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imaging with the Mach-1, newbie question...

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#1 CounterWeight

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Posted 30 April 2010 - 11:52 AM

Ok, I'm not lazy - just have had nearly no time on the mount yet past the setting up, tearing down and trying PA without polar scope, learning way around menuing, the simple stuff. The 'curse' is alive and well here.

Here is my question. When imaging I usually in the past sent my goto to an object and if reasonably centered verified critical focus and imaged on. That's the easy case and I think it'll be easy again with this mount.

Sometimes -lets say M81/M82, or Leo Triplet, or NGC7331 / Stephans Quintet - I locate a reference and then manualy slew the mount to get the objects in the image and image on... with the Mach1, since I have manually slewed... is there a way to set that as a tracking point or reference? Should I recalibrate on that point? - sync on it? not do either? For long series that might include a flip is there a best known method to regain the relative image orientation that doesn't involve a more convoluted solution involving pattern matching and etc...?




Thanks :)

#2 jgw12936

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Posted 30 April 2010 - 12:55 PM

Hi Jim,

All good questions. I recommend you read theGTO keypad manual for the differences between sync and re-calibrate. They are different. Basically sync is usually used early in an imaging or viewing session to tell the mount where it is, it starts from scratch and uses the position in the keypad or in my case I use The Sky 6, and tells the mount here is where I am. Usually when I use this function I start of by resuming from park or by placing the mount in park position 1 and resuming from park position 1. Then I will use the sky and point to a bright known star. I then use my CCD camera and crosshairs and the keypad to place the star in the center of my crosshairs and then choose "sync" from within The Sky 6. The Mach1 is so accurate in its' pointing if you have the polar alignment and all the baseline values input correctly, that I would usually just use the Sky FOV to choose my target and slew, do a quick binned image to make sure I was pointing correctly and then start imaging.
If you use re-calibrate this is described as a "tweak", the mount calibrates the difference between where it thinks it is, and where it is pointing, it does not start over. Both Sync and re-calibrate have their place, in fact if you use Ray Gralek's new ASCOM driver, there is an option to always change syncs to re-calibrate (and it says this is recommended. There are some caveats when using the sync command, you want to be polar aligned, you want your counterweight shaft NOT to be pointing up, don't want your meridian delay function on and a few more.

I have a permenant setup so my night always starts like this: Turn everything on, resume from park, slew to a known bright star near where I plan to image if possibe, use maxim to place the star on the crosshairs and sync via the sky (I am using the 2.0 ASCOM drivers and have all my baseline stuff input correctly) slew to my target, take a binned exosure to verify framing, run focus max and start imaging.
You can also use platesolving to verify your position and to sync your mount. If you have Maxim and pinpoint simply use the same procedure above, point to an area with lots of stars, take an eposure, platesolve and sync the mount.

Hope this helps, don't forget to read pages 62-65 of the keypad manual.

Jim

#3 CounterWeight

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Posted 30 April 2010 - 09:33 PM

Thanks Jim,

Yes, ive been going over those pages, both the easy and detailed versions. Don't see an ability to save a point in the H/C, and it seems everything says if I manually slew the mount and select the recal, I'd have to re-align later if I want to re-orient the cal back to normal? Dont see anywhere to save a data co-ord and reacall it? Is it there and I'm just missing it?

I'm trying to figure out all this (if it's possible) without connecting a computer (or buying / upgrading any other software like Maxim). I have a computer I use for capture and planetarium / info, and have SkyTools 3 pro (like it much more than theSky).

#4 jgw12936

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Posted 30 April 2010 - 10:03 PM

Hi Jim,

I think I understand your question now. You want to image the objectS M81 and M82, so the center of you FOV will be in the middle. Is this correct? If so, then the answer is you don't need to do anything, if you frame your objects using the keypad, The mount knows where it is. If a meridian flip needs to occur, the mount will do its thing and and go back to the RA and DEC. The only times I use a sync or re-calibrate are with my initial slew, or when I change to a different part of the sky, say from a target in the north to a target in the sounth.

Jim

#5 Mike Clemens

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Posted 30 April 2010 - 11:49 PM

a computer, even a tiny netbook would free you from these worries by letting you run a planetarium program.

Before I used the computer though with my own GTO mount I would do as you are desiring. As I recall there is way to call up the current RA and DEC and have it cache it for easy re-GOTO. I cannot remember the key sequence but I remember framing an object, slewing to focus stars, and then going right back to my previously framed coords.

I THINK your answer is on pg 34 of the GTO manual at the bottom under "Custom RA and DEC coordinates", press ??NEXT>??? and the coords will appear ? plz tell if you find it

#6 jgw12936

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Posted 01 May 2010 - 08:08 AM

I have not used Sky Tools 3, but on their website they say the professional version will control the telescope via ASCOM, you could use the AP 2.0 ASCOM driver and control the mount.

Jim

#7 CounterWeight

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Posted 01 May 2010 - 09:58 AM

Mike, thank you, found it :). Anyone else interested in this it's on pages 39-40 of the HC manual, and as Mike noted, under the heading of Custom RA and DEC Coordinates. Unclear from the manual language but the save feature may have been changed from previous versions?

Jim, Thanks - I'm going to try ST3pro out at some point, but only after I use every nook and cranny of the hand controller and know it by heart. I am a learn and know by doing type person, so the way our weather is, it may be a few months.

I think NOAA/NWS just cut-copy-paste this forecast until mid ~June...

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#8 DavidTrap

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Posted 03 May 2010 - 07:24 AM

Hi,

My Mach1 has only had two outings, so I'm new too.

Just remember if your scopes are not "orthogonal", when you do a meridian flip you will need to recalibrate the scope on a known object before you went back to that point via your planetarium software.

DT

#9 Mike Clemens

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Posted 05 May 2010 - 10:40 PM

unless your planetarium can plate-solve. I do a single plate solve after a flip and everything is dead accurate






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