these three are greatly reduced in size.
Here is an example of stacking to improve detail by shooting pictures with different exposure settings not focus settings
Chris Broadhurst took these three pictures at -1, normal and +1 EV settings
these three are greatly reduced in size.
The window area in the first and last pictures
Notice the masonary is visible in the first picture and the stained glass
window in the last. The problem now is to combine all three
pictures in such a way as to show maximum detail.
To process this stack I have modified the standard Do Stack macro. Note if you do anything like this you can restore the original macro by clicking on 'Restore Standard Macros' at the top of the Macro menu.
Either download the macro set above and save it in the same place as CombineZM.exe, then Load Macro Set from within CZM or follow the instructions below to modify the existing macro.
To modify a Macro click on Macro->Edit->Macros as shown below
Now choose the macro to edit, 'Do Stack' in this case
Working down this macro, we do not want to alter the colour or brightness of any frame, so click on the 'Balance Colour and Brightness' line to highlight it as above, now click the 'Delete' button on the right of this dialog box and the highlighted line should disappear.
Now we do need to align all frames but a better function would be the single pass version, to make sure it's done right we will apply it twice. Highlight 'Align All Frames Automatically (Two Pass), now go to the 'Command' dropdown list below and locate 'Align All Frames Automatically (Single Pass)', click on it and then on the 'Update' button above to the right, this will replace the two pass version of align with the single pass version. To include a second alignment step highlight the align all frames line again, click the 'Edit' button and this line will be copied down below, now click on the 'Insert Above' button and a new copy will be placed above the original.
By trial and error (using a combination of depthmap and find detail see below) I found that 'Find Detail(25)' was too sensative it included a lot of false detail in the Picture, and also that 'Find Detail(100)' did a better job so we must edit this line. Highlight it and click on 'Edit' alter the value '25' in the box below to '100' and click on 'Update'.
In a similar way change 'Remove Islands(5}' to 'Remove Islands(25}', we do not anticipate there being any really small patches in the result so we can drop them if the appear.
Now there are a lot of lines at the bottom of the box we don't need, so delete them one at a time by highlighting one and then clicking on 'Delete' as before.
Before clicking on 'OK' make sure the macro editor dialog looks like this
Now click on 'OK' then close the choose dialog box. If you wish save your edited macro set using 'Save Macro Set As' which appears in the menu illustrated above, you will then be able to reload it when you wish using Mocro->Load Macro Set.
Now assuming the pictures to stack have been loaded click on 'Do Stack' or
'Stack Exposures' on the Macro Menu and they should be processed with the
following result
There are some problem areas in this picture, you could edit them out with a paint program, but here is how to do it in CZ
When keys are mentioned below to invoke functions there is usually an equivalent menu item on the View menu.
One bad area is up at the top right, there is a small dark circle, here is a
'depthmap' for this picture you can see the area in question as a blue
blob. the darker blue colours correspond to the areas of the
picture that came from the lowest frame in the stack. The lighter
greenish areas come from the top of the stack. The inbitween shades
come from intermediate frames. Notice the colour does not change in
abrupt steps, in this example there are not just three shades corresponding to
the three frames..
The 'Interpolated Output' function at the bottom of the Stack menu uses these
intermediate values, if a depthmap value lies between two frames it is
interpreted as a mixture of these two frames by this function, thus there is no
abrupt change between frames
This may be enough to hide the blemish, but not in this case.
To get a view of the Picture press 'tab'. CZ has two areas in which outputs from operations are displayed, the first is called the 'Picture' and the second the 'Output' buffer. The Picture buffer can only be filled in one way, by interpreting the 'Depth Map' this is a third buffer containing numbers which indicate which frame each pixel in the Picture should come from, you can visualize this by pressing 'D' as explained above.
The second buffer Out receives the result of most other operations on the Picture, one or more Frames or the DFT output buffer. As an example 'Interpolated Output' mentioned above takes the Picture (Depthmap) as input and outputs to Out.
To switch between a view of the Picture and the Active Frame and back press 'TAB'.
To switch between a view of Out and the Active Frame and back, press 'O'.
All of this might sound complicated at first, but becomes easy with practice.
Drag a small box around the area of interest using the mouse, point at one
corner of the desired box, press and hold the Left Mouse Button down while
moving the pointer to the diagonally opposite corner of the desired
area. Now release the left mouse button and a box should be visible
around the area. Next press the Right mouse button once and the
area will be enlarged (repeated right clicks cycle through various view
options)
Notice the three bright spots, they are not the tracks of some ghostly
aparition, but some sort of camera artifact, maybe a reflection in the lens or
a 'hot spot' on the CCD device. There is really only one spot but
due to a small camera movement, and the need to realign the three frames the
dot appears in a different place in each frame. CZ thinks this spot
is valid detail and includes it in the Picture.
Press 'P' and the display enters 'Plane Mode', 'P' will switch back to normal
view as well. Plane mode shows you the contribution made to the
Picture by each frame, use the Up and Down arrows to view each Plane.
In the last plane the included area is nearly all black, to see it more clearly
press 'Space' which turns empty pixels white to aleviate this problem.
Leave the top Plane alone, on the second and third press the 'Delete' key, this
will clear these planes. Now press 'P' once more to return to
normal view.
Notice the hole where the circle from the bottom and the anulus from the middle
frames have been removed.
Now we need to fill this hole, click on the Stack->Fill Gaps menu item
There are many other ways to edit the Picture in CZ but this should give you an idea of how things link together.
The full sized picture so far, I used Interpolated Output as mentioned above and
saved Out and not the Picture.
There is still room for improvement in this picture especially in the lighter
areas at the mid right.