Equipment for Astronomy

Orion Premium Linear Binoviewer

Posted by Andrew Thornett

My best purchase from the Practical Astronomy Show. These binoviewers differ from other makes in that they do not require any extra in-focus. You never see these on sale….but this one was around £100 off new price! I have tried binoviewers before but the need to use a Barlow lens in order to obtain focus on my Newtonian telescopes has meant that they weren’t very practical. I decent read a review in one of the astronomy magazine about this binoviewers and the reviewer was so impressed he bought one!

I tried it today on my Orion 10″ Dobsonian telescope. In order to get focus, I had to use an extension tube plus my Tele Vue Paracorr – the latter has a long tube and I can pull it out quite a distance to act as an extension tube. All of this suggests that I will easily obtain focus on the night sky.

At the Practical Astronomy Show I purchased a pair of discounted APM ultra flat field 18mm 65 AFOV eyepiece and I already had a pair on Tele Vue Nagler 7mm eyepiece.

The view of the trees at the bottom of the garden was amazing! This the first time I have ever had a proper binocular view through a telescope without any sense of strain on my eyes! Both pairs of eyepiece worked well. I can’t wait to get out under the night sky. Only problem is this could work out really expensive on eyepiece with my having to buy a second one to accompany some of those I already have…..

Andy

  

Always worth having a bag of eyepiece caps so if you see any being sold cheap I recommend you purchase some spares in 1.25 inch and 2 inch varieties for both ends of the eyepiece. Below is my bag – the cheap 18mm eyepiece did not come with caps so good job I had some spare.

The attachments I used to obtain focus – this was opposite of in focus = out focus – as I was focusing on the trees at the bottom of my garden which are closer than infinity.

The Tele Vue Paracorr is one of my best ever purchases – so useful!

Adding Sky Watcher finder scope style mounting shoes to Orion UK 10″ Dobsonian telescope

Posted by Andrew Thornett

My trusty and well used Orion 10″ Dobsonian telescope does not have Sky Watcher style finder scope shoes – a nuisance as I would like to use a finder scope with it and also attach my heated laser finder device which has Sky Watcher style finder bracket.

So today out came the glue gun and I attached two finder shoes to the tube. If the glue gun turns off with time not to be strong enough then I will bolt them on but hopefully this won’t be needed as not much weight on them.

The other advantage of using the glue gun initially is that I can change position of the finder shoes if it turns out they are not in the best place in practice.

Andy

I chose a rather cold day to do this!

OK so in the next picture it looks a mess. However, once the glue has cooled I will then be able to tidy it up and I would rather put a bit more glue on so that my stuff does not fall off the scope, including my bargain from the Practical Astronomy Show – right angled 9×50 finder scope with illuminated eyepiece for only £45, which I bought especially to put on this scope!

 

Purchase from Astrofest – Orion UK eyepiece tray

Posted by Andrew Thornett

I have just installed a great £20 Accessory I purchased at European Astrofest 2019 – an aluminium eyepiece tray to compliment my aluminium Dobsonian mount base on my Orion UK 10″ Dobsonian telescope. Hitherto, I have been putting eyepieces on base below the scope with risk they fall off if I forget they are there and pick up mount to put it away at end of observing session. This new arrangement is much safer! I have drilled extra holes to install at front but there are also already holes available to install it both sides instead so I will see which I prefer in practice.

Andy

See also:

European Astrofest Day 1 – 8/2/2019

Astrofest 2019 Day 2 – 9/2/2019

Video from European Astrofest 8-9 February 2019

Making our own image intensified eyepieces

Posted by Andrew Thornett

Making our own image intensified eyepieces

Andrew & Damian

 

This entry is a copy of an entry made in November 2009.

The commercial versions of these eyepieces cost £1500 ($2000) upwards…….here we describe how we made one for £50 ($80) plus some spare SLR lens/extension tubes lying around the house.

The main differences that we are aware of between the commercial versions and ours are:-

(i) Theirs has a higher resolution – not that we noticed at the eyepiece!

(ii) Ours has more distortion of the field – oh well you can’t have everything!

(iii) Theirs are a lot lighter…no getting away from that – our version requires a sturdy telescope/mount and 2 inch focuser.

What we are less sure of is:-

(i) Any difference in brightness? Possibly but the image intensifier we used is a 3 stage generation 1 intensifier that gives pretty bright images

(ii) Fun level – ours delivers on the fun side

(iii) Both image intensifiers can be used with an SLR lens without the scope – probably the best bit

(iv) Ours gives you the enjoyment and sense of achievement of having made it yourself

(v) Price difference – this is one aspect of ATM where there is still a really big difference in price between the ATM version and the commercial version!

Please note we accept no liability for damage or injury incurred from following our instructions (its just what we did) and we make no guarantee that this will work for you. Please let us know if you find a better way of constructing your eyepiece so we can update this website. You will need to source components – a difference image intensifier should work but you will need to modify the instructions. Plus – please note neither of us have had a chance to compare our version with the commercial versions.

We hope you have great fun making your image intensified eyepiece!

The two files below are both PDF files:

Image-Intensifier-Info-Instructions-Nov-2009

Instructions-making-image-intensified-eyepiece-2009

Andy & Damian

 

Observing Log 2/2/2019 @ 18:45-3/2/2019 @ 03:30. Damian and Andrew. Photos taken through the eyepiece

Posted by Andrew Thornett

All following photos are through the eyepiece, mostly of the Orion Dobsonian telescope used during this session, but a few from the Tek 140 scope. Photos include photos through Explore Scientific or Ethos eyepieces, and through our homemade image intensified eyepiece on the Orion.

All photos were taken using Samsung S7 smartphone hand held next to the eyepiece.

Andy

Hubble Variable Nebula: The following two photos were taken through the image intensified eyepiece on the 10″ Orion Dobsonian Telescope:

M42 Great Orion Nebula: Image intensified eyepiece:

M42 Great Orion Nebula: Explore Scientific 20mm eyepiece on Orion Dobsonian:

Crab Nebula:

 

Double Cluster in Perseus: Image intensifier:

Double Cluster in Perseus: Explore Scientific Eyepiece:

M82 in Ursa Major: Image Intensifier:

M81 in Ursa Major: Image Intensifier:

The Eyes Galaxies at the end of Markarian’s Chain: Image Intensified Eyepiece:

M13 in Hercules: Image Intensifier:

Telescope sale

Posted by Peter Hill

Hi folks,

am having difficulty handling these scopes now so am downsizing and selling these to a good home!!

9.25″ Celestron SCT with StarbrightXLT coatings. Including:

Antares F6.3 focal reducer

Antares 2” tube with twist grip

Celestron 1.25” star diagonal

Celestron 1.25” Visual back.

Celestron 9×50 R.A.C.I. illuminated finderscope.

Feather Touch focusser

JMI electrical focuser attachment for feather touch.

Telrad base

Vixen mounting bar, (has been on Skywatcher HEQ5Pro.)

Extra mounting bar on top.

AstroZap flexiheat Dew shield and controller.

Bahtninov mask.

£700 for tube and accessories.

Skywatcher 200PDS Newtonian Reflector. Includes:

Finderscope

Telrad base

Dew Shield

Skywatcher motor drive, can be easily connected / disconnected

from Dual speed Crayford with turn of allen key.

GSL 35mm extension tube.

Bahtinov mask.

£200 for tube and accessories.

If interested contact me on 01283716285 or see meat RAG on Friday.

Pete Hill

 

 

CCDSPEC Spectrometer/QHYCCD 6 camera – effect of turning on the fan

Posted by Andrew Thornett

When I last used my CCDSPEC spectrometer with its QHYCCD6 camera, I was concerned about the number of apparent hot pixels appearing on the image. OK – it did not matter as the nature of the spectrum meant a few hot pixels were neither here nor there but still I wanted my new kit to work properly!

….Then I noticed that I had not been turning on the fan – so tonight I took pictures of the night sky (without telescope) using Nebulosity – with and without fan turned on the QHYCCD6 camera. The effect of cooling by this method is dramatic for these 30 second exposures as you can see below.

NB The spectrum of the night sky is just visible in the middle of each picture (30 second images).

All images from tonight’s session, including FITS files can be downloaded here:

QHY6 camera on CCDSPEC spectrometer – spectrum images of LRO night sky (30s exposure) without telescope – taken on 13/01/2019

Andy

With fan TURNED OFF:

With fan turned ON – only a couple of hot pixels remain:

Dark frame of fan turned ON:

Eq6 rail mod .

Posted by Nick Cox

Xmas goodie, overcomes the steel adjustment bolt versus Aluminium mount problem. Shouldn’t be much of a problem if folk supported the weight of the mount whilst adjusting the altitude to get polar aligned. However , eventually the adjustment bolt will begin to make its slippable groove into the mount head. Modern Astronomy used to sell a cumbersome and well overengineered fix.

The rail mod is much cheaper at about £130 and very easy to fix. Takes about 15 minutes , including time to gather a 16mm wrench and spanner.

Heres what you get ,

It’s beautifully made and you get a choice of self adhesive side plates. First job is to remove the existing glued on ones.. I ended up using a soldering iron to melt my way through. Make sure that you’ve marked your zero on the alt. Cover. Loosen the 16mm bolt on this side at the same time as loosening the holding bolt the other side. Slacken off the three 2mm Allen grub bolts. 

Then remove the bolts and gently ease the head apart . Note where the plastic spacers and metal one go. Clean everything up. Grease the mod and insert it , best remove the adjustment bolts first. Then insert the bolts , ensure the rear bolt enters the hole on the rail barrel. Put plenty grease here, metal to metal. Ensure everything is secure , the rail stops and fits exactly into the bed of the mount, easy.

This shows how it works,

Slide the base into the head . Grease on the plates will hold them in position . Ensure the adjusting bit of the head is between the barrel and the front adjustment bolt . Replace the main bolt . Tighten to give no movement if you jiggle the head. Tighten up the retaining nut and snug up the three grub bolts. 

Fix the side plates on , I used a couple extra strips of self adhesive tape.

The stock bolts are soft steel to stop over grauching of their action on the mount head . The rail mod moves the altitude delightfully easily . Use the front bolt just as a stop, it doesn’t need to be overtightened.

There’s a rail mod for the Heq5 mount in the pipeline.

Easy and it actually works. Polar alignment does not have to be spot on for visual observing and alignment . Accuracy here does allow the fov to stay still at high magnifications.

Very pleased to recommend this mod. For those with plenty time and resistance to repetition , there’s a guide on YouTube.

Nick.