Sky-Watcher Pro 100ED and HEQ5 Mount

The entire set up came in three boxes, one for the 100ED, one for the tripod and the third had the EQ head in it. Also supplied are a few tools to aid the set up. These include allen keys, screwdriver and spanners. These are not quality tools and I feel although they will do the job you are better served using your own tools, if you have better ones.

I first set up the tripod. No problems here, just pull it out of the box and spread the legs. Height adjustment and levelling are done unlocking the leg extension clamps and adjusting to your satisfaction. You will need a carpenters level for this and make sure the legs are spread fully or it will all move when you put on the head and tighten the spreader. One leg is marked N, point this south. There are a number of methods one can use to set up on the north south line as discussed in other areas in the forum, so I will not go into any detail here.

With the tripod set up and level I next put on the head. Again no problems, it is all rather straight forward. If you wish to use the polar scope for fine adjustment now is the time centre the polar scope, do this before you set your latitude angle. Once you are happy with your polar scope set your latitude and that is it. A point of caution here, check the accuracy of the latitude scale by making the head level using a spirit level, mine was depressed by 3.5 deg. This scale is rather course with 2 degree increments so a better way to measure your latitude angle is with a carpenters adjustable protractor and a spirit level or an inclinometer. The closer you get to south and your attitude angle the less frustrated you will be later.

This basic set up from scratch took me about 45 min. I was happy about that because portability and ease of set up was one of the reasons I went with this mount, rather than an EQ6.

The following picture shows the complete setup:

After dark I put the scope on with the mount in the park position. That is with the RA set to the meridian and the Dec at 90 deg. I powered up the hand set and went into the alignment mode. The first star it picked was Acrux so I entered that and away went the scope, I was amazed that it stopped slewing with the star just outside the field of the 20mm eyepiece and well within the field of the finder. I fine tuned the star and went to the next one. This is where my problems started, This was not a fault of the go-to but a problem I have with a poor horizon.

There is no way I can fill the criteria for a 3 star alignment. I had to use the 2 star option. This worked fine and all the objects I selected in the tour option of the menu came to be in the eyepiece field.

I can only put this down to taking the care to set up the scope pointing as close to south as I could and using a decent scale when setting the latitude angle. I have not yet done a drift alignment because I do not as yet own a reticule eyepiece. This situation will soon change.

The ED100 is all I hoped for. Now a Tac it ain't, but for the cost this is one good refractor. The unit has a 2" Crayford focusser and is shipped with a star diagonal, a 1.25" reducer and 2 unbranded 1.25" oculars, a 20mm and a 5mm. Both have screw up eye cups and look to me to be plossles. Star images were sharp and easy to focus and even with my polluted sky stood out well against the background. The moon was superb with well resolved sharp detail at X144. I did not push it beyond that magnification because the seeing would not allow it. This is the first time I have observed the optical illusion of the reversal of height relief in an eyepiece. This may be due to the sharp detail, I don't know for sure. Jupiter was a washout with the seeing in that part of the sky poor and fast. I will wait for a better night to view it. A pair of 4th mag stars at 1" .6 separation were easily resolved but I will need a better night to test on a closer pair.

The theoretic Dawes Limit is 1" or so therefore I will try a closer pair some other time. I did have a little bother with the focuser brake screw (for want of a better name) being somewhat loose, this was fixed with a little thread tape.

The HEQ5 mount held the 'scope steady and the vibration from any knocks soon dampened out. I did notice a little wiggle in RA when slewing a star back and forth in a medium power ocular, but this is of little concern for me as a visual observer. The www is full of ideas and fixes for those who wish to bring this mount up to imaging standards.

The things I like about this unit are: It is a neat package, no external bits to get knocked about. It is light and easy to move about. It cools down quickly and gives sharp clear images in the eyepiece. Once fixed the focuser will hold the image centred while changing oculars. It will also hold my 200mm f6 reflector.

The things I don't like are: Some of the screws (such as the azimuth adjustment) are light and crappy. I don't think better screws would cost that much and using these poor quality ones is a bit of false economy on behalf of Sky-Watcher. The polar scope reticule is too bright and the whole set up thing with the date/time circles is a bit ordinary. The instructions are a bit hard to follow also. That being said, I found the whole thing unnecessary and setting up as I have indicated above is all that is required. The star diagonal with the 1.25" adaptor in is almost too long for the FL of the 'scope and as a result the focuser needs to be almost all the way in to reach focus. Using 2" oculars will improve this and also a better Quality, lower profile, star diagonal will help.

Overall this set up is as good as one could expect for the price, Just over $3000.00. Straight from the box it all works and is easy to put together. The little things, like the focuser need only a bit of thought and practical application to fix.

by Dennis (fourtwo)