Grab and Go

[michael.h.f.wilkinson]

Thanks for the details. I was thinking about a more open construction for my 4.5" F/4.4 rebuild, but will opt for a closed structure. At F/5 or shorter, focusing is always going to be a problem, especially at high magnification. Coma is also a fact of life on such systems (even the best). Cheaper, more narrow apparent FOV EPs are going to be more forgiving, and kids can more easily handle the larger exit pupil that entails. I would use it as a wide field instrument personally.

[spaceboy]

Nah...... This package is on the long haul back to China guys. It not only didn't sail my boat it sunk it like the Titanic. I still have wet feet in astronomy but I know enough that it wasn't going to work for me and after the lemon my son had for Xmas I didn't want to do it to him again. As for the wife sadly she will have to make do with the bins and the occasional look through the dob. If one good thing has come from this is that I'm sold on the idea of a wide field scope but which one will work after this I don't know

The threads back up for any suggestions guy.

[spaceboy]

After weighing up the options a Startravel 102 seemed the next best choice but I just couldn't find the ST & mount at a second hand price I was willing to pay. This also gave me time to get cold feet on the idea of having to deal with the CA that would be more apparent in a short tube frak than had been experience in the F/8.3 EVO. Although I didn't have a very good experience with the Heritage, after what a couple of members comments in this thread had said about their experiences with 130P's I decided to put this down to the open truss design and using the scope on a less than idea full moon night. There were times when the image in the center of view wasn't that bad so I decided to look for more reviews of the solid tube version.

As the nights are getting darker sooner and my boy is eager to get some observing in while still going to bed at a reasonable Hr I decided dealing with dew and CA were not worth the some what high cost second hand and keep an eye out for a 130P solid tube instead with the intension of using it on his Celestron AZ mount.

As luck would have it a 130P AZ GOTO came up at a reasonable price and the wife and I thought the addition of a GT mount would help my son get to see more of the sky before bed time. The deal was done and I would have a Grab and Go and my son has a good sized scope that will show him the sky with the minimal of effort.

I was dubious to how it would perform but we managed first light last night and although the dew would soon have everything soaked and the seeing slowly deteriorated I have to say I'm happy I didn't give up on the idea of a 5" fleck all together. The moon was high in the sky and while not full like last time it was still lighting the ground. Getting to grips with the AZGT took longer than wanted but it allowed plenty of time for the scope to cool. Once the alignment was completed I was surprised at the accuracy of the mount and often placing the target near center of view each time. The bigger surprise was the performance for me as I was expecting to see similar performance to the Heritage being the same mirror set in the two scopes. The moon was pretty much the same as it was in the Heritage only that bit sharper but I put this down to the position in the sky. Jupiter was also the same but this time all the moons were equally sharp until placed at the outer edge of view where coma was visible. As the scope is more or less my sons we used his set of standard come with a scope 9, 10, 20, 25 plossls, x2 barlow and a cheap 40mm 500 plossl which my son likes despite giving an exit of 8mm. Other targets were M57 which despite being small with the 10mm EP was pleasant enough clearly showing as a hoop. M13 was reasonably low in amongst the LP and for me didn't perform at it's best. I'm keeping an open mind and putting it down to the position and bright moon so I would have to give that another go on a night more in it's favor as it was no where near as good as it was in my smaller 100mm refrator given similar conditions. There were some individual stars but for the best part it was a smudge. The double cluster was a treat fitting in the FOV of the 25mm EP. The coat hanger and M45 also achieved this with the 40mm. I know the 8mm exit makes this less than ideal in the scope but it was nice to see the clusters in an almost binocular-ed FOV.

My conclusion is that the 130P is not actually a bad scope as it has sides on it and a more substantial 2" focuser holding the EP. It's no where near as portable as the Heritage and with the GT mount it's even less so but my son was very impressed with the views and the wife more so when she later came out. The AZGT mount dose a good job of getting the scope on target but the R&P focuser requires a little heavy handedness (even after some adjustments) to get focus and this soon travels along the slim legs of the tripod back up into the image making for a flickering image of several seconds. A small bag of sand will hopefully help out with this. Later trying the scope with my TAL EP's the images improved slightly so I think it will keep fussy old me happy as a grab and go even though it will be somewhat of a handful to grab. The only real critique I have is if your not careful the power lead gets wrapped around the mount as it traverses the sky and in the dark this can be overlooked and could end up wound up tight.

I think it's fair to say I didn't do a fair evaluation of the Heritage as the odds were stacked up high against it and I would have been interested to see how it performed with a light shield and no moon. I still think the 1.25" only helical focuser was far too sloppy and the weak part of the scope that allowed miss collimation to add to any stray light issues. My doubts to the performance of the 130P mirror set have certainly been put to rest. While it's not going to blow you away with subtle details on DSO's, for it's size it's not a bad performer at all. It was though interesting to compare the size of the 5" scope next to my 10" dob. Given the 250PX mirror is only double the size the OTA is much more than double the dimensions.