Very Amateur Astronomy

After spending Saturday night on NGC2403 we had another clear night on Sunday. I decided to make use of this weird good fortune and take another picture using the William Optics ZS66. Now I didn’t want to unrack the scopes, but I did want to guide so I made the decision to guide with the 250mm reflector, I figured I could use the focal reducer to give a wider field of view, but unfortunately could not get it to focus. No worries though, once pointed at the Pleiades guide stars were very easy to find.

It functioned pretty well as a guider, not that the field of view from the ZS66 makes it very critical. My major problem for the evening was dew, which the ZS66 dew shield could not hold off for long. Still it’s a reasonable result and I’m even happy with the processing. I also had a minor problem with the focuser on the ZS66 not coping well with the weight of the camera and sliding out. Locking it down caused the focus to shift. I ended up having to lock it down slightly in focus then slide it out carefully using my thumb as a lever to get focus. It’s a pain and I will probably take out an evening to dismantle the focuser assembly to see if it can be improved.

Imaging Equipment

• William Optics ZS66SD Refractor
• Wlliam Optics MkII Field Flattener
• Canon EOS 1000D (modified)
• Astronomic CLS CCD Filter

Guiding and Mount

• Custom Orion Optics 250mm Reflector
• LX Modified Philips SPC900NC Webcam
• IR/UV Cut Filter
• Celestron CGEM Mount

Exposures

• 31 x 6 minutes
• 21 x bias
• 21 x dark
• 21 x flat

The images were calibrated, aligned, stacked and processed in Pixinsight.

NGC-2403 is an intermediate spiral galaxy in the constellation Camelopardalis, and is apparently much tougher to image from my light polluted back garden than I expected it to be. It is however the first image taken with my newly rebuilt telecope, and that at least is a success. It was also a relief to reliable take 8 minute exposures and have the guiding mostly work as it should do. Even the meridian flip went smoothly.

The image itself however is not quite as good as I was hoping for, the out lying areas are lost, though you can just about see the spiral arms which is good. I’ll post more details on exposures numbers later on.

Once again clear skies coincided with full moon so deep sky imaging was not possible. Instead I took another go at some planetary and lunar instead as it would be wrong to waste cloudless evenings.

The first is a full frame lunar image taken with the Canon 1000D at prime focus. I neglected to remove the CLS CCD filter and had issues with getting the colour right, so instead I opted to make it grey scale. This is a stacked image of 100 frames, I was very happy to find out that Pixinsight’s automatic star align tool does an excellent job with lunar images, picking up the bright features as alignment points.

The second image is an animated gif created from several Jupiter images taken over 15 minutes showing the moon Io moving across the face of the planet.

(click to see the animation)

The gif is a bit over optimised and thus the quality suffers, but as a proof of concept, and my first ever animated image I’m quite happy with it!

Here is my final image for 103p Hartley from the stack taken on Wednesday the 6th of October whilst Hartley passed near to Cassiopeia. I made this version by following the example of poster Yuriy Toropin on the Pixinsight forum. I was intrigued as to how he managed to get a good image of the comet combined onto a nicely processed star field as no combination of integration trickery was doing the trick for me. The answer was a return to photoshop and the use of layers and layer masks. A handy technique which I will be sure to remember!

I captured some 60 2 minute exposures of 103P Hartley last weekend in the hope of getting something decent out of them image wise. So far the comet is not quire reaching the initial brightness estimates and currently resolves as a bright blob but shows no spectacular tail.

This is the comet on it’s own, I processed each image as normal, performed a star align on the stack to remove any rotation or distortion, then manually aligned each image to the comet itself before using sigma clipped integration method to stack the comet image an remove the star trails.

You can see a slight hint of a tail pointing towards 4.30 o’clock.

In the second image I attempted to combine my star background image with stacked comet image. The normally aligned images with inergrated again using sigma clipping to remove the comet, leaving behind a blob of uneven illumination where it should be. Then I created a new intergration of my star field and comet together.

Unfortunately this didn’t really work that well, the combination of the star field and comet images would be better performed by using layers in photoshop.

I’ll need some more attempts at this, and perhaps another go at capturing better data if the weather allows.

We have a photography club at work and while I don’t enter pictures into the monthly competitions as I don’t do much ‘normal’ photography I do keep an eye on what they are up to. Recently they were asked to do a competition for photographs for the company calender on the theme ‘technical magic’, as it turns out I was asked if I wouldn’t mind having one of my astro photos included.

The competition organisers had a look through the images on my flickr and asked if they could use one of my Orion Nebula attempts from last year. Now M42 is always a crowd pleaser, but I don’t think for a minute that I had done it justice in either capture or processing at the time, the guiding was poor, I didn’t have the CLS CCD filter and from what I can tell they were calibrated and stacked in Deep Sky Stacker, which though I may have found excellent for getting started and especially as a free program I don’t think it’s up to the current standards of Pixinsight.

Looking at the images now I can see that they were captured during a period of overly bright moon light, there is some unfortunate clipping and quite a bit of noise in the background, also with out shorter captures the trapezium region in the center is completely blown out. So my answer was, yes you can use that image, but can I have another go at getting a better picture from the data?

So using the same original data I had another go, doing all image calibration, integration and processing in Pix. Unfortunately I only had the one night to get it done, so though improved it could still be better.

The detail has been kept sharper and noise control was much easier, unfortunately the trapezium is still overly bright, something that could be fixed using shorted exposures and HDR composition next time I image this object. Colour is improved and feels more natural. I didn’t use HDR wavelets this time round, which might make things better.

I’m happier with it anyway, but looking forward to another attempt over the winter to fix the various issues, perhaps a wide field with the ZS66 as well.

I was recently offered a 4x Astro Engineering Imagemate barlow by a freind at BAS who had ended up with two. I’d not explored planetary imaging since my initial attempt lasts year proved that longer focal length was going to be a requirement, but now armed with a decent barlow I have been able to have another go.

The results unfortunately have not been all that I had hoped, the first night offered very poor seeing and I won’t show any of my results. The next night out certainly showed improved seeing, however I was still having a lot of issues getting focus on the planet. This may be down to poor collimation.

Here are the results I achieved though, each image was taken with a Philips SPC900NC webcam on my 250mm F4.8 reflector. Around 1000 frames per image stacked and processed in Registax.

Early in the evening, Jupiter has just come into view form the shed though it right in line with the evil lamp post. You can see the red spot, though thats about the only good news in this attempt

Second try around an hour later and Jupiter is higher and the seeing is improved, I’m still playing with the camera settings trying to find out what works.

Another 20 minutes later.

Signs of improvement and I have some more videos from another night which I think will be better thanks to more accurate collimation of the scope. I’ll post those once I have processed them.

I took this image the night before the Iris images posted below using my William Optics ZS66SD, however in processing I was unable to achieve a satisfactory result. However after the improvements shown to the close up Iris image I though I’d have another go at it. This is 32 x 460 second exposures, still a bit noisey but I’m quite pleased with the end result.

I sat down last night with John Murphy to work out a presentation on Pixinsight for the next BAS practical meeting. As my plan is to run through a demonstration of image post processing I decided to use my Iris image and also to take the opportunity to get a lesson myself whilst I was at it. The result is below and I think it shows obvious improvement in many ways, not least in the appearance of my missing dust clouds.

This naturally means I’m going to need to have another go at the processing on all my recent images.

It’s been a while since my last update, after the rush of objects imaged in Cygnus we got hit by apparently never ending cloudy skies, plus a week on holiday. All of which resulted in me getting nothing down. However I’m back now and with a nice run of clear skies towards the end of last week coinciding with a waning moon.

My target of choice was the Iris nebula in Cepheus and the original plan was to continue with widefield imaging to capture the dust clouds which surround this object, unfortunately when I had finished and stacked my 32 images there was no sign of those structures to be seen. I guess a combination of my cameras lack of sensitivity combined with a half moon on that night ruined that plan.

With another couple of clear night predicted I went back to the 250mm reflector for another go and the nebula itself, I have had this object on my ‘to image’ list for so long that I wasn’t going to give up. Here is the result :

Imaging Equipment

• Orion Optics Europa 250mm Reflector
• Baader MPCC
• Canon EOS 1000D (unmodified)
• Astronomic CLS CCD Filter

Guiding and Mount

• Vixen A70LF Refractor
• Modified Philips SPC900NC Webcam
• IR/UV Cut Filter
• 0.6x Focal Reducer
• Celestron CGEM Mount

Exposures

• 42 x 10 minutes
• 21 x bias
• 11 x dark
• 21 x flat

The images were calibrated and debayered in Iris then aligned, stacked and processed in Pixinsight.