Re: Mach 2 First Impressions (Quick Post)

Bill Long

The guided performance was great for long extended periods. Seeing last night was maybe 2/5. Not all that great. I did some wide field m106 without the guider running and the frames were excellent. In my experience with a model and encoders the broadband data is usually gravy.

My jokes about the 1100 should be called out again. It works perfectly, and the Mach 2 is it's excellent little brother!

From: <> on behalf of Cheng-Yang Tan via <cytan299@...>
Sent: Thursday, March 11, 2021 6:35 AM
To: AP-GTO Groups. io <>; <>
Subject: Re: [ap-gto] Mach 2 First Impressions (Quick Post)
Hi Bill,
   You said you were joking about the AP1100, I certainly hope so :)

   It's really good to get total rms error below 0.3". But from my experience, I can get this type of error both with my Mach1 and AP1100AE, but that's only for short periods for my Bortle 6-7 site, like for about 15 min. 

  Do you consistently get < 0.3" at your site?

  And I did swap my AP130GT focuser with a NiteCrawle for zero backlash auto-focusing. I also need the camera to match images from the same object taken on different nights (which can be 1 year apart :) ). I need to do this because I set up every night and the image frames can be 5 deg rotated w.r.t. images from the first night.


On Thursday, March 11, 2021, 12:47:51 AM CST, Bill Long <bill@...> wrote:

Bill Long has shared a OneDrive file with you. To view it, click the link below.
I have more work to do, but here is a PHD2 graph in its entirety from the Mach 2, 5 min Lum sub. No model, just PHD2 calibration. 

Sub here:

Note that there is a little tilt in this, not much, but was part of the test. I was testing whether or not the AP130GTX focuser was causing any sag in the train with the following gear:

FLI PL16803
7 x Chroma LRGB + SHO 3nm
Optec Sagitta OAG
Astro-Physics 133FF for GTX

My findings here show that the NiteCrawler focuser shows the exact same tilt pattern that the AP 130 GTX focuser shows. In both cases it is extremely minor and most imagers would not even know it was there.

That is an incredibly heavy imaging system and the GTX focuser was all the part that the NiteCrawler was. So, if you have a GTX, dont bother replacing your focuser. 🙂 

More data to come, as I have a model going, but so far I am impressed. My 1100 with encoders does not perform as well as this Mach 2. Maybe I should send it in? 😳 


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