents the 'darks' and right side represents 'lights'.

http://www.wetcanvas.com/Community/images/15-Dec-2007/108995-01.jpg


2) Now, before we progress it is always a good idea to make a copy of your current layer, just in case you want to go back to the original image.

http://www.wetcanvas.com/Community/images/15-Dec-2007/108995-02.jpg


3) Next we bring up the 'Levels' dialog box by pressing CTRL+L (PC). As you can see the data in 'Levels' represents the histogram data.

On the left and right side you can see the gaps. We need to close that gap.

http://www.wetcanvas.com/Community/images/15-Dec-2007/108995-03.jpg


4) To close the gap you move each corresponding slider over until it comes into the main mountain peaks. No need to touch the middle slider. After moving the slider over you can press OK.

http://www.wetcanvas.com/Community/images/15-Dec-2007/108995-04.jpg


5) Here is a comparison of the original and the corrected image.

http://www.wetcanvas.com/Community/images/15-Dec-2007/108995-05.jpg

Now, this is just a basic adjustment for those times when you need to do something fast to make sure people get a sense of what the values are.

If your image colours seem wrong and the histogram graph fills the window from edge to edge, then you have to start getting into the 'curves' aspect of photoshop or just reshoot your painting. :D

I hope this was of use to some.

Michael

Donna T
12-15-2007, 06:03 PM
Thanks Michael, that is very much appreciated! It's so frustrating to take the best picture I can only to have it look washed out when I post it. I will certainly give this a try.

Donna T

Colorix
12-15-2007, 06:23 PM
Thank you so much! This really makes a difference! Now that 'loudness' I felt is much more evident! I'll practice this, and I guess next step would be colour adjustment.... (hint, hint)

I'm really grateful, it is so silly to have PS and only know how to use the thingy that changes a pic into grayscale...

I'm gonna rate this, thank you so much!

PaulaT
12-15-2007, 07:39 PM
I am so great full to both you and Mandy, for posting these photoshop tutorials. If they had any classes near me I would take them but they dont. By the looks of it some of us have it and don't really know how to use it.So another huge thanks here.
Paula

Deborah Secor
12-15-2007, 07:42 PM
Mike. let me understand this better. All you're saying is that the black and white (far left and far right) sliders need to be moved to where the slope of the graphic begins? Why? What does that do? Sorry--inveterate questioner, I know, but what is the reason for this?

In Elements it's under Enhance, Adjust Brightness/Contrast, then Levels, where I find the histogram. What does the middle slider do? I've been known to slide it to lighten or darken an image so that I can see the details in those areas, so I know how to use it, but what is it's 'real' function?

Thanks...

Deborah

DAK723
12-15-2007, 09:28 PM
In Elements it's under Enhance, Adjust Brightness/Contrast, then Levels, where I find the histogram. What does the middle slider do? I've been known to slide it to lighten or darken an image so that I can see the details in those areas, so I know how to use it, but what is it's 'real' function?

Thanks...

Deborah

I use Corel Paint Shop Pro, but I believe it is very similar to Photoshop. The middle slider adjusts the "Gamma" which is a fancy word for lightening or darkening an image. So that is it's real function. I might add that it depends a lot on your camera - I need to adjust the gamma to lighten every picture of my artwork that I take.

Don

DAK723
12-15-2007, 10:20 PM
Here are a couple links that tell us more about histograms. One word of caution; if your photo does not have very light /white values or really dark/black values, the histogram will have a flat area at either or both ends. Pulling the histogram all the way to both or either edge may exaggerate the value range that you actually have.

http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml

http://www.sphoto.com/techinfo/histograms/histograms3.htm

Don

mrking
12-15-2007, 10:44 PM
Mike. let me understand this better. All you're saying is that the black and white (far left and far right) sliders need to be moved to where the slope of the graphic begins? Why? What does that do? Sorry--inveterate questioner, I know, but what is the reason for this?

In Elements it's under Enhance, Adjust Brightness/Contrast, then Levels, where I find the histogram. What does the middle slider do? I've been known to slide it to lighten or darken an image so that I can see the details in those areas, so I know how to use it, but what is it's 'real' function?

Thanks...

Deborah
Basically the histogram represents all the darks to lights in the photo.

Left = Darkest
Middle = Middle Tones
Right = Highlights

The best place to make sure the histogram is full to either side is on the camera itself. Many decent to excellent digital cameras will allow you to look at the histogram while adjusting. Digital SLR is best of course but even some poiint and shoot camera have them. If the histogram looks good on camera it will produce the best shot.

Now for the rest of us that is not always an option. You get an image that is a little washed out or too dark we need to adjust it.

Adjusting the middle slider is OK but that also changes the value of a lot of the middle values, which you don't want to do. The idea is to bring out the highlights and the darks without altering the rest of the image all that much.

Sometimes it is both sides, sometimes is it just one. Either way, adjust it so the histogram fills the area and select ok. Then you can go back into levels a second time and move the middle slider if need be.

I prefer the 'curves' function but that is a different ballgame.

For quick and dirty adjustments the 'levels' function works good.

The links below have some good info on it recarding levels and curves and many other technical tutorials as well.

Levels (http://www.cambridgeincolour.com/tutorials/levels.htm)
Curves (http://www.cambridgeincolour.com/tutorials/photoshop-curves.htm)
Image Histograms (http://www.cambridgeincolour.com/tutorials/histograms1.htm)

So much to know.... :D

mrking
12-15-2007, 11:51 PM
If anyone has some photos with some colour cast on them (photo looks blue-ish, red-ish or green-ish) could I get one for another tutorial on colour correction with curves. PM me. :thumbsup::thumbsup:

PeggyB
12-16-2007, 02:22 PM
I just got Photoshop Elements 6, and after having had only Photoshop Business Delux that was bundled with the computer when we got it eons ago, I realize I will now have to take a course at the community college to be able to fully utilize the program! I'm looking forward to it though...

In the meantime, thanks for the tutorial Michael. I'm goit to go play with some of my photos to see if I can improve them.

Peggy

*Marina*
12-16-2007, 03:11 PM
I am in the same boat Peggy and bought an online tutorial, only in Dutch though.

sundiver
12-17-2007, 05:18 PM
This is good- thanks!
What do we do if there is too much, contrast? That can happen when taking ref pics- the highlights are bleached out. Anything we can do with the histogram?

mrking
12-17-2007, 05:45 PM
This is good- thanks!
What do we do if there is too much, contrast? That can happen when taking ref pics- the highlights are bleached out. Anything we can do with the histogram?
Can you post an example? I ask, because if something is blown out there is little hope of getting anything back, regardless of what the TV shows tell ya. :D

If it is darker there is a very good chance you can see into the blacks.

Colorix
12-18-2007, 11:30 AM
Michael, and Don, thank you so much.

Been trying it out, and following links, and it works! Well, once I figured out how to open the 'levels dialogue box'... as the quick control L thingy didn't work. Had to find it in the tools. Learned a lot I wasn't looking for, though. Now I have been given a thread to start unravel the arcane mysteries of PS, and some fine links to learn from. Again, thank you so much.