Jupiter 2nd August **UPDATED**

[markt]

I had alot of fun observing Jupiter last night:  it was my first telescopic observation of it of the year and also my first telescopic observation of it  using my C8 which I bought earlier in the year.

I spent some time properly polar aligning first and it paid off, during about 3-4 odd hours of observation the planet barely shifted in the fov.  Being an eager beaver I had no time to allow the C8 to cool down so just popped my 40mm ep in giving me 50x.  The disk and clouds were easily visible as was the moon system, however the shimmering image as a result of tube currents was plain to see.  Time to put the kettle on at this point to give the scope time to cool and I returned outside 1/2 hour later.  The image had really settled so I tried the 20mm type 2 nagler - I was blown away!  In the moments of good seing the view was fantastic.  Being greedy for magnification the 13mm ethos went in, but this was way too high for the seeing conditions and the view was no good. 

I was keen to try out my Pentax 6.5-19.5mm zoom eyepiece.  I bought this for using with my Coronado SM40 as zooming allowed me to really get the best image the seeing conditions of a particular day would allow.  I was taken back with the view, at 19.5mm the image was essentially the same scale as with the 20mm nagler, but I felt the image with the nagler was 'yellower' than with the pentax, and when the seeing allowed the pentax just allowed me the edge in detail.  Being a zoom I was able to tease the magnification up to the optimum point.  I was really enjoying the view!

I then decided to have a shot at imaging using my DMK31 camera.  I got this shot >>>



About a 1000 subframes from 1400 stacked in Registax5.  You can just see Ganymede on the right of the frame, and Europa is on the left.  I'm quite pleased given this is my pretty much first attempt at a planetary image.  Though I have to say post processing for Jupiter is totally different than post processing for Hydrogen Alpha!  If anyone has any tips I'd really appreciate them please - I know people use a filter when doing monochrome images of the moon and planets like this, but which is the best one to get?

I went back to visual after this, comaparing the nagler and the pentax, when I noticed a 'milkiness' to the image and loss of contrast.  A quick check revealed I was dewing up - in my haste to observe i'd forgotten to turn the dew heaters on.  A quick blast on full power cleared it, but for a good 20mins destroyed my seeing.  Once the pre-dew was cleared the heaters went back to their normal levels and the better seeing returned.

I had seen all night Ganymede was gradually getting closer and closer to Jupiter, then all of a sudden in between switching between eyepieces Ganymede had disappeared!  I realised it had passed into eclipse!

About 3.30am and weary I packed up and returned inside but well and truly pleased with the nights observations! 

[Paul]

Sounds like a good night Mark! Clouded out here I'm afraid though I'm looking forward to the opportunity to image Jupiter - I haven't done so for a few years as it has been so low in the sky. Nice image given the atmosphere it was shot through. One tip I will pass on - with Jupiter more images is not necessarily better as the rotation of the planet is such that detail can be lost after just a couple of minutes.

[rjgjr]

Good account of what seems to have been a great night of viewing Mark. Got in some viewing of Jupiter about a week ago on my Astronomy Club's 10", can never get enough of it! Thanks for the report!!

[Carl O Beirnes]

Hi Mark,
Very nice report.

Welcome to our world of planetary imaging.Well done on your first image Jupiter is a great planet to look at and image. Here is a few things the help me a long the way.

First thing to do is if It's going to be clear out leave your OTA outside to cool to ambient temperature for 1 OR 2 hours

Next thing to do is check your collimation first through the eyepiece and then with the webcam. These links should help
www.astro-tom.com/telescopes/collimation.htm
www.astrosurf.com/legault/collim.html

Next thing to do is getting your focus this link should help http://dougroberts.co.uk/astronomy/webcam-astrophotography

If you have a Barlow 2or3 use them when the seeing allows you to. When imaging Jupiter your camera settings should be around 60percent GAIN and less on the shutter speed. Why you might say? if you don't use high Gain your image will be all grainy when you are finished processing it in registax. When processing your image DON'T use the optimizer because you will have vertical lines running through it.


Have a read through this www.astronomie.be/Registax/RegiStax4UserManual_Revision1.pdf . When the seeing is steady there is no need to use the optimizer. After you Align the image Press Limit now see where the options are on the top, click show stackgraph. On the stackgraph you will see one red line witch is the quality and a green witch is the alignment difference. Bring the line down to cut off any spikes. Then move the slider across to adjust the quality cut off point. Now PRESS stack, Once stacking is complete press Wavelet button adjust image to your liking Then press the DO ALL button.save image and head to PhotoShop.

Hope this helps. No one said it was going to be easy. Welcome to the world of planetary imaging.

Keep looking up,

Carl O'Beirnes,
Balbriggan Observatory (MPC #J09)
www.webtreatz.com

[markt]

Thanks for all the kind words guys! 

Some very useful pointers there Carl:  The OTA should always be at ambient temperature before observing, my exuberance and excitement on this occasion got the better of me!  They are fascinating articles on collimation.  I've had the C8 for quite some months now and have never gave collimation a second thought - I got out my Cheshire eyepiece earlier on this morning a gave it the once over, all is well there, but at the level needed for fine planetary details this is only a crude collimation at best.  I read on one of my buddies blog sites last night how he was unhappy with the jupiter images he was getting from his C9.25 and tried fine collimation - lets just say he now swears by a 'fine collimation' every time he observes.  I've always been hesitant about messing with the collimation of my C8, which, tbh, I don't know why, as i've successfully recollimated my refractor with a noticeable image improvement before, however now i'm going to give 'fine collimation' a go on the next clear night i'm out observing.  Hopefully this will be in a day or 2's time as the weather from the west moves through and fingers crossed we get some better skies.

Thanks again, Mark 

[markt]

When I was on my hollibops in Anglesey last week in between watching out for Perseids there was a healthy dose of Jupiter on the menu.

Taking into account what Carl said about collimation I decided to take heed and carry out the procedures in the links he posted.  While I thought my collimation was ok, when I started looking at the Airy disk pattern at high magnification you'll probably not be surprised to hear alignment was slightly out.  I have to confess my initial thoughts were that it wouldn't make that much of an improvement - oh how wrong I was when I turned my freshly collimated C8 to Jupiter:  A whole new level of detail was visible un the cloud belts - I was mesmerised!!! 

I decided to have another shot at imaging it:  I hope you'll agree it's quite an improvement on my first attempt, and given this is only my second attempt at planetary imaging, ever, i'm pretty pleased too 



You can see a couple of moons visible too.

Hope you like it! 

Mark 

[rjgjr]

Great image Mark, it sounds and looks like you have many more succesful nights of observing and imaging ahead of you. Look forward to seeing more of Jupiter and beyond!!