#iexos-100 #polaralignment #astrophotography #iEXOS-100 #astrophotography #polaralignment


Derrell Oliver
 

Hey Guys,
I need some advice... I am having trouble getting GoTo objects into my field of view, last night I tried to image M101 & M51, I had Polaris centered in the Alignment Tunnel then did a two star alignment using Capella & Dubhe, then slewed to M101, tried a few 30s exposures @ iso1600 and never got a preview with M101 on my camera chip, I repeated the alignment again then slewed to M51, still no luck finding it, I cant see it with my finder scope due to light pollution.. I have had good results with M82 & M81 a few weeks back and of course M42 & M43... when I have the mount polar aligned should Polaris be centered in my Finder scope and the telescopes eye piece ? I think i'm having trouble repeating an accurate home or park position.
Any Ideas ?
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Taro
 

Hi Derrell

Before you go to M101,
(1) you go to Mizar
(2)Set Mizar in your Camera center by direction button.
(3)click Sync button.
(4)You go to M101
Maybe you can get M101 in you camera FV
M51 also, go to and sync near star first.

I use this way every time. and I success every time.
Hope you get nice M101 and M51.
Clear sky!!

2020年4月3日(金) 23:23 Derrell Oliver <mtbkr123@...>:

Hey Guys,
I need some advice... I am having trouble getting GoTo objects into my field of view, last night I tried to image M101 & M51, I had Polaris centered in the Alignment Tunnel then did a two star alignment using Capella & Dubhe, then slewed to M101, tried a few 30s exposures @ iso1600 and never got a preview with M101 on my camera chip, I repeated the alignment again then slewed to M51, still no luck finding it, I cant see it with my finder scope due to light pollution.. I have had good results with M82 & M81 a few weeks back and of course M42 & M43... when I have the mount polar aligned should Polaris be centered in my Finder scope and the telescopes eye piece ? I think i'm having trouble repeating an accurate home or park position.
Any Ideas ?
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


--
Living in  Pattaya Thailand
Scope: Celestron 6SE,WO Z61,WO RedCat51, SVBONY SV48
CCD: SONY Alfa7Sii,SONY QX1, PENTAX KP,ASI 178MC,ASI 120MC-S
          SAMSUNG SCB2000N
MOUNT: Celestron AVX,Celestorn SE+Wedge,iEXOS-100,SW Star Adventure
FILTER: HA,Oiii,OPTLONG L-PRO,OPTLONG L-eNhance, Etc
SubLens: 2" Flattener, 2" 2XBarlow, 2" F/0.5 Reducer, SCT F/0.63 Reducer
ETC: GPS,StarSence,iPolar


Derrell Oliver
 

Thanks Taro !!
I will try that.
Thanks again.
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Chris Tardif
 

Are you using the tablet app Explore Stars or ASCOM  on a PC?
Chris



--
Mounts: Explore Scientific IEXOS-100 w Celestron CG5 tripod, iOptron CEM 40
Scopes: Explore Scientific FCD-100 ED-102CF, Various Canon lenses, ZWO mini-guidescope, StarField 60mm guide-scope.
Camera: ASI120MM Mini (mono), Altair GPCAM 130
Control PC: Intel NUC
Loc: 44 -79


Derrell Oliver
 

Hi Chris,
At the moment i am using the Explore Stars on a Android Tablet.
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


brian skinner
 

Hi Derrell, I personally don't use the alignment tunnel, I believe it is only of real use when used with a polar scope. Try a purely mechanical approach to polar alignment before powering the mount up.
I, by line of site, position the mount roughly at polaris, turn my camera live view on then adjust the alt knob until polaris is vertically in the viewfinder than move the mount left or right to get it horizontally centred. When this is achieved you are, in my experience, sufficiently polar aligned. You can use a polar algnment app which will indicate how far off Polaris is from the earths true rotational axis but if you do a three star alignment I find my targets are at least in my live view screen and with the UPLR buttons easily centred before hitting enter. My final target is usually invisible to the view finder and but on taking a trial photo, again usually in view, or at least any pointer stars, although not always centred. Obviously you need to hit park, reset alignment and enter your gps coordinates before commencing the alignment procedure.
It does seem odd that some targets are fine but others not, have you got full battery power?
Hope that helps, kind regards, Brian

On Fri, 3 Apr 2020, 17:23 Derrell Oliver, <mtbkr123@...> wrote:
Hey Guys,
I need some advice... I am having trouble getting GoTo objects into my field of view, last night I tried to image M101 & M51, I had Polaris centered in the Alignment Tunnel then did a two star alignment using Capella & Dubhe, then slewed to M101, tried a few 30s exposures @ iso1600 and never got a preview with M101 on my camera chip, I repeated the alignment again then slewed to M51, still no luck finding it, I cant see it with my finder scope due to light pollution.. I have had good results with M82 & M81 a few weeks back and of course M42 & M43... when I have the mount polar aligned should Polaris be centered in my Finder scope and the telescopes eye piece ? I think i'm having trouble repeating an accurate home or park position.
Any Ideas ?
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Wes Mcdonald
 

Darrell:

So getting accurate gotos is probably the toughest part because they depend on so many variables.  But it can be done.

1.  When you are at polar home, Polaris should not be centered in the tube or finder scope.  Polaris is 2/3 of a a degree away from the NCP.  Depending on your field of view in your camera, that alone could put you out.  Make sure though that your finder scope and main camera are aligned on the same optical axis.  If not you wont really know where your scope is pointing.

2.  I have a procedure for finding polar home posted in the flies section of the main subgroup.  It will get you a polar home position you can bank on.  Note it does require that you have a level mount.  Also, for the polar home found, you must always level you mount upon each use as precisely as possible the way it was when you found the polar home.  

3.  If the mount is not level, your gotos will be wrong, even though you get polar aligned.

4.  The dec home error you might have on any one start up gets reflected through to your gotos even after a 2 star alignment.  So get that home position right.

5.  Before you try imaging, I would suggest you perform a goto to a bright star nearby the deep space object.   Center that star in the finder using your left/right/up/down arrows.   Then perform a SYNC.  At that point the scope should do a nice goto in a region around the that point almost regardless of the other errors involved in getting things just right.

6.  As you are interested in doing astrophotography, I suggest you work toward using ASCOM and employ plate solving to center your FOV.  It works like a charm, and you never have to worry about finding the desired object dead center in your camera.  Fact is Explorestars is not meant to be a vehicle for doing astrophotography anyhow.  

7.  If you level the mount in your customary setup position and perform the finding polar home position there, you can mark the place where the tripod legs sit.  If you never change the leg length after that, and alswaysput the scope in the same exact position your polar home position will be pretty good each time.

8.  Another thing you can try is to use Sharpcap to get your scope polar aligned.  If you do this, you do not need to do a virtual alignment with Explorestars.  Sharpcap works with your astro camera.  Not sure if it works with all, but you should be able to read about it.  Others here use it and can assist.  You will still need to establish level and polar home though.

9.  Finally, Explorestars 2-3 star alignment can be tricky.  You must ensure the stars you use the actual ones you centered.  Also the stars should be separated.  Dubhe and Capella look like they should work fine.

10.  Really finally, make sure your time is set correctly in your tablet, and that the site location is correct.   And also the mount type.  Sounds like these are fine given your success with other objects. 

Wes.


--
Wes, Southport NC
PMC-8, ES ED 127, 10" LX200GPS, Astro-Tech 8" Newt, ETX-90
Polemaster, Orion ST-80 and SAG
Electrical Engineer, Retired


Derrell Oliver
 

Hi Brian,
I will try your alignment suggestions using the live view on the camera, I've been using an illuminated reticle eyepiece
for alignment and I'm using the Explore Scientific USB Power Bank so power is not an issue.
Thanks for the tips !!
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Derrell Oliver
 

Thanks Wes,
I downloaded APT tools last night, going to download the ASCOM drivers today and try that method, I have 
read a lot of good things about it.
I will definitely look up your Polar Home file and do that. 
Thanks for all the help !!

Derrell.

--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Wes Mcdonald
 

Darrell:

APT has the plate solving module in it, once you load all that.  It works pretty well.

Good luck.

Wes.


On Sat, Apr 4, 2020 at 10:24 AM Derrell Oliver <mtbkr123@...> wrote:
Thanks Wes,
I downloaded APT tools last night, going to download the ASCOM drivers today and try that method, I have 
read a lot of good things about it.
I will definitely look up your Polar Home file and do that. 
Thanks for all the help !!

Derrell.

--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


--
Wes, Southport NC
PMC-8, ES ED 127, 10" LX200GPS, Astro-Tech 8" Newt, ETX-90
Polemaster, Orion ST-80 and SAG
Electrical Engineer, Retired


Derrell Oliver
 

Hey Guys !!
Well... This going to show how inexperienced I am with Astrophotography, it seems I was on target with M101 after all, I did use Taros idea of slewing to Mizar before M101... I am used to photographing brighter targets like M42 & M43, M45 and M81 & 82... so I guess I expected to see an Image from a 30 sec exposure !
So I spent some time Friday and Saturday night out under the stars, this is a stack of 278 30 sec exposures @Iso 1600 using a moon and skyglow filter, Canon xsi and my Meade Infinity ST80. Looks like I also found NGC 5474 as well...This mount is really impressing me !!
Thanks to all for the help. Now I need to get better at processing images!!
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Wes Mcdonald
 

Darrell

Nice image.

You go to Mizar and sync first?

Wes


--
Wes, Southport NC
PMC-8, ES ED 127, 10" LX200GPS, Astro-Tech 8" Newt, ETX-90
Polemaster, Orion ST-80 and SAG
Electrical Engineer, Retired


Derrell Oliver
 

Thanks Wes !!
Yes, after doing the 2 star alignment using Capella & Dubhe I went to Mizar centered it in my crosshair eyepiece press sync then put my camera on the scope, opened up APT TOOLS, zoomed in using live view and focused  getting both Mizar A & B nice and sharp then slewed to M101, set my sequence plan and let it rip !!
 I took 150 frames each night, 50 darks & 50 bias frames.
Thanks again.
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Derrell Oliver
 

M51 from Thursday night..
190 30s lights
50 darks
30 bias
30 flats ( first time I’ve shot flats ! )
taken with my trusty Meade ST80
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


bill rowe
 

Derrell:

Very nice.  I'm using a 200mm lens at the moment so your 400mm images are very appealing and the ST80 seems nice and compact.  How is it attached to the mount? Do you have tube rings?

And have you switched to ascom for pointing instead of explorestars?


Derrell Oliver
 

Hi Bill,
I'm using 90mm tube rings and a 8 inch dovetail bar, I should have gotten a longer bar, it is 
still back heavy with the Camera attached.
Thanks..
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Derrell Oliver
 

Hi Bill,
I actually have just downloaded the ES Ascom driver and the PCM Eight configuration manager , going to set it up this weekend so I can
use APT tools to point with and platesolve, I've been using it to control my Camera for a while now, it's a great app.
I'm also waiting for a Guide scope, I have PHD2 already loaded on my computer. 
--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Derrell Oliver
 

Hey Guys,
So I've been busy the past couple of weeks learning a few new tricks.
#1  Pointcraft Plate Solving in APT ( what a game changer !! )
#2  Auto Guiding with PHD2, Im using a Orion 50mm Mini guide scope and my ZWO ASI 120mc-s for right now.
I had trouble finishing the calibration the first time I tried it, it would lose the star, there was a few high thin clouds that 
started moving in right after set I set up, imagine that !!
I did change a few settings... increased the search area to 50, disabled the star mass setting, increased the minimum star HFD to 3.0, Increased the Target SNR to 15.
The second time went very well, I had it guiding on M101 in no time it seemed. I took 50, 60 second exposures, I have not stacked & processed them but the stars look nice and round. I am still working on fine tuning my Polar alignment.
RA RMS = 0.46
DEC RMS = 0.28
TOTAL RMS = 0.54
I attached the Guiding assistant screen shot, so how does this look for my 
first attempt at guiding ?


--
Derrell Oliver

Meade Infinity ST80 with Lunt Solar dual speed crayford focuser.
Meade Polaris 90 with GSO dual speed crayford focuser.
Meade Polaris 130 with ScopeStuff 1.25 crayford focuser, flocked tube and center spotted mirror.
GSO 8x50 RACI finder scope.
ZWO ASI120mc-s, Canon XSi 450d.
iEXOS-100 PMC Eight.
EQ2 Mount with Orion EQ-2M RA Drive.
AZ3 Alt-Azimuth Mount.


Wes Mcdonald
 

Darrell

Glad you got things going.

The PHD guiding assistant seems to give a poor estimate of your polar alignment error unless you let the mount run through one full worm cycle.  So do that test for 600 seconds as close as possible exactly.  Manaul says it does not matter but I and others have seen that it does.

Your guiding numbers are in units of.....pixels I think?  If they were arc seconds it would be fantastic...not sure the mount can do that with the mini guide scope.  Let us know the units.  Guiding under 2 arc secs RMS is routinely possible.

In the end the star quality is the ultimate test for your guiding performance.   

Great moves!

Wes

--
Wes, Southport NC
PMC-8, ES ED 127, 10" LX200GPS, Astro-Tech 8" Newt, ETX-90
Polemaster, Orion ST-80 and SAG
Electrical Engineer, Retired