DAT

Thanks, with the 18mm still getting good views, just a bit frustrating when there has been so few clear nights not to be able to go higher. With the same scope and the same location I have managed to get x170 so I will persevere

Well the problem is not observing too close to the house, or on concrete or anyone growing certain substances. Took the scope out 1+ before I started observing, on a wooden base on the grass 5+ metres way from the house and was tested the view on targets straight. From looking at the diagram above I am not really sure what is going on. I would like to rule out collimation as defocused stars appear as nice concentric rings. This issue has been going on a while and I know in the past I had not collimated the optics properly. Whilst I thought it could be tube currents, the scope was well acclimatised. I have loosened the locking screws on the primary and brought it down ever so slightly to see if that makes a difference. The sky seems clear from where I observe but even on moonless nights, it is very bright (Wembley stadium is not far off) However, I know from before Christmas and from viewing with a 130p last summer, that it is possible to see a lot more detail. I can only make out a few stars in m67 and I think I could just about see one or two in m3 with averted vision although that could be wishful thinking. That has to be one of my favourite targets so far, spectacular even considering all of the above

Thanks for all the responses. It’s obviously difficult for me to differentiate between bad collimation (although I am ruling this out), bad seeing and tube currents. However, I have had the same problem several times in a row and at the next opportunity I am going to try putting my scope further away from the house as I am wandering whether heat coming off the building could be affecting the view.

Very useful pictures there, I will hopefully confirm tonight but tests I have do look like tube currents

Thanks Paul, I personally think/hope nothing is wrong, I suppose I am looking for anyone else observing under similar conditions that may be able to confirm or otherwise. So far this has been the case 2 nights in a row, let's see

The last few days many people (in the UK) have finally been blessed with some clear skies. I have noticed that several people have gotten some great views of various targets. I have been struggling to get a sharp image at anything above x 100 (more or less). In my 8" dob (1200m fl), I go from using an 18mm ep to an 11 and unfortunately sharpness decreases significantly. I leave the scope outside for at least 1 hour although I do not use the fan. It is likely to be collimated well too (some kind souls on this forum and another have confirmed). Can tightening the primary screws too much cause this kind of problem ? ( mine are only finger tight). I have finally managed to locate a couple of globulars so it is very exciting but just can't use anything above x100 to see any details. Could this be the seeing conditions? I observe from a bortle 9 but have in the past been able to use much higher magnification (x170). Any help is much appreciated

How bad is you astigmatism? I have + or - 2, can’t remember, I find I can use 18mm er but 20mm is more comfortable. Good to hear this ep did not need any modifications to see the whole view

With all the clouds it’s difficult to see anything at the moment. Maybe someone else can verify but I even on clear nights, seeing conditions have not been great. I have been enjoying various clusters but struggling with faint objects and anything that requires high magnification, made worse by the fact that the fact I observe from a light polluted area. Best of luck to you!

Would you say you prefer your apm to the morpheus 12.5?

Nice idea, had not thought of that. I am assuming thought that would act as a field stop and reduce the foc or am I talking rubbish? Either way, I think it’s a good option. Thank you

Actually I do, I swap from hovering over the lens to pressing against the eye cup. I just need to practice

Thank you, is that also known as the Orion LHD? I was hoping for a 1.25" to make use of filters I already have

Has anyone got any experience with the above eyepieces? (I have a gso 8" f 5.9) Someone on CN pointed me in the direction of Siebert Optics, specifically the Ultra range as I wear glasses and looking for a large fov. Seems like a nice small scale company but cannot find any user reports on those fl in that range. The spec of the 15mm seems spot on, 13mm may not have enough er for me. Longer focal lengths seem very well priced. I was also looking at the APM option, lots written about it and the main problem seems to be EOFB. With my experience I probably would not notice that although I do observe from a light pouted area, could that be a problem. Would be good to hear from someone that has used this Morpheus 12.5mm keeps coming up and I have used a 9mm but whilst amazing, it isn't my favourite. Due to lack of experience, I find eye placement a bit tricky which can lead to black outs and an off putting brown if observing the moon (CA?). Otherwise its great, would be happy to buy used... Other options in similar focal lengths then get even more expensive and heavy (TV, ES...) Your thoughts and/or alternative suggestions would be much appreciated

Another vote for "Turn left at Orion". The various apps are great but would highly recommend a planisphere. With this and the book, you can literally walk outside, identify the visible constellations, and then search for targets within them. The advantage over an app of doing it this way is you tend to remember the "layout" of things and can then find targets unaided. That particular book, (and others), together with the planisphere, help to identify things according to the season and time

Is it worth painting the screws or is that overkill? The ones I have ordered are steel and could reflect stray light…

Thanks for the replies, I think I need M4 x 35mm stainless steel screws. Have found some fairly cheap on eBay (about £6 for 5). Will leave the washer modification for later as I think collimation is looking good for now, might even be able to see something in the next week or so…

Does anyone know how/where to get thumb screws (in the UK)) to replace the screws to adjust the secondary on a Stellalyra? I understand bob's knobs are an option but they seem expensive. I believe I need 35mm but not sure on the thread required. Is it a question of taking a screw to a hardware store and seeing if they have one that matches? I see that a lot of people have chosen to add a washer to the secondary to allow rotation which is not possible because of the indentations the 3 collimating screws fit into. How important is this modification? If the scope is collimated or the secondary does not need to be rotated, is there any benefit to this? I have read a few threads but could not find the answer to these questions, thanks in advance

Nice work! I have managed 4 in a few limited [by the weather mainly] sessions over a month and I am super happy. The whole catalogue must be thrilling!

With regards to some of the collimation tools mentioned, if one has a 2" focuser and a good 2" to 1.25" reducer, does it matter whether one uses say a 1.25" or 2" laser or concentre?

Thank you, a nice selection of opinions and advice. I think given I have a Chesire, a concentre would perhaps be overkill although as someone has pointed out, it would be even better to try and see what works. Not sure about the laser either, as I have an 8" dob some seem to think this is not necessary, I think I would like to improve with what I have and then perhaps think about what would help to be more precise. I understand this is not strictly necessary but I enjoy the challenge of getting things just right (I have an 8" stellalyra f5.9 dob)

Hello there, I am still struggling with collimation but getting very close, I think...As soo as I can, I will take up someone's kind offer of an in person tutorial. For the time being, my cap and Chesire sight tube will certainly be good enough but was wandering whether someone could recommend a good laser that I can buy in the UK. I have been suggested everything from Glatter to Baader, Astrsystems and Ho-tech. All have pros and cons from price, to availability in the UK and so on. I am thinking of a laser to collimate in the dark and eventually to be more precise. Also, what do people think about a Concentre. Would that help for the secondary? I have posted on CN and had some advice already and as usual there is a wealth of information coming my way. Am interested in an SGL slant on the matter. I am in no rush to make a purchase as I have everything I need to get the job done now. Thanks in advance

There are some great pictures taken with a phone on this thread. I am wondering if anyone has had trouble with the size of their eyepieces? I have a reasonably priced celestron phone holder but it can only clip on to the stock eyepieces, which I no longer have. The eyepieces I "now" use are all too wide for it. When I did take pictures, sticking a timer on also helped as it gives the scope time to settle down in case you knock it when taking a picture, especially if you are not using a dob and the tripod is shaky. (I say "now" because I have had consistent cloud cover for feels like months )

I do not have much experience but the SL 30mm uff is the eyepiece I use the most (8" dob), not just a sky scanner. Everything looks good through it and sharp to the edge. I just have problems with the rubber eyecup which tends to slip off when I try and fold it up back up. I wear glasses and switch between having it down and folded up whilst pressing up against it.

Great insights on this thread, learning lots.

As a beginner it’s difficult to separate collimation issues from poor seeing. Scope is usually out a couple of hours before I start seeing, so do not think that is the issue. Do the eps need to acclimatise as well? The sky looked so clear the last two days I could not imagine the seeing conditions to be bad but I assume bad conditions are not always “visible. Will try and perform a start test again and see, last time I tried I would say it looked like a collimation issue as I got concentric rings but slightly off and very fuzzy. Thank you all for you help as always.