Thursday, July 13, 2017

Astrophotography: Melbourne, Australia, My Back Yard. Meade ETX125 Skywatcher EQ5 Mount


Having "BlownUp" my ETX125's fork mount meant that it has sat in the corner for far too long. It's a nice scope and deserves to be used, time to buy an Equatorial mount and start doing just that.
After much deliberation I decide on an EQ5 with single axis (RA) motor drive on a steel tripod.

I had already "De-Forked" my little ETX, so it was now ready for some "Scope Rings"
I ended using a generic dovetail as the main mounting, this needed some new holes to be drilled and the holes countersunk.
You can also see in this picture that I've mounted an "Arca Swiss" type camera mount to the top dovetail, this will facilitate some wide field photography.

The scope with the mounting hardware weighs in at 4.7Kg, well below the mounts max load rating of 9Kg.

Here is what it looks like.




I've added an extra accessory tray.





These are the closest fitting "Tube Rings" I could get, you can see the packing required to clamp the tube.
I've made a little laser pointer holder from some PVC pipe, I've also modded this to run from my regulated supply. It gets connected only when needed so the cable is out of the way. It "draws" 330 milliamp, so batteries wouldn't last long.


Using a cut down generic dovetail allows me to balance the scope. This can't be done with the supplied mounting dovetail, as the position is fixed, and I can't slide the tube forward any more than it is.






This picture shows the re-positioned finder dovetail.
I machined some brass and aluminium to make a double holder. The laser and Red Dot make a great combo.
Currently I have to remove the finders to do any wide field work, like most things I do, this may change...... and already has.














You can see the latest camera adapter here. It's made from a Meade Diagonal some PVC
pipe and an "M42 to Fuji X" adapter.


If you look closely at the focus knob you will notice a simple improvement, a couple of
 "o-rings" wrapped around it makes it much easier to adjust.




The first picture here was taken the night I put it together.
 Not bad and quite inspiring. 
The first three images have been cropped
slightly to remove some "vignetting" in each corner caused by the 1.25" tube on the original camera adapter.



ETA Carina and Nebular.

15sec. 25600asa. f15. Stack of 11 jpg images.
Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Melbourne Australia 2-7-2017
 Close Polar Alignment.(not close enough)

"The Jewel Box"  "Kappa Crucis Cluster" or NGC 4755
Scope: Meade ETX125. 
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
 1900mm. 10 sec. 6400asa Stack of 5 "'sooc" jpegs
 Rough Polar Alignment


Omega Centauri. NGC 5139  
15800 Light Years from Earth.
 Diameter approx 150 Light years 
12-7-2017 
Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
 6.5sec, 12800asa, stack of 7 pics








Moon
 ETX125 Fuji XT1 At Prime Focus. 
Camera now mounted on rear photo port
using a home made adapter.
Omega Centauri is a "Globular Cluster"

approx 150 light years away
14-8-2017

Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
 6.5sec, 25600asa, stack of 18 pics
Un-cropped 




Same details as the next image, but on the 27th
Eta Carina and Nebulae.
 No cropping needed as there is no vignetting through the rear port
with my new adapter.
26-2-2018
Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Stack of 23 x 30 sec asa 25000 "subs"



Orion Nebular

4th Jan 2018
Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Stack of Twenty 13sec asa 25600 exposures
Stacked on Mac using "Hugin" tools
Processed in "GIMP"




M42 and "Running Man Nebula" 4th & 9th Jan 2018

Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Stack of Twenty 13sec asa 25600 exposures
Stacked on Mac using "Hugin" tools
Processed in "GIMP"
Composite of two Pictures.




Alnitak & Horse Head Nebular


Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Stack of 12, 25sec asa 25600 exposures
Stacked on Mac using "Hugin" tools
Processed in "GIMP"



Alnitak and Flame Nebular

Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive



Blood Moon 31-1-2018

Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Single jpg ASA1600 Exp 1.5 sec


Tarantular Nebular. LMC

160,000 light years away
26-2-2018
Scope: Meade ETX 125
Imager: Fuji XT1 at Prime Focus
Mount: SkyWatcher EQ5 RA motor Drive
Stack of 16, 25sec asa 25600 exposures
Stacked on Mac using "Hugin" tools
Processed in "GIMP"




Friday, February 24, 2017

Astrophotography: Melbourne, Australia, My Back Yard




Light Pollution limits what you can do in the city, but it's worth having a go.
It's been clear most nights in Melbourne recently, time to do just that.

The first pic "M42 Nebular" in "Orion" is a "stack" of just 4 shots.
I had no real plan, so the exposure time for each shot varies from 8 sec to 20 sec, my stacking technique ignores exposure time, so no problem there.

I used my recently modified and untested (I made it smaller) "Sector Drive" mount, which I can now say works quite well.

Taken with a fuji XT1 at 3200asa through a Pentax M 135mm f3.5 lens at f4.
Looking at the bright star toward the top of the picture tells us this lens is "stopped down" and has an 8 blade iris.

I've been out most nights trying different targets and different lenses, the following images are the result.



Orion Nebula M42 Fuji XT1 Pentax 135mm f3.5 at f4, Cropped

Takumar 200mm f5.6 6400asa 8 sec single image.
 M42 going down over next doors nectarine tree.
 Clouds began rolling in, time to come inside.


"Eta Carinae Nebula"and the"Southern Pleiades" 
Pentax M 135mm 10sec 10 stack f4 Fuji XT1.


I've just received and repaired a Carl Zeiss Jena 135mm f3.5 M42 lens.
This is a great lens and I intend to do a detailed review soon. For the moment, here is a quickly put together Astro picture from last night. 

ETA Carinae Nebula Carl Zeiss Jena 135mm at f4.8 6400asa 10sec stack of 9 Fuji XT1.Cropped
8th March 2017 10:00pm


As you can see below, a longer lens (Tak 200mm) and a tighter crop really does help.
All my images are "stacked" on a Mac and post processed on the Mac using "Gimp" or "Rawtherapee" both free and available for Mac.

The aligning and stacking is done using some "command line" tools included with the application "Hugin" Panorama Creator.




"Eta Carinae" 200mm Takumar at f5.6 6400 asa 8 sec exposure stack of 11images, Cropped. Fuji Xt1

"ETA Carina Nebular" 300mm Takumar @f4.8 6400asa 15sec. stack of 11 shots Cropped.
Post processed in "RawTherappee"

Sat 15th April 2017 10:23pm




"Omega Centauri"  NGC 5139 .Takumar 200mm f5.6 3sec 12800asa stack of 5 images,
 cropped. This Globular Cluster consists of about 10,000,000 stars. 
I's quite hard to find from our back yard, but perseverance paid off.



"Jewel Box" Star Cluster. This is very close to the Southern Cross and not too hard to find.
Takumar 200mm f 5.6 lens. 6.5sec, 6400 asa. Stack of 5 images, heavily cropped. Fuji XT1





This Is a wide angle view South from our back yard.
 Clearly light pollution is a big problem anywhere low in the sky.
I was looking for the "Large Magallenic Cloud" and as luck would have it I found it.
It's the light area next to the tree, amongst the orange glow of light pollution.

 I'm pretty happy I found it.
Fujinon XF18mm f2.0. 4 secs 2500asa


Following on from the previous image.
 I pointed a 50mm lens at it, and with a lot of post processing managed
 to dig it out of the murk, a bit. 
"Large Magallenic Cloud" 
160,000 light years away
This image was captured the following night.
 Here I used my "CZJ" 135mm lens at f5.6.
6400asa 8 secs.
This image may be as good as it gets from the Back Yard. 

This was taken about an hour earlier than the previous ones, so it was
 a little higher in the sky.
"Large Magallenic Cloud"