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The star is centered in the finder, but I don't see it through the eyepiece.
Everything was fine, but I just slewed, and now I don't see anything. What happened?
Something's wrong with CCDsoft or the Sky, but I don't know what. Please give me random advice.
Downloading the image takes a long time. I don't have all night.
I am using the "Move Telescope" pad in CCDsoft, but nothing is happening. Enlighten me.
What does the "color" tab do in CCDsoft. I like colors.
Finder Issues
There are a few possibilities. It might sound obvious, but check the
end of the scope for a lens cap. We don't normally use them but they
exist. Next, look to see if there is a condensate on the lens.
Shining a light indirectly at the lens should reveal this. If the
star is very badly focused AND the aperture is fogged up, it might
not show up. Most likely, however, someone touched the finder scope,
misaligning it. If you are that person, shame on you. Regardless, it
is a tricky process to get everything aligned again. See a TA for
help. If none are around, here is the basic procedure:
You need to find a bright star in the eyepiece. It's tough to do, but
sight down the scope and align as best you can by eye. Use the
biggest size lens you can find, to increase your field of view. When
that is centered, make sure the RA and Dec knobs are locked. Loosen
and tighten the thumb screws around the finder scope until the star
is also in the center of the finder scope. If you can't see the
crosshairs on the finder, have someone hold a light at an angle such
that it illuminates the crosshairs without overshadowing the star. It
is not as easy as it sounds. Good luck.
Missing Image
First, does CCDsoft detect the camera? Check the "status"
bar at the bottom of the main CCDsoft menu. If it says that it is
connected, then refer above. If it is not
connected, check the power to the CCD camera. One of the cameras
seems to lose its power connection sometimes. Slewing can spur this,
as the wire is torqued slightly. Check all the other connections as
well. There should be a wire running from the camera to the computer,
and one running from the scope to the computer. Make sure they're
plugged in.
Missed Slew
There are a few likely explanations. First, how long was the slew?
Though these scopes are precisely mounted, slews across a long
stretch of sky can cause the star to be slightly out of the CCD
image. Try going back (you should be able to get back to the place
where you came from) and then slewing to an intermediate destination,
between the source object and the object that you are slewing to.
Once on the intermediate object, re-center, re-sync (see procedure
sections 5b and the Bonus Direction for instructions on how to
do this) and then complete the slew.
Another likely explanation is that the telescope is not stably
mounted. The screws on the back of the scope must be tightened
completely; any breathing room leads to slight misalignments. Tighten
the screws to be sure they're not loose.
The telescopes are also aligned so that they work on specific piers.
While the effects of putting a scope on the wrong pier are not
documented, it is possible that they could lead to slight alignment
problems. Check the documentation in the observatory to see which
scope goes where and try again.
Finally, check to make sure that the power cord is still plugged in.
The torque from a slew could have wrenched it out of place.
I hate focusing.
Yeah, focusing is a pain. Here are a few tips:
1- Backlash might be a problem. When you change from focusing
in to focusing out (or vice versa) the autofocuser does not
transition smoothly. A large number of focus units (around 500) are
required to change direction, before any new focusing in that
direction is attempted. Take that into account when you focus. See the
procedure section 7c for details.
2- Check to see if there is ice on the lens. That tends to
make focusing nearly impossible. Luckily, a hair dryer works to
remove the ice. Talk to a TA or instructor about doing this.
3- Relax. Seriously. Go get a drink of water. Come back and
try again in 2 minutes. It's a hard task, trying to force it makes it harder.
4- Give the camera time to update. After each focus step,
pause for 5-10 seconds to allow the changes to be reflected by the
new downloaded image. You might focus right past ideal by taking too long.
5- Try changing the background and range. See the procedure
for more details.
General Questions
Are you logged in as administrator? Go back and check the procedure!
Slow Download
There are two things to try, both of which will decrease download
speed. First, change the bin size in the CCD options menu to 3x3
instead of 1x1. This step is documented in the instructions.
Also, you can change the size of the area that you are looking at.
Select "subframe" and enclose a region surrounding the
object that you are looking at. Be sure not to make it too small, as
you will become disoriented looking at it too close up. Both of these
methods decrease the amount of units of data needed to be processed,
thus speeding up the download time.
I can't move
This is an unfortunate, though documented problem. CCDsoft does not
have control over the movement of the telescope. In order to move,
you must use "The Sky"'s slewing tool. The "Bonus
Directions" in the procedure
describes how to do this.
Pretty Colors
Yeah, I don't know. Colors are nice, but meaningless for most of what
we use these cameras for. A CCD camera only sees a count of the
number of incident photons. In order to gain any information on
colors of objects, you must change the filter and see if there is any
difference in incident light due to filtering.
Find the Needle in the Haystack
First, read 8b in the procedure.
It is possible that you have the telescope set too sensitively. When
set at this level of sensitivity, the image you see does not discern
between high levels of incident light and lower levels. Both show up
as white on the screen. You can fix this by following the directions
in the procedure.
Save As?
Ask your instructor or TA for specific naming conventions for files.
The astronomy 101/102 students should save their files as *.st7 type,
as the programs we use to process them expect that file type.