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#1 john32712

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Posted 01 March 2017 - 09:48 PM

I have had great sucess with MLPT and have two questions which somebody might be able to answer:

 

1. Do you always tweek your Fourier Numbers at the bottom to optimize after a MLPT run?

 

2. I can get 15-20 unguided subs with MLPT. Is anyone getting this without MLPT. Can you create a good enough model with superfit so MLPT becomes unnecessary? Having to perform a MLPT run every time i start a new session will make a remote imaging a pain. I am curious to here what the remote guys are doing....



#2 lukepower

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Posted 02 March 2017 - 11:29 AM

Hi John,

 

the remote guys are basically doing the same what one would locally - but using Teamviewer or the likes.

The better question - and I guess this is what you wanted to know - is what the automation guys are doing.

MLPT is not usable from ACP/Sequence Generator Pro/CCD Commander/<insert your software here>, so either you try your luck with SuperFit or you use a guider (duh!).

 

I personally had some success with SuperFit - it worked as long as the conditions (temperature) were similar over different nights, but the more time between the pointing run and the timaging time, the less it worked. I settled to using a guider for slow corrections with all my systems, and am quite happy with it. MLPT might be more efficient, but not by much.


Lukas Demetz
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www.skygemsobservatories.com
Astro Dolomites Observatory, Skygems Network
Santa Cristina Valgardena, Italy
20" Cassegrain-Newton on ASA DDM85XL


#3 Jay

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Posted 02 March 2017 - 01:09 PM

John,

 

I've never needed to tweak my Fourier numbers after the MLPT. My subs are 20-30 minutes, however, the focal length is under 1000 mm. 

 

All my sessions are done remotely with the sky model (30 - 40 points renewed every 2-4 weeks) and the MLPT. I've tried using only a (larger) sky model (and SuperFit) but haven't been very successful with that. Mostly because of the same reasons Lukas said, conditions change and the model deteriorates over time.

 

The problem with the MPLT is that it cannot be attached to other party software. So you have do it separately if using something else than Autoslew/Sequence. What I'm doing is making the MLPT before every target but running everything else with MaxPilote (e.g. TSX, MaximDL, FocusMax, observatory software, etc.). It's a pain if shooting several targets over the night but quite convenient with 1-2 targets.     

 

Jay



#4 john32712

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Posted 03 March 2017 - 04:41 AM

Lukas and Jay thank you for your response back. I was hoping the answer would be Superfit is all that is necessary. But life is never that easy is it!

 

Like Jay, I have great success with MLPT, but it is a pain to have to run, especially when acquiring multiple targets per night. I have CCDAutopilot (not currently using) and have begun to consider remote imaging. My observatory is only 2.5 hours away from my home, but it would be nice on night when I cannot get away.

 

OK, back to the topic. Yes Lukas you provided me the information I wanted to know. Now you brought up autoguiding. I did autoguide with all my other mounts, Tak, AP, and stopped when I purchased the ASA. I have never tried autoguiding with my DDM85, does it work just like any other mount? I would use Maxim DL to guide with. Are you performing off-axis guiding or using a secondary scope?

 

Correct me if  am wrong here, To do what Jay is doing, He must be up all night at the monitor because MLPT cannot be automated. If you autoguide, you then can truly have an automated session in which CCDAutopilot or ACP can run the show. Right?  The only issue I see here, we bought a mount light years ahead of anything else and we now have to make it like any other mount to go remote...

 

Best Wishes,

 

John



#5 Jay

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Posted 03 March 2017 - 12:36 PM

John,

 

You're corrected... I don't stay up all night long  :)

 

If doing e.g. 2 targets, I'll have to wake up once. I simply wake up at the time needed and do the MLPT run for the new target. It takes couple of minutes and then back to sleep. Everything else is fully automated...

 

Jay 



#6 maxmirot

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Posted 03 March 2017 - 10:52 PM

Sequence is no much fun to run multiple objects  and it is has limited features.

However, I am  having good success with MLPT despite this.

 

I run a new superfit model every 1 or 2 months with 50-100 stars.

I usually can get 10 minutes without MLPT

 

I can improve the error fit by increasing the fourier settings.

The numbers show less error but not much difference in the pointing or tracking.

 

I had problems with guiding using SGP.  What setting in autoslew are you using?

I thinking about adding an OAG with a new Moravain 16200 and then trying guiding again with SGP.

 

I am at 1100 mm FL do you think I can get a guide star on the sensor without a rotator?

What guider cameras are you all using with your OAG?

 

Max



#7 lukepower

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Posted 04 March 2017 - 11:20 AM

John,

 autoguiding with the ASA mounts is easier than with other mounts, as the movements are very smooth and precise. I use very small corrections (Maxim DL aggressiveness around 2-3) and also make infrequent corrections, and raise the minimum move to higher values. With this, it is very easy to guide and forget completely about MLPT and the likes.


Lukas Demetz
------------
www.skygemsobservatories.com
Astro Dolomites Observatory, Skygems Network
Santa Cristina Valgardena, Italy
20" Cassegrain-Newton on ASA DDM85XL


#8 john32712

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Posted 05 March 2017 - 10:31 PM

Lukas,

 

Thanks again....

 

John



#9 Waldemar

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Posted 06 March 2017 - 12:21 PM

John,

 autoguiding with the ASA mounts is easier than with other mounts, as the movements are very smooth and precise. I use very small corrections (Maxim DL aggressiveness around 2-3) and also make infrequent corrections, and raise the minimum move to higher values. With this, it is very easy to guide and forget completely about MLPT and the likes.

 

Yep, that is what I am doing, too. Just using a SX maxi Filterwheel with build in OAG and LodeStar 2 guidecamera. No MLPT or Sequence ...

And as a bonus you can use SGP as well... I really think the no guiding possibility is not that important, other features of the mount are far more interesting.

Saves a lot of hassle  to use a guiding cam! MaxIm as well as SGP are absolutely capable of replacing Sequence totally. Not to talk about FocusMax...

Makes life a lot easier!


Waldemar
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Mount: DDM85 Standard 12V ; Telescopes: TEC140 + 140FF + Quad TCC ; Celestron RASA; TMB 92SS + 27TVPH Cameras: ZWO ASI 174MM cool; SBIG STF8300M; ATIK4120EX; TRIUS SX-36
Filters: Astronomik and Baader NB + RGB; Lunt double stack 75 mm unobstructed signature series + BF 3400; Dutch weather and light polluted skies.  

#10 john32712

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Posted 07 March 2017 - 12:10 AM

Thanks for the additional info Waldemar. I"ll have to try it!

 

John



#11 Waldemar

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Posted 07 March 2017 - 08:23 AM

You're welcome, John. You won't regret trying


Waldemar
--------------
Mount: DDM85 Standard 12V ; Telescopes: TEC140 + 140FF + Quad TCC ; Celestron RASA; TMB 92SS + 27TVPH Cameras: ZWO ASI 174MM cool; SBIG STF8300M; ATIK4120EX; TRIUS SX-36
Filters: Astronomik and Baader NB + RGB; Lunt double stack 75 mm unobstructed signature series + BF 3400; Dutch weather and light polluted skies.  

#12 maxmirot

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Posted 08 March 2017 - 04:18 AM

What settings are you using for autoslew and PHD2 ? I have problems with SGP guiding.

 

Max






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