Testing Orion 10" intelliscope setup..

Date: 1st Nov 2008, Saturday
Observation Time: 6:00pm to 7:30pm (1:00 hrs)
Location: MTRP, CA
Weather: 80% cloudy, Sky was in & out
Instruments: New 10” dob & bunch of new eyepieces.
Buddies: Philip and Jack (MTRP Ranger)

Bought a 10" dob last sunday. Orion XT10 intelliscope. I observed jupiter from home, but this was sort of real first session with the dob to test the whole setup and new eyepieces. GSO40mm supeview, Celestron Xcel 10mm and Celestron E-lux 2" 25mm.

Scope wasn't fully collimated. Still not fully comfortable with optics.. Really need laser collimator.

Weather wasn;t friendly either today. Too much cloudy. I think because of clouds, though transparency was bad, the seeing was excellent. So planetary observation was excellent.

Venus phase (New): Venus was best view ever for me.. This is first time I ever saw phase of Venus. I guess the phase was around 70% waxing. Confirm it. (?? Confirmed from heavens-above). With 10mm xcel eyepiece, 120x showed me the phase clearly and luckily, 2x barlow on it, 240x magnification was still in focus. It was fabulous. Orangish-Red color on top-left (NW) edge of venus, while the bottom-right (SE) edge was lil bit greenish. I remember Jon told me abt colors last time.. but I forgot.. Need to read more (??)

Moon: Moon was fine.. the clarity and shaprness of craters was clearly visible. Didn't spend much time in detailed observation.

Tried Jon's GSO 40mm Superview eyepiece. Though i have cleaned the eyepiece, its inner surface is still really dirty. (??)..

Jupiter: With 25mm eyepiece, 48x, Jupiter bands were visible. With 10mm xcel, 120x, it was pretty sharp image. didn't see any other details.

Compared the eyepiece field of view with the Jon's 9mm expanse eyepiece. With Jupiter's moons I was able to get judgment. Indeed expanse had more field of view..probably 7-10 deg more. but i felt that image contrast in xcel was better than expanse.. Need to confirm (??)

Tested the R&P focuser on Jupiter sharpness. focuser is ill bit tight. After using Crayford, use of R&P is indeed undesirable.. the view shakes lil bit while focusing. Need to loose the focuser lil bit. Still.. focuser did excellent job to get the sharp view. Didn't feel like I am compromising on the view...

Alignment and Object locator testing : Spent some time with the "intelliscope".. Two star alignment.. Pointed to Vega. Wasn't able to get a star 60deg away from Vega.. so pointed to Altair.. warp factor was +1.1.. for first shot not bad.. but still should have done better.. but didn't spend much itme becasue of cloud cover rolling in.

Used the intelliscope, to confirm location of Deneb. It was within +/- 1-2deg error margin.
To locate all other objects, used intelliscope.

Alberio: In 25mm view, though not in center. Image was not that great.. yellow-orangish and white-bluish star pair visible. wasn;t the greatest view.

Double Double: Its a good test for eyes, collimation and eyepiece. Again wasn't the greatest view. I think scope wasn;t fully collimated, so was lil bit hard to see the resolving at 10mm eyepiece, 120x.. It should have been perfect at this magnification. but i got the perfect view, at one particular focus.

Again, R&P focus is lil bit tight to handle.

M57 Ring: Pointed to M57 and then checked intelliscope co-ords. In 9mm eyepiece, 135x not the greatest view. Star at2pm missing.. fuzzy ring was visible, but image wasn't sharp. but in 10mm image was great. Star at 2pm visible. I am not sure if transperency got improved within 2mins or not... but image was bright and ring was indeed better than 9mm. Still need to confirm this contrasting aspect in eyepiece comparison.

M31 Andromeda: found out that intelliscope really helps.. It was hard for me to see any reference stars in the clouds... but intelliscope helped...I am too glad that I have it.. worth the money... M31 not the greatest view... clouds to blame. With GSO 40mm widefield.. M32 was lil bit hard, but somehow M110 was visible. Isn't that lil bit contradicting.. any way becasue clouds, didn't think much.

M11 wild duck cluster: Intelliscope for rescue.. but not right on target.. Really hard to see in the finder. I got it once.. bad view..

In 40mm, tried to focus, but felt than focuser tube length is not enough for such a low magnification (30x)... Need to verify the relationship between maximum focuser length and min magnification supported (??)... again i might be wrong.. Need to go to dark sight for perfect focus.

Overall, to summarize..

Intelliscope is indeed a great addition for me.. surely help me in verifying locations and in bad weather. Need to learn better tactics to get warp factor below 0.5

Xcel 10mm eyepiece is probably great addition, if my perception abt image contrast is correct.. though field of view is smaller than 9mm, still image details matter

Not much happy with GSO 40mm superview...again.. weather might be the factor here.. Need to check Orion nebula or Lagoon-Triffid combo in this.

The 2" type of 25mm eyepiece...not sure if it is great or not.. lil bit of pain while swapping eyepieces, because of 2"-.1.25" adapter. Still will check in next few observations..

Indeed glad with the whole scope.. images were good as expected.. during collimation, realized there are coule of spots/scratches at the center of primary mirror. Need to confirm from Jon, if any drawbacks.. Precise collimation is necessary (double-double is the proof)..

Telerad is must... Finding Vega was difficult as hell :) .. It wasn't clouds..it wasn't location either.. but it was me.. and i call myself starhopper ;-D

Moon - NW Rim..

Date: 17th May 08, Friday
Observation Time : 11:45pm to 01:00am (1:15 hrs)
Location : SD Home
Weather: Seeing was good.. No cloud cover.. some wavy views thru eyepiece..

Highlight of the night: Crater Aristarchus and its surrounding region..

Observed few craters on Moon NW Rim and lil bit of SW Rim.

Moon phase is in its 13th day. Waxing gibbous with 95% of the Moon's visible disk illuminated.

With 32mm, prominent stuff is visible.. 32mm x 2x, 25mm x 2x combos were fine too... but 12mm x 2x eyepiece combo was THE great. It indeed showed details of craters and its surrounding prominently..

Few problems with this high magnification eyepiece combo were:
- The view in the eyepiece was moving too fast. so lil bit difficult to observe a feature for long time. Auto-Tracking on telescope would have been helpful.
- Focusing precisely at this high magnification is difficult. Why does the high magnification or short focal eyepiece focusing is so difficult?
- Felt vibrations of the cement floor in the eyepiece view. it was shaking a lot. Need rubber pads or something similar for telescope tripod.
- Preffered to observe without eyeglasses.. my impression abt 12mm eyepiece was bad before.. but this observation made me realize that the aperture size of the frontal lens is not bad.. Infact during observation I didn't feel at all that aperture hole is that small.. Thought that I should buy high eye relief 10mm eyepiece.

Moon filter was useful with 32mm... but didn't help much on 12mm x 2x eyepiece.

Crater Aristarchus: 12mm x 2x eyepiece really worked great.. crater and its surrounding were beautiful.. was able to see valleys around it clearly.. It was fun to follow the entire valley and mountains range from N of this crater to S till Crater Mauris. Mountains are visible clearly.. Couple of bright white spots on those mountains.. Shadow on east rim of the crater. West side of the crater was really bright. It sort of gave the perception how deep the crater is..

Crater Gassendi: Lil bit of shadow on east side visible.. the mountain in the center of Gassendi was strikingly bright..

Crater Kepler: Kepler and Enke were visible.. Enke was too faint becasue of moon light.. none of the moon domes were visible.. but bright rays emanating from Kepler and going towards Crater Mauris were easily visible.

Crater Mauris: Nothing special.. but because of shadows, looked like really prominent one.. Kepler + Mauris combo looks good.

Crater Babbage + J Herschel at N: Babbage and Babbage A was easy to find.. just below sinus Iradium. Compared to babbage, J herschel was too faint.. Pythagoras was still in the dark.

Eyepiece Stats..

Few bazooka stats. I need to remember these during future observations.

Celestron StarHopper 6 Dobsonian
Aperture: 6 inches / ~15 cm / 150 mm
Focal Length: 1219 mm (F/8)

Celestron Plossl Eyepiece: 32mm, 15mm, 6mm and 2x Barlow.
Apparent Field of View (AFOV): 52 deg for all. 44 deg for 32mm
Eye Relief: ?????

Magnification: Telescope focal length / Eyepiece focal length
Eyepiece 32 mm : 38x (1219mm/32mm)
Eyepiece 25 mm : 48x (1219mm/25mm)
Eyepiece 12.5 mm : 97x (1219mm/12.5mm)

Exit Pupil: Telescope aperture / Magnification
Eyepiece 32 mm : 3.9 mm (150mm/38x)
Eyepiece 25 mm : 3.1 mm (150mm/48x)
Eyepiece 12.5 mm : 1.5 mm (150mm/97x)

True field of view (TFOV): Apparent field of view (AFOV)/ Magnification
Eyepiece 32 mm : 1.16 deg (44deg/38x)
Eyepiece 25 mm : 1.08 deg (52deg/48x)
Eyepiece 12.5 mm : 0.54 deg (52deg/97x)

Maximum that can be supported on this telescope:
Max Exit Pupil : ~6 mm : Mag 25x (150mm/6mm) : Focal Length 48mm (1219mm/25x)
Min Exit Pupil : ~0.5 mm : Mag 300x (150mm/0.5mm) : Focal Length 4mm (1219mm/300x)
Best Exit Pupil : 2 mm : Mag 75x (150mm/2mm) : Focal Length 16mm (1219mm/75x)

Nikon 10x50 Binocular:
Field of View: 6.64 deg : 114m at 1000m
Exit Pupil: 5.0
Eye Relief: 17.2