First night of the season and some tests

[iamjulian]

Too long since I wrote an observing report! Out for the first time this side of the solstice last night. There was a fair bit of thin cloud floating about, but plenty of big gaps. Forecast for the rest of the week looks good, so may even try to get to a dark site at the weekend. I wasn't really looking for anything last night, it was more a chance to test this season's changes to my set-up. So telescope out well before dark to give it a chance to cool a bit.

First up, a new eyepiece. Since splashing out on a 13mm nagler late last year I started to notice the quality difference with my existing skywatcher plossl and revelation eyepieces. For the first half of 2012 I was using the stock 25mm EP as my widefield. I used to have the Meade 5000 32mm super plossl, but found the combination of a washed out colour and seagull stars was too noticeable. The 25mm with a smaller exit pupil was nice and dark, but the seagulls were even worse. I considered a 30mm Aero and a 31mm Aspheric, but the reviews for the 24mm Meade SWA were too good to miss, especially at second hand prices.

Focusing on the double double, the Skywatcher view looked like it had the twirl filter applied to it in photoshop. Much worse than I remembered. I almost thought that I had messed up the collimation or something, but when I swapped in the Meade, the stars were pin sharp across the whole field of view. The view itself, although only 68 degrees, was not too dissimilar to the 82 degree nagler, and the stars really were sharp all the way to the edge. I think these things are about £200 new at the places still selling them, but second hand for under £100 is a great price. I found it quite difficult to tighten the two little screws that hold the EP in place when the eye cup was twisted all the way down, but it wasn't really a problem. I also noticed it seemed more prone to what I think is called vignetting. Where as your eye moves, a black crescent shadow appears and disappears at the edge of the field of view. Am I using the correct term? It was more noticeable when I had the eye cup all the way down and was just hovering my face, rather than when pressing my eye to the eye cup.

Second test was my new levelling base. I decided against chopping up the existing base, and instead cut a disk of wood slightly larger than the existing base footprint, put levelling feet on it, and painted a setting circle around the edge. Centred Polaris and looked up its Azimuth. As a temporary pointer (this new base is still very much a work in progress!) I set a block of wood on the top part of the base with an allen key pointing down to the degree circle at near zero. Punched up the coordinates for Caph using the StarWalk app on my ipod, then spun the telescope until the allen key was pointing at the correct number. Bang on! I don't have a wixey. Yet. Push to is going to be a great help finding some of the more obscure objects.

I finished off with a quick look at M13, and the ring nebula. It still wasn't properly dark, but two amazing objects in a great location at this time of year. I've love to be able to show Messier some of his objects through a moden day telescope. He'd be amazed. Off to B&Q later for some 3mm hardboard - trying to paint tiny numbers on OSB is too difficult. I'm going to give it a nice smooth top and make my life easier. I'll stick a photo in the DIY section when it is completed.

Thanks for reading

[Beulah]

Thanks for that Julian, especially about the new EP, I've been waiting to see how you got on with it.

Don't know about Messier though - he wanted to avoid his catalogued objects like the plague!

[swamp thing]

I think the effect your talking about sounds like kidney beaning. If its what happens when bringing your eye too close. The SWA"s are great eyepieces that you can pick up at really good prices.

[andrew63]

Nice report on your progress - sounds like your about ready for the autumn sky! And i agree about those meade swa much underrated - i've had the 16 20 and 34mm and all have shown sharp stars to the edge.

andrew