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			New UH8K observing utilities
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All these new commands have to be entered at the prompt on a neptune window.
(pop up the Hosts menu by clicking on the right button in the screen
background, and then go to `Summit HPs', then release the button when being
on `neptune'). Having this neptune window on the right screen (control is 
on the center one, display on the left one) will make the whole setup easy 
to visualize.

A - Automatic focus sequence
B - Setting the Z prime focus bonnette
C - Offsetting the telescope
D - Photometric standards script
E - Shift-and-Add script
F - Dark exposures script (reminder)

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A - Automatic focus sequence
----------------------------

This is a very simple script to use that will take the whole uh8k
focus sequence for you, including telescope offsets and Z bonnette
motions. You still have to load the image and analyze it yourself
to find out the best focus, something pretty simple using Skycat.
A more complete sequence including proposing the best choice to the 
observer will come soon.

When typed without any argument, the `uh8kfocus' command displays this message :
usage: 'uh8kfocus itime zcenter nframes deltaz'
       takes 'nframes' exposures of 'itime' seconds
       moving the Z of 'deltaz' and offsetting the
       telescope 5'' North between exposures.
       The sequence is centered on Z = 'zcenter'

Example : uh8kfocus  10 0.6 7 0.05
(0.1 is actually small enough for the delta Z)

Will show during execution :
	==========================================================
	Focus exposure - Exposure time : 10 sec
	----------------------------------------------------------
	Exposure 1 : Z = 0.445
	Exposure 2 : Z = 0.496
	Exposure 3 : Z = 0.547
	Exposure 4 : Z = 0.598
	Exposure 5 : Z = 0.648
	Exposure 6 : Z = 0.695
	Exposure 7 : Z = 0.738
	----------------------------------------------------------
	Moving telescope back to initial position...
	----------------------------------------------------------
	Reading out detector...
	focus completed, check your image with Skycat - Pick Object.
	exposure 1 is up
	exposure 7 is down - double offset
	==========================================================

Then load the image in Skycat and use Pick Object to check the FWHM.
As noted, the sequence of images will extend from the top towards the 
bottom of the image. The last double offset makes the last exposure easy
to recognize. The filename will have a "x1.fits" extension.
Use the pfocus command (see below) to set the best Z value.

As a starting point (beginning of the run), use steps of 0.2 on a 
sequence of 10 exposures to get an idea of the focus value, then later
use rather a 5 or 7 exposures sequence around this value with smaller 
steps : 0.1 is fine. 
Experience showed that the V filter Z value is about 0.3 steps above
the R and I value (Usually Z=0.6 for I and R, Z=0.9 for V).

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B - Setting the Z prime focus bonnette
--------------------------------------

The pfocus command sets the Z bonnette to a given value.

usage: 'pfocus z' - Set prime focus Z

Example for the previous sequence, after finding out that the central
point was the best one, the command was entered at the prompt : 

	"pfocus 0.6"

The encoder is not precise enough, consider an error of 0.02 has no
impact on the focus quality.

With no argument, the pfocus command will give the current Z value.

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C - Offsetting the telescope
----------------------------

A simple tool for offsetting the telescope when the prime focus is on.

Example : "pftelofset 3 1.5"

This command will offset 3" East and 1.5" North (use negative values 
for West and South).

Works great for offsets less than 60". 

! Warning : For proper behavior, the prime focus bonnette must be at 0 degree.

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D - Photometric standards script
--------------------------------

The following script (`std' in ~uh8k/bin) will take several exposures (2sec,
4sec and 8sec) on the same image while offsetting the telescope between
each exposures, hence saving a good amount of time. What you will see
is a triple image of your field. Select uncrowned and extended fields 
(like the Landolt fields, AJ104 page 340) to avoid overlaps of stars.
The offset between each field image is 10".

Example : "std"

! Warning : Note that the extension of your file will be "x" not "o".

You might also create you own script based on this one (std).
(and then you will have to source them : "source name_script")

	clicmd etype x
	clicmd etime 2
	clicmd clear
	clicmd go
	clicmd etime 4
	pftelofset 0 10
	clicmd go
	clicmd etime 8
	pftelofset 0 10
	clicmd go
	pftelofset 0 -20
	clicmd readout
	clicmd etype o

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E - Shift-and-Add script
------------------------

This is an example of a script taking several exposures on the same
field while slightly offsetting the telescope between each of them to 
allow removing the CCD cosmetic defaults when combining the images later. 

Note that the wide field corrector induces a strong optical distortion 
and using large offsets (>20'') will force you to correct for the optical 
distortion, something not straightforward.

Example : This script will take six object 10 minutes exposures (field
          K757). The comment is set for each different exposure.
          (this script has to be sourced)

	clicmd etype o
	clicmd etime 600
	clicmd fits comment Sequence of 6 10min exposures on K757
	clicmd go
	pftelofset 10 0
	clicmd fits object K757 10E
	clicmd go
	pftelofset 10 0
	clicmd fits object K757 10E
	clicmd go
	pftelofset -5 10
	clicmd fits object K757 5W 10N
	clicmd go
	pftelofset -10 0
	clicmd fits object K757 10W
	clicmd go
	pftelofset -10 0
	clicmd fits object K757 10W
	clicmd go

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F - Dark exposures script
-------------------------

This is a short reminder on how to write a script for taking
a set of exposures with different parameters.
You just have to "source" it from the neptune prompt. You
will see the commands executing in the log window.

Example : "source dark_seq.scr"

The dark_seq.src file (that you can edit with your favorite editor or
create your own set of scripts) is :

	clicmd etype d
	clicmd etime 4
	clicmd go 4
	clicmd etime 1440
	clicmd go 9
	clicmd etime 900
	clicmd go 9

Which will take four 4sec dark exposures, and nine 1440sec and 900sec 
dark exposures.

For other available commands, type "?" in the command line window (uh8k). 
All these uh8k commands have to be preceded by the 'clicmd' command to
allow passing the uh8k commands to the uh8k software.

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