Robert Exon wrote:

> Hi all,
> I have been training the PEC on my 10" f10 LX200 using a Meade 9mm
> illuminated eyepeice and a 2x barlows lens. After training I remove the
> barlow lens and watch the star through one 8 min cycle. After several
> attempts I was able to train the PEC well enough so that the star will stay
> within the lines of the small center box with out the barlows lens. My
> questions are as follows:
>
> 1) After training the star seems to go back and forth inside the box
> continually throughout the 8 min cycle. Is this alright or will this show up
> on film photos taken at f6?
>

Hmmmm...let's see, at 1600mm the box is 8.2 arc/sec between the lines, so that's
your F/6.3 number. For you 10" at F/10 it's (1600*8.2)/2500 which would be 5.2
arc/sec. With the barlow you are training at half that, or at 2.6 arc/sec
between the lines. So your after training PEC is 5.2 arc/sec peak to peak. I
would say that if you are staying in the box at F/10, you are probably ok to
photo at f/6, but I bow to LX200 owners opinions.

> 2)What is the arc second measurement between the lines of this small box in
> the center of the 9mm eyepeice at f10 and f6?
>

See previous response.

> 3)As far as the initial number of 21600 is concerned should I try to obtain
> a number as close to this as possible after training and updating? I now
> have 21616 but have had it as close as 21601.
>

Don't worry about it, that just means you are going to drift slightly after the
8 min. period, you are going to have to guide somehow anyway, so you will
correct for this drift automatically during the guiding.

> I don't know about the rest of you but I there are several places on my worm
> gear where the star moves out of the center so fast I can not correct fast
> enough to keep the star in the center. I wish the PEC would play back what
> it has already learned while you update. Thanks for any responses.
>

That's what we all concluded a couple of weeks ago.

Have a nice day!
m.

> Robert

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