Advice needed: G11 vs. Mach1

Hi joelshort,
In France Mach1 GTO with keypad is about 8000€ and 10Micron about 8300€…
Michel.

True. A Mach1 with optional keypad is closer in price, but the 10Micron is still at least $1000 more. Regardless, my point is that I need to buy used because I cannot afford either a new AP or new 10Micron.

Little late to the dance, @joelshort, but as another data point, I have had very good luck running the AP1100/GTOCP3/SGPro combination. No problem at all with PHD2 pulseguiding. Automated meridian flips delayed, early, or on schedule managed by SGP all seem to work for me. I never make a data model since I am a nomadic observer, just one plate solve and recal after setup and subsequent slews are very accurate (provided you have a decent polar alignment). No issues for me with the JNOW/J2000 stuff either… that appears to be fully sorted.

I also use AP’s APCC, since I was used to using EQMOD with my old mount, and to me, it has some of the same features.

I have never owned a Gemini as a comparison point, but this mount was as close to plug and play with SGP as I could imagine.

Best regards,
Craig

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Thanks Craig. MY Mach1GTO is on it’s way and should arrive in a few days.
:slight_smile:

One quick question, that I can also ask on the AP user group, what is the
difference between RECAL and SYNC as AP understands it? I’ve seen several
other people refer to RECAL and yet I don’t know what it means, but it
seems like it might be important.

Hi Joel,

Have you read the Keypad 4.12 manual? It’s well described there. It’s kind of strange it’s not described in “Mach1GTO” operating manual. There is a section that describes very well differences between SYNC and RCAL and when to use them and when not to use them. See page 61 and 62. Note that the word “RCAL” is only mentioned once in the manual and uses the word “Re-calibrate” instead which is the same thing.

http://www.astro-physics.com/tech_support/mounts/keypad_v412.pdf

If you are not clear about SYNC and RCAL after reading the manual, please let us know. It’s kind hard to describe in few words here.

My bottom line is to avoid using “SYNC” and always use “RCAL”. Unparking from Reference Park 1 automatically “SYNC” the mount. So slewing to a star after unparking, center the star and that’s when you “RCAL” on that star. You can refine pointing accuracy by slewing to a known star nearest to your target DSO, “RCAL” on that star and finally slew to your target DSO and it will be in FOV of your camera. You can even “RCAL” on an object with counterweight higher than the scope. But if you SYNC on an object with counterweight higher than the scope, the scope will collide with the pier. So that’s why you want to avoid using “SYNC”.

Peter

Joel,

From a slightly different perspective: as an SGP + AP mount user, I can say that I have never needed to know the difference between SYNC and RCAL! Though just now out of curiosity I read up about it here.

I have a permanent setup and I keep the keypad unplugged from the mount (no need for it whatsoever). The mount is exclusively controlled by the ASCOM driver and I do all my syncing via SGP (recalibrating in AP parlance!). In that workflow SYNC vs. RCAL never comes into play since SGP is calling the ASCOM SyncToCoordinates function which the AP ASCOM driver interprets under the covers as a request to recalibrate. From an SGP or ASCOM user perspective, it is a hidden detail that I have been blissfully ignoring since I got the mount.

Enjoy the new mount!

Andy

Thanks Peter and Andy. I’ll do some reading. It’s good to hear that SGP
calls the RCAL and that the keypad isn’t necessary. I’ll probably try to
sell the keypad to raise some funds for the mount purchase since I’ll be
using the mount exclusively for imaging with the ascom driver. Now I just
have to wait…

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Actually SGP calls SYNC and A-P ASCOM driver converts SYNC to RCAL only if the check box for “Convert SYNC to RCAL” is checked in A-P V2 ASCOM driver.

The link Andy provided pretty much said the same thing as in Keypad 4.12 manual but in different words. It would be good to read both documents to get better understanding.

I believe A-P is planning to remove the SYNC/RCAL confusion when CP4 is released. I think they will use a single word and probably will use SYNC and no longer use RCAL. I think new SYNC will behave more or less like current RCAL. If this is the case, then it sounds like they will have to update the Keypad. New CP4 will require new A-P ASCOM driver which is currently in Beta (V5.08.xx). Beta version should work with CP3 but I would wait till it’s stable and continue to use v5.07.02 driver. According to release notes for Beta version is it’s a major re-write in the code.

Peter

I’ve read through the keypad manual, admittedly very quickly. It’s rather
bewildering to be honest. I learn better by doing so I’ll probably need to
spend lots of time indoors with the mount before taking it out. I am
currently reading the ascom instructions on RGralak’s site and will read
that more carefully as I intend to primarily use the ascom driver.

As this is no longer a SGP discussion I’ll ask any more questions on the AP
yahoo user groups. Thanks Peter, Andy and all for your input so far.

Joel,

I can answer this if you want, but as you say, perhaps not here.

Suffice to say with the GTOCP3 and the AP ASCOM driver, I have always used the option to convert “syncs” to “recals.” The initial “sync” does things like defining which side of RA contains the telescope and which side contains the CW. Once this is defined, it should not be changed. The “recal” simply tweaks the position of where the mount thinks it is pointed to where it is actually pointed. This is the behavior you want from any “sync” sent from SGP.

Like Andy, I find little occasion to use the keypad. I always think I will, but I don’t. In practice, I always end up initializing from the laptop.

Best regards, and congratulations on the new mount!
Craig

Peter, where are you getting info like this about CP4? Scouring the yahoo groups I’m not seeing much. AP says it is planning to take “pre orders” in the middle of Feb. In your experience, how long is there between “pre orders” and actual shipment?

From either ap-gto or ap-ug Yahoo Groups. It’s P.I.T.A. to search for information from Yahoo Groups.

Between “pre-oders” and actual shipment for CP4 or any A-P products? For any A-P products, it varies from a few months to a few years. For CP4, I have no idea.

Peter

Oh man, I hope it’s not years or even months. Early on they sounded like
they might be ready to ship by December 2015, so I hope once they take pre
orders it will be a matter of weeks.

And yes, searching the yahoo groups is ridiculous. Thanks Peter.

I misunderstood the “preorder” part. I thought it was the promised date of when preoder will begin because they have been delaying “preorder” dates. So to answer your question about this is I really don’t know. When I “preordered” my A-P1100, it took about three months to get it but that’s a much more complicated part than CP4.

Peter