Bugdozer

I know I am late to the party here, but to answer something in the OP... I believe barrel security recess is a groove around the part that the little grip screws grip on, so if a screw works too loose to grip the barrel, the eyepiece can't drop out as it's still within the groove. My default Celestron eyepiece has one.

I currently have the following eyepieces with my Celestron Nexstar 5SE (f/10, 1250mm focal length, 5 inch aperture): 25mm Celestron Plossl (came with the telescope) 9.7mm Meade Super Plossl (about 24 years old, used to use with my previous ETX scope) 2x Barlow Lens I have no complaint about the quality of these, but as they're the only ones I have used with my current scope, I don't have any basis for comparison either! When I use the 9.7mm for planetary observing I get a nice clear view at around 130x. However, adding the Barlow pushes this up to 260x which is right at the limit of the telescope's resolving power and to be honest the images sometimes seem TOO magnified and I end up taking the Barlow out again. However, I'd still like to have a slightly closer view sometimes. So, would I be better to get a slightly shorter length eyepiece, such as 6mm? Or would I be better off using a lower power Barlow, like 1.5x? I am prepared to spend some £ to get good quality, I'm not on a very tight budget. I will admit I don't fully understand the impact of things like eye relief and field of view in a practical sense. My second question goes the other way - is there any benefit to getting a a longer length eyepiece than the 25mm for deep sky observing? I do have trouble getting things like the Pleiades and Double Cluster completely into the field of view, and if there's any benefit to brightness or clarity from a lower power eyepiece then I would consider anything you might recommend.

Yes, I can put it into Equatorial mode but it's not the easiest scope to do that with. I'm not expecting Hubble quality results, the mount is not really ideal for photography, but as you say, planetary could work well. I'm awaiting delivery of an eyepiece projection adaptor right now. I have some good photos of the Moon and M13 taken at prime focus with extension tubes, but I really am still learning!

Who knows? Maybe because I'm using a Hotmail email address?

OK this might be a very off the wall suggestion, but I actually got caught out with this on my Celestron go-to... Are you entering the date in American format? Mine requires that. Otherwise it gets confused either just a little bit, or a huge amount. What you describe here sounds like it might be the same problem, rather than the screw.

Hi, I am Simon, pleased to be here! (I signed up for the Cloudy Nights forum too, but was instantly banned before I had even posted. Stuff that!) I currently have a Celestron Nexstar 5SE which I am also teaching my teenage daughter how to use. I have been into astronomy my whole life, I initially had a crummy refractor from Argos when I was about 13 (almost impossible to see anything due to the wobbly mount) then a Meade ETX90 when I could afford a "proper" scope, and now the Celestron. Although I have been observing for a while, I am only now taking my first steps into photography through the telescope. I am sure lots of you will be able to advise me!