Re: [Usability] inability to experiment

["David Dolphin" <David Dolphin skynet ie>]

The first version of Photoshop I learnt to use was CS2 but I've taken
a look at older versions (5&7) since then and seen some changes. Even
though I know the features available in Photoshop CS2 (or CS3) were
not all implemented at the same time I feel that they compliment each
other.

Photoshop's undo system is incredibly useful. It is closely tied to a
history of applied commands and can be compared in ways to a simple
revision control system.

Say you make 10 edits to a photo (touching up blemishes, removing red
eye, whitening teeth, improving colour balance, applying a photo
filter), rev0 to rev9. Just after you've done rev9 tapping Ctrl-Z
(using default key bindings) will toggle between rev9 and rev8, just
back and forth. this may be useful to see if the filter you applied
had the desired effect or not.

Say you need to apply several filters to gain the desired effect.
These filters are rev6 to rev9. Tap Crtl-Alt-Z a few times to bring
you back to rev6 and then tap Crtl-Z to cycle between rev6 and rev9.
This way you can see if multiple filters were effective.

Even within a single revision there may be multiple tweaks. I think
this is related most closely to Matthews original comment. Say I want
to adjust the Brightness/Contrast of an image [1]. Hit "Image -->
Adjustments --> Brightness/Contrast" and a simple window will pop up
with two sliders, two buttons, a checkbox and two text input boxes
(Example: http://url.ie/epa ). It looks relatively straight forward
but there are a few important hidden features.

1) There are three ways to set the value of the Brightness or
contrast. You can scrub the slider to the desired value, you can enter
an exact text value or you can scrub the "Brightness" text. Only when
scrubbing the brightness text can you use the Shift and Alt modifiers
to increase/decrease the amount of points altered per pixel of mouse
movement. If you scrub "Brightness" 7 pixels to the left the value
decreases by 7 units (in this case, and in most cases, percent). If
you hold Shift and scrub 3 pixels to the left the value decreases by
30 units and if you hold Alt and scrub 53 pixels to the right the
value will increase by 5.3 units.

2) If you hold Alt the cancel button changes to a reset button.
Whenever you open the Brightness/Contrast pop-up window you are
starting a new revision. When you hit OK you have just finished that
revision. As such the Brightness/Contrast window (when opened in this
way) will always start with values of 0 and 0 (at the start of a
revision the brightness has not increased or decreased, that is the
point of the revision, to increase or decrease this option). Tapping
cancel will dismiss the window and not apply the revision. Hitting
reset will bring the values of Brightness and Contrast back to 0 and
0, the default values for that pop-up window/dialogue box.

Lets say you have created an adjustment layer [2] to modify
brightness/contrast. You save the adjustment layer with values of 80
and -41. When you reopen the adjustment layer to edit these values you
can reset the values to 0 and 0 if you want to start from scratch. Now
if you dislike the changes you have made the second time around and
decide that the first edit of 80 and -41 was better, just tap cancel
and the values will return to the values that existed when the box was
opened.

So to sum up, in Photoshop dialogue boxes: cancel will returned the
values to whatever was defined by the user before the box was opened
(and perhaps a system value if the user had never entered a value);
reset returns the values to a system defined preset.

Kind Regards,


David Dolphin

[1] Yes, I know I'd prefer to use a combination of Levels, Curves,
Hue/Saturation, Shadow/Hilight and Variations, preferably using
adjustment layers so I can alter the values later and play with
opacities, blending options, vector masks, layer masks and all that
other fun stuff, but some people like Brightness/Contrast. Don't ask.

[2] Layers can be thought of like sheets of acetate. An adjustment
layer is a way to apply an effect or edit to a layer without modifying
that layer. If you place a brightness/contrast adjustment layer over
an image layer you can toggle the adjustment layer on and off to see
what effect it has had. One of the most important aspects of
adjustment layers is that you can edit the values of adjustment layers
at any point after you have created the layer, something that is
almost impossible with a linear history based system.

2008/5/27 Matthew Paul Thomas <mpt myrealbox com>:
> This reminds me of Photoshop, which has accumulated multiple
> partly-independent Undo/Redo/Repeat functions for different types of
> action. As far as I can tell without actually having a copy: :-)
> *   "Edit" > "Undo {whatever}" undoes/redoes the most recent action;
> *   "Edit" > "Step Forward" and "Step Backward" act like "Redo" and
>    "Undo" do in normal programs;
> *   "Edit" > "Fade..." alters the opacity of the most recent action
>    (something which only really makes sense for a bitmap editor);
> *   "Select" > "Deselect" and "Reselect" undoes and redoes the most
>    recent selection;
> *   "Filter" > "Last Filter" repeats the most recent filter on the
>    current selection.
>
> > Then there's the question of whether a 'Reset to Defaults' button
> > would be useful too... probably 'yes', in some cases, but things would
> > start getting awfully cluttered if you add a Defaults and a Revert/
> > Undo to every Preferences dialog...
> >...
>
> "Undo", "Revert", "restore from backup", and "Reset to Defaults" (where
> relevant) are steps on a continuum that really should be simplified someday.
>
> Cheers
> --
> Matthew Paul Thomas
> http://mpt.net.nz/
> _______________________________________________
> Usability mailing list
> Usability gnome org
> http://mail.gnome.org/mailman/listinfo/usability
>



--
http://pf.skynet.ie/ - Penguin Friendly
President, University of Limerick Computer Society
"Early to rise and early to bed, makes a man healthy,
but socially dead" -- Animaniacs