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Astrophotography done with the iEXOS-2GT. Post your picture #EXOS2 #astrophotography

Jim McKee
 
Edited

It was suggested that the EXOS-2 owners also post successful photos in a single thread.  AP on the EXOS-2 is a path that takes many months to get all the pieces to work together, especially for us beginners, but on a clear night, the EXOS-2  is a very capable mount.   So here is my post from last night on the Eastern Shore of Maryland.  It was very clear with a much reduced amount of haze/city lights.

The below are the result of 15 subs each w/ Darks at 640 ISO and 8 minute exposure times. PHD2 tracked well at RA of 1.1" and DEC of .65".  RA and DEC all had periodic excursions of as much as 2-3 arc-sec, but they all seemed to settle out and tracking was consistant for about 4 hours.  While they all looked like saw-teeth patterns, RMS was satisfactory.
M31, M33, M45








--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. Backyard EOS, StarTools, APT, DSS
Computer:  Dell Latitude E5450, Windows 10

 

Very nice!  

--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

 

Brief clear skies a couple of nights ago, and a long session last night, on the Heart Nebula :-)
EXOS2 PMC-8, D5300 (unmodded), SV 102EDT, Hotech FF, Optolong cLS-CCD filter, DSS and StarTools.
Technique change to aggressive dithering to help manage noise.
 
Heart Nebula / IC 1805, 
10x300s + Flats and Dark Flats (dither every other)
21x600s + Flats and Dark Flats (dither every exposure)
 
4hr, 20min total
 
Just today's first try at processing this.  There's so much going on in the data, that there's more than one way to do it. :-)
 
- Bob
 
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Jim McKee
 

Looks great Bob.  Is your D5300 astro modified? Good pickup on Ha.  I know Nikon/Sony sensors pick up red better than Canon Sensors.  Great roundness on stars
--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. Backyard EOS, StarTools, APT, DSS
Computer:  Dell Latitude E5450, Windows 10

 

Thanks, Jim!
 
Nope, the D5300 is stock.  When I did my Veil exercise / CLS-CCD first light, I got lots of advice on CN about getting modded.  I wouldn't mind, but it ain't so simple (or inexpensive) on this side of the 49th and in CAD$. And then there's my unexpectedly-fussy-about-spacing FF that I don't want to mess up.  I looked at cost and risk, and I'm pretty much ok with leaving well enough alone for this camera.  I'm actually pretty surprised at how well it's doing with Ha.  I know that it's costing me time, but so far this looks manageable. 
 
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Vince White
 

All,

I'm just getting started with astrophotography and thought I would share my second attempt (my first attempt was a frustration in alignment and motivated me to build the RPI4 box).  I built a Raspberry PI 4 box tied to the PMC-Eight via a USB serial cable and it is running INDI + KStars + EKOS, and the built-in scheduler, offline plate solver and alignment tools was a total game changer compared to my first attempt.  Having a small RPI4 box attached to the mount and being able to remotely connect to it via WiFi was also a game changer, compared to being stuck next to the telescope outside.  I'm shooting unguided, South of San Antonio in Bortle 3 skies, where 10-15mph wind gust were limiting my exposures to 60 seconds and even then, I wasn't always getting round stars.  I'm also just feeling my way through the nuances of editing the faint signals found in astrophotography.  Wife and wallet permitting, my next steps are an OAG and ZWO guide camera.

Both of these shots are with the 208mm f/3.9 Newt + 5DmkII: 30x60sec lights, 10x darks, 10x flats, 10x bias @ 1600 ISO



--
Mounts: ES PMC-8 EXOS2-GT
Scopes: BRESSER 208mm f/3.9 Newt + ES HR Coma Corrector, Celestron C90 Mak
Cameras:  Canon 5DmkII, Canon EOSm
Misc: 2" Optolong UHC filter, Raspberry PI 4
Software: INDI + Kstars + EKOS, DeepSkyStacker, GIMP, Lightroom

Wes Mcdonald
 

Looking good Vince!

Do you have experience with an OAG?  These things are hard to use.  Suspect you might be better off with a guide scope.  Certainly able to guide you to the max capabilities of the mount.

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

 

Vince, 
 
Very nice!
 
If you're getting 60s, you're doing better unguided than I was ever able to.  I think your resolution is about 1.6"/pixel, assuming your CC is 1:1 and mine's about 1.3", so very well done!
 
These mounts are basically designed for use visual or guided, and when guided can outperform nicely for the price point.  Whether with OAG or guidescope, guiding is a good thing. 
 
- Bob
 
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Jim McKee
 

Good looking work Vince.   Glad you are exploring INDI and Raspberry PI.   I look forward to hearing how this progresses. 
--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. Backyard EOS, StarTools, APT, DSS
Computer:  Dell Latitude E5450, Windows 10

Vince White
 

Hi Wes.

No, I don't have experience with an OAG or guiding in particular (other than reading way too many Cloudy Nights posts) and I'm not sold either way, however, the engineer in me likes the concept of utilizing the same optical light path when guiding so as to minimize the flex/movement between the guide scope camera and imaging camera.  My newtonian certainly isn't the most robustly constructed telescope around...  Most of what I've read indicates that people usually don't do OAG due to the perceived complexity and increased costs.  I don't mind the increased complexity as long as there is a gain to the total system performance in the end and pricing things out, the cost does seem to be about equal.

What, in your experience with OAG, makes it hard to use?

Regards,
Vince
--
Mounts: ES PMC-8 EXOS2-GT
Scopes: BRESSER 208mm f/3.9 Newt + ES HR Coma Corrector, Celestron C90 Mak
Cameras:  Canon 5DmkII, Canon EOSm
Misc: 2" Optolong UHC filter, Raspberry PI 4
Software: INDI + Kstars + EKOS, DeepSkyStacker, GIMP, Lightroom

Wes Mcdonald
 

Vince:

So here are my thoughts.  No doubt many will have other opinions.  That's fine.  There is no right answer, but methods have their puts and takes.

Flex is something that can come up.  No doubt.  That's a take from guide scopes.  This is addressable however if your mount has the weight capacity to take the extra weight for stiffness.  

OAG steals a bit of light from the light path.  Minor take, for a scope in the 208mm range where photons are plentiful, not a concern.  

OAG has a tiny take-off prism or mirror.  This ends up having a small field of view.  This is where I bit it trying to use it.  But also I couldn't get the damned thing in focus simultaneously with the two cameras.  But I was a neophyte at the time.  Also a good OAG has the focus ring for the guide camera, so it ought to be ok.  Finally, the OAG mirror is adjustable so it looks all around.  This ought not to matter, but I couldn't really deal well with it.  These are the Takes I experienced with the OAG.  Again, I was a neophyte and I have not bothered to go back.  And I had an Orion OAG which is sort of inexpensive.  No doubt if you pay enough for one some of the usability issues I had may vanish.

Using a guide scope is so easy.  And on your big scope you could put an Orion ST80.  That little scope is nice, and man does it gather light for guiding, with a large field of view.  Of course you have to work the numbers on your guide camera pixel scale relative to your main camera pixel scale.  I have a document that will help you choose the FL of your guide scope given your imaging scope and cameras.  It is mostly ok.  Still mulling a few things.

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

 

Vince,
 
What Wes said.  Below is a long and interesting thread from CN by someone who ran a pretty exhaustive test of OAG vs Guidescope.  I've looked at OAG too, and came to the conclusion that it was a solution to problems that so far, I've been spared. :-))  
 
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Vince White
 

Wes,

Thanks for the detailed reply and the guide camera paper. It'll take me a couple of months of over-analyzing things with too many spreadsheets before I'll finally decide a path forward and buy guiding hardware.  That said, I have read several less than favorable reviews of Orion branded OAGs, so it does sound like many of your usability issues are due to the Orion design.

Regards,
Vince
--
Mounts: ES PMC-8 EXOS2-GT
Scopes: BRESSER 208mm f/3.9 Newt + ES HR Coma Corrector, Celestron C90 Mak
Cameras:  Canon 5DmkII, Canon EOSm
Misc: 2" Optolong UHC filter, Raspberry PI 4
Software: INDI + Kstars + EKOS, DeepSkyStacker, GIMP, Lightroom

Jim McKee
 

3/4 moon last night.  In spite of that I wanted to test new CLS CCD filter and try using NINA software based on what I have seen from others on the forum.   I think haze was not bad, so filter test was probably inconclusive.  Test of NINA was very satisfying.  I am switching over from APT for two big reasons, first is excellent autofocus process with this software and second is being able to show PHD2 graph on same screen with imaging and sequencing screens.

 

The EXOS-2 GT continues to work very, very well using long exposures and low ISO’s on the DSLR.  On average last night, these photos were shot at 240 sec and 800ISO or less.   PHD2 guiding on the mount was approx. RA 1 arcsec RMS and DEC .6 arcsec RMS.  I was able to shoot for about 5 hours continuous with no PHD2 recalibration.  I just moved from one target to the next.

 

Of note, I have found the home position for the EXOS-2GT and with good PA, targets are always in frame with the first goto.  Minor platesolving is then used to center the target.

 

Here are the results of last night.  I am still working on finding processing sweet spot.  No darks were taken due to end of evening technical issues.

 

Horsehead and Flame nebulas

 

 

M42

 

 

Veil (this was a tough one.  I will reattempt during new moon period and see if I get better contrast.   This is approx. 30 frames.)

 

 


--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. Backyard EOS, StarTools, APT, DSS
Computer:  Dell Latitude E5450, Windows 10

 

Jim,
 
Very nice, and so much texture in that Flame shot... :-)
The Veil is tough. I was fortunate to have no moon when I shot mine - you'll get more when the Moon goes down.  
 
- Bob
 
 
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

myron_wasiuta
 

Gorgeous images Jim!
Myron


On Sep 26, 2019, at 10:18 PM, Jim McKee <mckeejh@...> wrote:

[Edited Message Follows]

It was suggested that the EXOS-2 owners also post successful photos in a single thread.  AP on the EXOS-2 is a path that takes many months to get all the pieces to work together, especially for us beginners, but on a clear night, the EXOS-2  is a very capable mount.   So here is my post from last night on the Eastern Shore of Maryland.  It was very clear with a much reduced amount of haze/city lights.

The below are the result of 15 subs each w/ Darks at 640 ISO and 8 minute exposure times. PHD2 tracked well at RA of 1.1" and DEC of .65".  RA and DEC all had periodic excursions of as much as 2-3 arc-sec, but they all seemed to settle out and tracking was consistant for about 4 hours.  While they all looked like saw-teeth patterns, RMS was satisfactory.
M31, M33, M45

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--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. Backyard EOS, StarTools, APT, DSS
Computer:  Dell Latitude E5450, Windows 10

Jim McKee
 

I am still in research mode regarding guiding.  I don't know if seeing was part of the problem.
Tough night.  DEC was all over the place so I turned off DEC guiding.  DEC guiding would be nice for a about 2 minutes, then shoot north 3 arcsec, then stabilized, guided well for 2-3 minutes then shoot south to 3 arcsec.  This just repeated from 9:30pm to 12:30am.  I finally turned off DEC guiding and DEC stayed steady for next 2.5 hours at RMS of no more than 1 arc sec.   Shot 22x4 min of M81/M82.   Photo might be better focused if guiding was lower, but I am happy with the results after trying unsuccessfully to adjust DEC guiding.
 
Here is a processed image on Astrobin. I am still working out how to make the arms of the galaxy more prominent.
--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   EOS 60D Asto Modified
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. NINA,  APT, DSS, PixInsight, Photoshop CC
Computer:  Dell Latitude E5450, Windows 10

Mark Christensen
 

Very respectable shot.

Your DEC puzzle is probably caused by backlash and the fact that you were very precisely aligned on the pole. Maybe too precisely.

Sounds counter-intuitive but having very precise polar alignment means there is virtually no (and it is also a function of the part of the sky you are looking in relative to the error that is there) DEC drift. Drift is usually systematic - it is constant during the exposure (but can change with orientation over time - see Mike Covington's books).

Having a small amount of systematic DEC drift means guiding corrections will always be in one direction and if the scope is slightly miss-balanced (similar to the "heavy east rule" for RA) then the DEC gear is always in contact at the same side of the worm wheel and hence never reverses so backlash never appears once it is worked out during the initial (a few minutes) time in which the guiding stabilizes. I see this all the time with my mounts (G11 and EXOS-2GT).

If there is no systematic DEC drift then you're at the mercy of the atmosphere, which can cause the DEC error to go in either direction and then backlash will be a problem. So that is probably why it worked better with DEC guiding disabled.

Trying to remove backlash by tightening up the gears is usually overdone, which then produces binding. With mounts of this class better to figure out how to avoid it in the first place, either by turning off DEC guiding (if your polar alignment is very good) or by only allowing DEC guiding (an option in PhD and PhD2) in only one direction (North or South). I usually have to do the latter since I rarely can see the pole in my backyard.

Mark Christensen

Jim McKee
 

Thanks Mark,

 

Sharpcap has given me great PA’s within 20 arcsec.    I am going to put a checklist together and see if I can isolate the issues to include the idea of imprecise PA.

 

I got out tonight at 7:30 and made the following adjustments to my configuration of PHD2 before doing some test guiding and shooting:

 

1)   Turned off Dither in the shooting sequence of NINA.

2)  Reset guiding parameters to default values.

3) Set DEC compensation to “on” (Check box checked) based on PHD2 user guide (quoted below)


 "Use Declination Compensation' - if PHD2 can get pointing information from the mount via an ASCOM connection ('Mount' or 'Aux'), it will automatically adjust the RA guide rate based on the current declination.  This box should normally be left checked except in unusual cases.  For example, SiTech mount controllers may apply a compensation automatically, in which case the box should be left un-checked.  Don't confuse this option with 'Declination backlash compensation', which is an entirely different feature.

 

4) Set Dither to Spiral Mode  based on PHD2 user guide (quoted below)

 

'Spiral mode' - tells PHD2 to dither with fixed-size amounts in a clockwise spiral pattern.  This can be a good choice when the imaging camera has significant fixed-pattern noise or the mount has a troublesome amount of Dec backlash.”

 

----------------------------

 

Again, I had great PA before I started (I hadn't seen your note yet)

I then shot M33  (3 lights of 480sec) with no dither.  Guiding was near perfect.   RA varied between 1.2 and .8 Arcsec.  DEC varied between .8 and .6 arcsec.  There were no excursions in DEC for the entire 18 minutes.

 

I turned off DEC Compensation and started guiding again and didn’t have any problems for 10 minutes,  So that doesn’t seem to be the issue.

 

 Even as clouds started to close in, guiding stayed nicely on track until the star SNR dropped below 12db and the star then disappeared.

 

I am disappointed I got clouded in at9pm, but i will walk through the following items and see if I can establish cause/effect next time out.

 

Using tonight’s settings as a starting point:

1)   Turn on dither

2)    Set Polar Alignment “off perfect” by 2 arcsec ]

3)   Set a back-heavy DEC balance

4)    Set DEC guiding to reverse on meridian flip (Jerry’s recommendation ) and guide on each side of meridian

 

 


--
Scope:        Orion EON 115mm APO
Mounts
:      ES EXOS2-GT w/ PMC-8
Cameras:   Canon 6D Astro Mod, Canon 7D2, 1D Mk 2, EOS 60D Asto Modified
Lens:
          Canon EF 100-400mm f/4.5-5.6L IS II
Misc:          TELRAD, ZWO ASI120MM Guide Camera, Astromania 60mm Guidescope, Senso Sesto Focus Motor
Software:   EXPLORESTARS IOS & WIN, Stellarium. NINA,  APT, DSS, PixInsight, Photoshop CC
Computer:  Dell Latitude E5450, Windows 10

Vince White
 

We had some clear skies recently here in Houston and I thought I would share an experiment I did shooting in my backyard with awful Bortle 9 skies.  I was honestly surprised this much detail can be resolved in basically white skies.  This did take a long time to process all ~1000 photos and fiddling in PixInsight.

M31, 800x13sec lights, 30x darks, 30x flats, 100x bias @ ISO 800, no UHC filter


PS, my guiding setup should be complete this weekend, so I should hopefully have some further experiences to share soon.
--
Mounts: ES PMC-8 EXOS2-GT
Scopes: BRESSER 208mm f/3.9 Newt + ES HR Coma Corrector, Celestron C90 Mak
Cameras:  Canon 5DmkII, Canon EOSm
Misc: 2" Optolong UHC filter, Raspberry PI 4
Software: INDI + Kstars + EKOS, DeepSkyStacker, GIMP, Lightroom