We would mainly be using this tool with linear images which by their nature are very dark , the STF will stretch your image but only on your screen that means your data has not been altered and if you save your image now it will still be dark.So remember to disable the STF after you have finished with it.

We like to screen stretch our images because some processes need to be applied at the linear stage these would inc things like DBE . colour correction ,background neutralization and deconveloution etc so its nice to see what we are doing

When we open up the STF process below is displayed and if you select a image with your mouse and activate the real time view ( K )

its name will appear on the top bar

A ) This will lock the RGB channels together so sliding one will slide all three for ease

B) Will restore the zoom on the sliders back to the default scale of one

C) The automatic stretch , this is what I use the most one click stretch very handy - you can alter the default auto setting by holding ctrl and clicking on the autostretch Icon

D) Here you can manualy enter the STF setting , not something I have used

E) This is what you use to manually move the sliders , just left click hold on your mouse and slide away

F) The zoom tool , with high screen stretch's the midtones and shadow sliders can get very close so hold the plus cursor over the area you want to Zoom in and left click on your mouse for more detail . Notice here how the selected tools are surrounded a light col box

G) The zoom out tool use as above

H) The scroll , If you have zoomed in on the bar you may need to move it to see your desired location , hold down the left mouse button on the bar and drag to suit

I) Black / mid and white point readout

J) Clicking these icons will restore the selected channel to the default setting

K) A important one this clicking this will activate the real time view i.e. as you move the sliders the screen will show instant alterations these will change colour when active

L) Master reset , restores all to default

For most instances I do the following

1) select your image

2) Click on the A ( autostretch ) Labled C

3) do a fine adjust of the sliders if necessary

4) If your colour balance is not correct you can unlock the RGB channels ( A ) and then adjust each channel to taste

Another clever trick you can do is that do is that if you are happy with stretch that you have achieved with the STF you can transfer the settings to the histogram Transformation tool and make the setting permanent from there, to do this do the following

1) stretch to taste in STF

2) Activate the Histogram tool

3) Drag the new instance Icon to the bottom bar of the histogram Transformation tool ( The icon will have a square next to it when in correct place ) and release, the setting are now in the Histogram tool

4) Now disable or reset the STF

5) Apply the hisogram transformation tool to the image

There are also further Icons on the tool bar from where you can enable some of the above , you might do this because you can close the STF menu down and the settings will still apply

Also under- Image-screen transfer Functions there are further settings

Lastly I will say again STF alterations are only on your screen , disable when

finished permanent alterations will be done with the histogram Transformation