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My first light with 170 year old refractor, (Doing it old style).


philj

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After restoring the Smiths of London 3.25" F16 refractor and getting it up an running on the hardwood field tripod the weather got in the way and I was only able to do a quick star test in the few weeks since. However when the forecast for last saturday showed clear skies, I was up for giving the scope a proper test.

 

So I set off through driving wind and rain up to the EMS dark site (Tannenbaum Campsite Belper).

Managed to get up there though I was wondering if it would be a wasted journey but  wow it was clear when I got up there.

 

I took the 3.25" Smith mainly to to test on Jupiter and Saturn but also have a wander around the skies the old fashioned way and I had a pleasant couple of hours testing.

Belper dark site may not be darker than my garden but the horizons are excellent, much better than my tree blocked garden.

Because the scope is big and there was quite a strong cold wind I set the scope up in the lee of my van for a bit of protection but even there the wind was still buffeting the scope highlighting the inherent  instability in this design of pillar mount.

 

The wood tripod I modified gave sterling performance though I was pleased to see but the wobbles were emanating from the brass pillar. I will bodge some tube rings up and fit this scope to my EQ5 next to give it a thorough test but at the moment it was sufficiently useable to check the scope out.

I was using Tak 24mm and TV Delite 18.2mm eyepieces throughout with my 1.25" to RAS adapter and the period prism diagonal that came with the scope which I modified to take 1.25" eyepieces as well. This gave 53 and 70x respectively, wobbly mount and atmospherics meant higher mags were not really useable. I soon found using the prism to be the more comfortable option despite the tripod being at a good height.

 

Planets

As the evening progressed and Jupiter rose higher out of the murk over Nottingham  Jupiter in the both eyepieces was sharp and showing the main belts really, well when the scope wasnt being blown around.

Saturn was a little jewel with the shadow of the rings on the globe evident when conditions allowed.

 

DSO

Now the period narrow field of view finder was making its limitations evident. The apeture is 1" and the FL quite long so it wasnt really much help except to point the scope at a brightish star near the object I wanted to view. So I resorted to the old method of sighting along the very long tube and star hopping to my targets.

 

First off was the Double cluster. A comfortable height and easily found. It showed the two clusters nicely within the Tak 24mm FOV. Image was a little dim due to the aperture and fl but the key members were there and some colour evident in the red/orange stars.  This prompted

 me to have a look at some colourful doubles.

 

Almach. A nice easy split in both eyepieces and showing the colours nicely. Stars in this scope show as nice pin sharp points of light and this gave a pleasant image.

 

Albireo was a strain to find due to its altitude but worth the effort with striking colours.

 

As the scope was pointing high up I went for Epsilon Lyra. After a few misses I found it and was presented with a nice wide split on the 2 main components but the wind and wobbly mount  made trying to split at 70x impossible, ah well next time.

 

Alcor Mizar was a must and all components were easily visible, you could drive a bus through the separation.

 

I then moved on to a couple of globulars. M13 was a nice size at 50x but only the outer stars were resolvable with either eyepiece. M15 was a nice tight globular and showed a bit brighter than M13.

 

M31 was a must, with M32 easily viewed and after a bit of searching I detected a faint M110, but the general view was OK for a 3.25"

 

M57, I found straight away and showed as a nice smoke ring against a dark background.

 

M27 was a struggle to find but I got there in the end and was pleased to see the familiar dumbbell shape easily instead of just a smudge.  

 

M45 with the 24 mm Tak was showing a part of the cluster only and it was a pleasure to wander around the cluster with the blue white stars showing as nice pin points.

 

Similarly I wandered along the Coat Hanger asterism with the 24mm.

 

I was concerned about the scope performance when I tested the optics with a cheshire eyepiece which showed a slight collimation issue which I could not adjust due to the non collimeatable cell. However this dark skies test showed that the scope has promise.

The next test will be with it bolted to a more substantial mount then I can do proper planetary testing with it. I always enjoy being able to get out under a dark sky and do old fashioned manual  astronomy.     

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The scope with Jupiter in the background. The dew shield was robbed from a dead Konus 90mm for the purpose of the test and bodged on with a bit of sticky.

 

 

 

Edited by philj
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Fine report Phil particularly because it is a long focus instrument of considerable  age, the sort of telescope I used to dream about as a kid.

I no longer have Andromeda, but do still have Arcturus the A.E.Luton 41/2" f14, and I really should use it.  

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2 hours ago, JeremyS said:

 

I love the contrast with the ultra modern EPs you used.

Its the only way i test these scopes. The old RAS eyepieces were ok in their day and are nice to look "AT" but not through. They are wanting on exit pupil, eyerelief and FOV mostly, so using a nice modern quality eyepiece is more comfortable and also shows how good or bad the objective is.

Apart from cleaning them and a brief test early on terrestrially I havent touched the brass eyepieces that came with it.

Edited by philj
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