Saturday, January 16, 2016

''Hind'' Newtonian Telescope on 23-rd December 2015

This is the Newtonian telescope built by my friend Tavi aka Erwin  around mirrors made by David Hind from UK.
Specifications  : 
-primary mirror diameter = 158mm 
-primary mirror focus 1240mm
-secondary mirror m.a. = 32 mm
-DIY Dobsonian mount :all the parts ( except optics ) were 
made ,adapted ,adjusted and  assembled by Tavi.




Here we see Tavi at an outreach sponsored by ''Resita TV''  at Resita .
This action happened at the launch  of a TV documentary intitled ''On the footsteps of the first astronomers'' hosted by Marc Francu.


I'm having the honor and pleasure to use and test this telescope for a while.

Here follow some observations made by myself with the ''Hind'' 158mm Newtonian on 23-rd of December 2015.
I used deliberately Galilean oculars on the first test.
Their resolution and contrast on stellar objects is very good and  the sky background is very dark.
The Galilean  oculars are doing justice to the resolving power ,to the definition and penetration capabilities of the telescope.
However this type of ocular is very unfriendly and unforgiving to the user.
(So here is my advice ; ''don't do it at home'' unless you are a perfectionist freak! )
One was a Galilean ocular with a focal length of - 50mm sent by Carol , my colleague from ''60mmtelescopeclub''.
In order to reach the focus , I had to use my Japanese  2 x Barlow lens ,which in this case , become a 3x Barlow lens.
The magnification of this setup was 74 x.
The other ocular used on this test was a Galilean ocular with a focal length of - 9mm providing a magnification of   138 x .
The Galilean - 9 mm ocular is reaching focus.
This ocular was made by my friend Silviu aka zoth.











In a few words : excellent telescope ,very good optics , reliable   mount !

''The Celestial Passion'' by Richard Watson Gilder











Monday, December 14, 2015

TELESCOPE MIRROR BLANKS -END OF YEAR STOCK TAKE

Work-In-Progress mirrors and mirror blanks at the end of 2015.
Upper row ,from left to right :
*143 mm x 11mm thickness,not grinded
*156mm x 14,7mm thkns,fine grinded up to #800 abrasive for F= 1240mm or F/7.9
*160mm x 16mm thkns ,fine grinded up to # 800 abrasive for F = 1200 mm or F /7.5
*317mm x 22 mm thkns ,fine grinded up to # 800 abrasive for F= 1360 mm or F/4.3
Middle row ,left to right :
*91mm x 11 mm thkns ,fine grinded up to #800 abrasive for
 F = 810 mm or F/ 8.9
*72mm x 7mm thkns , fine grinded for F= 690mm or F/ 9.6
*76mm x 14mm thkns ,cast , not grinded
Bottom row ,from left to right :
* 150mm x 18mm thkns , cast , no tool blank
*125mm x 15mm thkns ,fine grinded up to #800 abrasive for
F= 1440 mm or F/11.5
* 182 mm x 18 mm thkns ,rough grinded for F = 1650mm or
F/ 9.17


The 125mm cast blank and tool , fine grinded for a focus of 1440 mm or F / 11.5.

The 150 mm x 18 mm blank.

The pair of 143 mm x 11 mm blanks , untouched.

The 180 mm x 18mm thkns  blank , bought rough grinded for F= 1600 mm from Ioan Zaidel , a famous telescope maker of Romania befor and after   World War II.

The 317 mm x 22 mm mirror blank and tool , ready for polishing at F / 4.3.

The coumpund thickness of  of the 317 mm x 22 mm  mirror blank and 15 mm thkns tool.

Bird  view of  my biggest mirror blank.
Not rated as big by today's standard but not small, tough ...

The 160 mm blanks , the mirror blank is cast.

The 156 mm blanks , cut from a big float glass chunk  ,once part of the ''Ziridava'' show- window.


Thursday, December 3, 2015

Moon Corona on November 23rd 2015

Moon Corona on November 23rd at f= 27.6mm , f/6.5mm, shuter speed 1 s , ISO 80.
The Moon age was 12 days.



Moon Corona ,  November 23rd,  f= 18.7 mm at f/5 , shuter speed 1/1.3 , ISO 80.


Moon Corona ,November 23rd at f=27.6 mm f/6.5 , shuter speed 1/8 s , ISO 400




The Moon as seen by the tiny objective of about 4 mm aperture  of the Nikon Coolpix S3300 camera at f = 110,4mm,  digital zoom ratio 4x , equivalent   aperture f/6.5 ,
shuter speed 1/6 s , ISO 80.


Thursday, November 19, 2015

''LUNAR X'' OBSERVED ON NOVEMBER 18

Wednesday , 18 November 2015 ,from 18:00 to 19:00 UT , I witnessed the phenomenon  ''Lunar X'' or ''Werner X ''.
This is a clar-obscur effect on the Moon.
The light and the shadow  ''...creates the  appearance of a letter ' X ' on the rim of the Blanchinus,La Caille  and Purbach craters'' according to Wikipedia.


My observation of the ''Lunar X'' it just happened.
I was actually experimenting the use of an IOR binocular head adapted for astronomical use on my home-made 125mm F/7 Newtonian reflector.
The exquisite main mirror of this reflector was made by late Gavril Beches of Timisoara, a very gifted and self-taught mirror maker and passionate amateur astronomer.
The binocular head was checked , fixed and colimated by Silviu aka ''zoth''.
The adapter to 1,24'' of the bino head was made by Tavi aka ''Erwin''.
First I enjoyed visually the show.
Next I took the afocal pics with my Coolpix S3300 compact digital camera hand held over the right channel /ocular of the binocular head charged with a magnification of 140x.
I rotated the ocular in the drawer and moved the ''Lunar X'' all across the visual field just  to be sure it is not an optical artifact or an aberration.



Lunar X 18.11.15 reflector 125mm



LunarX November 18

LunarX , afocal , 125mm reflector 140x

LUNAR X

LunarX 18.11.2015


Lunar X in bino head 140 x

To be 100% sure it is a good practice to observe the same phenomenon with different instruments.
 Out of curiosity,  I made observations of the ''LunarX'' also with my ''one foot achromatic'' or my short refractor of 45mm aperture and 300mm focus, in the ST mode.
The magnifications used were 30x / Faworski 10 mm Plossl and 75 x / Kasai 4mm Ortho.
At both magnifications the ''Lunar X '' was very nice and clearly visible.
I took some afocal pics at 30 x.
A star in ''occultation danger'' was noticed to the East.


Lunar X and possible occultation in 45mm x 300 mm refractor ,afocal , 30 x




Lunar X 18.11.15 in 45mm refractor 30x

It was a beautiful and unexpected gift ,thank you Lord !









Monday, November 16, 2015

Messier 2 and Messier 110 in my home-made 125mm Newtonian telescope

Globular cluster Messier 2 in Aquarius ,observed on November 10 with my home-made 125mm Newtonian reflector at the magnification of 144x  obtained with a  Tele Vue '' Radian''  6mm ocular.
The central region equal to half of the diameter seam  uniformly brighter than  the peripheral region.
No internal structure nor individual stars were visible.
The edge seem foggy and with averted vision the aspect of the cluster is granular , showing a tendency to eventually resolve to stars in a  telescope of  bigger aperture.


"M2map" by Roberto Mura - Own work. Licensed under CC BY 3.0 via Commons - https://commons.wikimedia.org/wiki/File:M2map.png#/media/File:M2map.png


An object I presume to be Messier 110 ,a dwarf elliptical galaxy -satellite of the Great Andromeda Galaxy.
As seen at 216x / Kasai 4mm Orthoscopic ocular , in my 125mm reflector on November 10.
In the  35 x visual field of the ''Sirius '' Plossl 25 mm ocular ,this object is visible at PA = 230 to M31.


Sunday, November 15, 2015

Pi-1 + HJ 953 Pegasi and 36 Andromedae double star observations

Pi-1 and HJ 953 in Pegas in the same visual field.
Time :November 10.
Condition : seeing Pickering 6-7 , fog.
Instrument :125mm F/7 Newtonian
Magnification : 144x / Tele Vue Radian 6mm.
Resources: Toshimi Taki&Wehner Double Star Atlas.

36 Andromedae
Time : November 10 and 12.
Conditions: seeing Pickering 3-4 ,passing thin clouds on November 12.
Instrument: 125mm F/7 Newtonian / Dobsonian mount.
Magnifications: 144x / Tele Vue Radian 6mm -touching Airy discs on both occasions.For very brief moments the impression of unstable black space between components on Nov.12.
216x / Kasai 4 mm Orthoscopic ocular ,clear split on Nov. 12 with waving but constantly visible black space between main star and companion.