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Discovery DHQ 8

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Date: NA
Price: $449.55 + 49.00 for the upgrade package
Design: 8 inch Dobsonian operating at f/6 for a focal length of 1219mm
Description: Medium reflector on a Dobsonian mount. It ships with two Plossl eyepieces (25mm and 10mm) and a 6x30 finder scope along with premium Pyrex mirrors.  The upgrade package includes two more Plossl eyepieces (15mm and 6.5mm) as well as an eyepiece rack and moon filter.

The Review

This is my first scope.  I went with the Dobson design because of its cost effectiveness, ease of use and compactness for its aperture.  I hunted around quite a bit before settling on Discovery.  Here were my reasons: optics made in America and individually inspected; dent and heat resistant sonotube rather than conductive steel; vented mirror similar to Celestron; painted-not wrapped; aluminum RP focuser; adjustable trunions instead of goofy springs or counterweights; aluminum cell with no clips and lastly I prefer to do business with a small company.  I also sprung the extra fifty bucks for a Pyrex mirror because it came with enhanced reflectivity.  Thus customized, it took 20 days to arrive.  It assembled in two hours.

This scope has performed very well.  Its images are generally comparable to 10" Meade or Orion models I have seen.  It had a few mechanical quirks, in particular the azimuth was a bit sticky.  Fortunately, the Dobson design lends itself to DIY improvements.  My remedy was to high-center it on a wooden donut I made that sticks to the underside with velcro.  (A wadded dish cloth also works.)  Also, at the manufacturer's suggestion, I lubricated the azimuth with car wax.  This was only a problem on asphalt, not on turf, and anyway it is solved.  The brand-X supplied Plossls were good, but not great.  I replaced mine with University orthos which really bring out the scope's potential.  The finder (6x30) worked pretty well, but I added a unity finder.

Reflector optics were once thought to be inferior to refractor lenses.   Nevertheless, the planets resolve well with this scope and its large aperture makes it very tolerant of filters and a Barlow.  On a good night much detail can be seen on Jupiter, including festoons, satellite shadows and a slightly pink hue to the red spot.  Saturn appears as a 3D object and the Cassini division is inky black.  Several satellites are visible.  The inner and outer rings are of differing brightnesses. Uranus is a tiny bluish pin point.  Venus shows its shape even in gibbous phase.  Viewing the moon is like being in lunar orbit.  Terracing on crater walls is obvious as are numerous central spur peaks.  Occasionally rilles are visible.  M13 resolves into individual stars.  M31's two companion galaxies are visible, as is a dark dust streak.  M42 appears with a greenish hue.  M33's fuzzy nucleus is easily resolved as is M1 from the suburbs.  Star hopping in Saggitarius is a trip through a celestial candy land.  I have not tried and double test stars, but the ones I have seen split well.

All in all, this scope has performed very well and I am always surprised by what I see.

Submitted by Russell Hopkins - rah4@hotmail.com - NE Ohio


The Review

Yesterday our new Discovery DHQ-8 arrived. I guess I need some help here and I'd like to get a few comments and suggestions.

The DHQ arrived in two large boxes. The box with the base had some crushing of the corners and a split. The hardware was backed loose and was rolling around in the box. Fortunately, it all was there. There were some minor chips in the Formica® on the circular base on the corners of one of the supports. Discovery CS said they would be happy to replace them, which was fine by me. I'll address this issue with them at a later date.

Anyway, I was very disappointed in the quality of the packing done. I've done lots of backing and shipping in my day and this was what I would call "minimal". However, nothing was missing or damaged other than the fore-mentioned.

Another disappointment was the manual. It was about 20 pages of Xerox® pages with a staple in the corner. Guys, you spend $500 for something, this is tacky and doesn't give you that needed feeling of I didn't waste my big bucks on this….

Assembly was pretty straightforward. We ran into a question with the rubber feet on the base as the instructions said their were pre-drilled holes. I called CS and they basically said these are self-tapping screws, just screw them in at 120° apart. I did as instructed and no problems.

I installed the primary mirror in the sonotube and was very impressed with just the sheer mass of the whole thing. The focuser was very smooth and has large knobs, something very important in Michigan in January.

A quick check with the laser collimator showed the alignment was very close so I decided not to mess with it.

I purchased the additional eyepiece package which included a 15mm and a 6.5mm Plossls, moon filters and dust caps. It was apparent early on the 6.5 was going to be completely useless and I'll check and see if Discovery will swap for something in the 30 to 40mm range. The supplied 25 and 10mm eyepieces also had no discernable manufacture stamp, but it was getting dark. Only the 25 has a rubber eyepiece and the 6.5 and 15 came with eyepiece cases. The other two came in small cardboard boxes. I will have to purchase some cases for these as I don't think the boxes will last.

So, a clear night being forecast, I put it out in the garage to and set the alarm for 0300. The primary object of the exercise was the planet Mars.

I got up and carried the tube and base out side and set up next to the pickup truck. It became very obvious that I had a problem. Mars is about 15-20 degrees above the horizon and that meant the eyepiece was about 3 feet off the ground. I'm much more used to our ETX and the tripod doing some observing standing up. This was a major problem and observing was very uncomfortable.

I tried a 5 gallon bucket which helped a lot, but it was still very uncomfortable to use. This is not going to work, especially when there is 2 feet of snow on the ground. 

Ok, I know there's a lot of folks on this board from the snow belt. I'm asking for suggestions.

My thoughts are not to raise the bridge, just lower the river. I'm considering putting the base on the tailgate of the pickup or getting some cinder blocks and making a higher stand for this. A lot of our observing is done in the southern sky on the lower horizon (Orion, Sag, etc). Suggestions?

I started with the 25mm and worked through the 15 down to the 10. I ran into trouble keeping Mars in the FOV with the 10, but it was pretty easy with the other two. The image of Mars was very good with a dark blemish on the surface. I did not use our filters or our Barlow. The 10mm gives about 120 power, which was probably over-powered for the seeing conditions. I will be trying the 25 again with the Barlow and keeping the 10 for better mornings.

All in all, if I can find a more amicable way to look through this, I'm very happy with the images I did see. I spent some time looking for M13, but I was getting shredded by the Michigan state bird and didn't have my star charts out and didn't find it. I picked M13 as it is pretty high in the sky and I wanted to see how things would handle with an object at near zenith.

Submitted by anonymous - large_o123@yahoo.com - USA

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