STV and ST-4 was Re: [APML] 2 More ST-4 questions

["westergren" <westergren@netzero.net>]

Alen,

I have used both the ST-4 and STV, and helped several friends get ST-4's and
STV's working on their mounts.  My personal experience is that the STV is
greatly easier to use and much more useful overall than the ST-4 (both
box-only and with a computer display).  But "ease of use" can mean different
things.  If the capability (and complexity) is greater (for the STV), then
the learning curve is more significant and the new user will probably say
it's harder to use.

I think the STV is easier to use because the larger chip and the display
make finding a guide star and focusing much easier.  Since the STV can do
much more than just guide, it has many controls and menus, so I spend a few
moments in focus mode to find and focus the STV, then Calibrate on my guide
star, then start tracking.  Each of those modes is a different button to
push, and depending on the guide star and sky factors, I may choose to
change the exposure settings.

Much of the frustration and time consuming efforts I have spent with both
the ST-4 and STV have been mount related, not the autoguider.  Mounts that
have been used for manual guiding (with guiding errors about 3 to 5 arc
second accuracy) don't always behave as well as expected when the CCD is
capable of sub-arc second accuracy.  It takes tuning of the autoguider
settings (gain, movement calibration, exposure, backlash control,
aggressiveness, etc). Tuning of the mount for proper tracking speeds (if
settable), backlash, gear periodic error, mirror flop, balance, drag of
cables, etc can make an autoguider either work very well or not at all.
Once the settings have been found for both the autoguider and mount to work
together, subsequent use goes well (until we tinker with the settings again
or something breaks or gets forgotten).

I use my STV for much more than and autoguider.  It is my finder and
composition aid for my 35mm camera, it aids in polar aligning (drift), it
indicates the quality of the sky, it helps troubleshoot mount tracking
problems, it takes pictures of deep sky, planets, and the moon.  Is it
perfect? No! But I still like it, and I'm glad I bought it when it first
came out, so I have several years use with it.

Don
>
> I don't have an ST4 or STV but I have friends that
> do. After watching my friend with the STV fuss with
> it all night and talk about what the next software
> upgrade will fix, I think the thing is too darn
> fancy for its own good - at least when used strictly
> as an autoguider. It is not IMHO the true logical
> successor to the ST4. When is someone, if not SBIG,
> going to release that true successor? (Too bad Meade
> decided to rest on what few CCD laurels it garnered.
> All its CCD camera designs are *ancient*. And too
> bad Apogee managed to make a joke out of the LISAA.
> Their autoguider concept look promising.)
>
> (Just the grumblings of someone who wants to buy an
> autoguider and is disappointed that the "best" one
> is still a discontinued model.)


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