From: "gaffney.mark" <markgaffney@mac.com>

Date: February 10, 2008 5:03:58 PM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: Focusing

--- In Astro_IIDC@yahoogroups.com, Milton Aupperle <milton@...> wrote:

Hi Guys;

The main issue is that unless I have the hardware in house to work  

with I won't even bother trying,  and to have the hardware in house  

means I need to spend around $800+ USD just for this one case.

First off autofocus has the same mechanical / electrical "fun" factor  

as as guiding does, which is horribly complex. Almost all of the  

Focusers use serial port controls, which means I need to handle that  

as well as the guiding code and make sure they don't interact.  

Secondly most of the focusers have temperature sensors that require  

calibration so that they compensate for temperature changes which  

affect focus.

Secondly, I've done remote debugging for hardware trial and error in  

the past (i.e. cameras, USB, FireWire, CardBus, Serial Ports,  

Parallel port etc.) and it's a complete PITA (Pain In The A**) to do.  

Basically I change something in code, you try it out (maybe 1 to 6  

weeks later because of weather or your schedule or whatever other  

delays there are), and then send me back a feedback report. Then I  

make another "change" when I have time and we go though this cycle on  

and on and on until we both get fed up with it and give up after 8  

months of farting around. Where as if I have it in house maybe a  

month goes buy before I have something debugged enough to test with,  

assuming I'm not scrambling around looking for consulting work and  

have the time to do this.

And thirdly, to buy those products (i.e focuser, motors, controllers,  

hubs and parts for my C8) will set me back $$700 to $850 USD + taxes,  

assuming that the company will provide me with all the information to  

talk to it. I make less than $45 CDN a copy on Astro IIDC (after  

deductions for credit cards and service fees and taxes) so to do this  

means I need to sell 20 to 30 copies of Astro IIDC to just pay for  

the hardware. Then i have probably a month or twos time writing and  

testing all the software, which is time away from earning real income  

consulting and working for other companies.

Lastly I need to repeat all of the above for each product that needs  

to be supported (i.e RoboFocus, JMI etc.), because there are multiple  

systems out there and not everyone is using one single unit.

And ASCOM Drivers don't help much this case either,  because all they  

are is "drivers" which you still have to manipulate and write all the  

functional code for it, assuming they now create both PowerPC and x86  

versions of the drivers as at least 70% of my user base is still  

PowerPC. Basically it means sending a command over the Serial Port to  

whatever hardware I'm supposed to be talking to and then hoping that  

the company that made the product is factual in telling you what to  

send, how often to send it and if there are any "bugs" when sending  

too it (timing, sequences etc.).

So basically it isn't going to happen unless I suddenly win a lottery  

to buy all the hardware toys to work with and retire so I can do this  

full time. Sales of Astro IIDC pay a few bills, but they don't even  

pay for basic hardware expenses like computers, camera and other  

hardware for testing against.

Hope that clarifies things.

Milton Aupperle

On 10-Feb-08, at 2:39 PM, Joe Breault wrote:

Dear Mark, Alan and Milton,

Thanks for your help and advice.

Re: solar washout: that is a great idea Alan, thanks for the tip. I'll

try it. Glad that screen focusing works well.

Milton, any chance that future editions of the Astro IIDC can access

auto focus hardware using the FWHM/HFD or sharpness indicator in a

feedback loop to achieve onging critical focus? I sae that  

starlight (I

have a 3.5" FT on my scope) came out with a motorized add on

(http://www.starlightinstruments.com/digital-FTS.html) that can  

control

the focuser through an ASCOM compliant software interface. Mark

mentioned that ASCOM is PC based, though I run parallels within my

macbook for windows programs - not sure how that would interface with

Astro IIDC in OSX. ASCOM had a 2008 announcement they would develop

drivers for mac (http://forums.dc3.com/showthread.php?t=2729) which

might make this type of plug in for Astro IIDC easier.

Thanks again to all for your helpful insights

Joe

If Joe has some way of running Windows on his Mac, then focusing the telescope should 

be an independent process to those already provided by Astro IIDC for CCD camera 

control. I haven`t tried this in practise as I said but Joe should be able to switch readily 

from his focuser window ( running through Ascom on Windows) to Astro IIDC on Mac OS X. 

I tried downloading Ascom I think with Safari but the file wouldn`t transfer readily to those 

I have running through Virtual PC for Mac, that`s why I`m suggesting the download be 

done with Internet Explorer (if available!) Mark.