John

I would not consider the Startravel refractors for mostly planetary observing. They have too much false colour. Stick to F/10 refractors, F/11-14 mak-cassegrains (which they all are) or F/6-F/8 newtonians. Getting something on a tracking mount for £300 or less is going to be the challenge I think.

Lovely images - thanks for posting them Just how Mars looked with my Tak 100mm refractor a few nights back.

As you gain experience you will see a little more detail with the 150mm and the larger scope will show deep sky objects better because it gathers more light. Not very large differences but they will be there, a bit more so on deep sky objects, as you become used to observing.

No problem - opinions on eyepiece performance are often very personal

The details shown of the planets are about right for an experienced observer under good conditions but the size of the planets as they will appear in the eyepiece is way over stated. They will be much, much smaller than this. More like this: Also, you can see quite a lot of deep sky objects with 80mm - 150mm scopes. Lots of them will appear small and fuzzy but that is also the case with larger scopes.

One of the admins will need to close this account down now. You are only allowed one. I have asked them to do that.

You might need to change your forum ID but the 6 inch dob is an excellent scope. I would have an F/8 one over either a 90mm or 102mm F/10 achromatic refractor.

Very nice drawing Chris and of an unusual subject

Mmmm - not sure about that !

Those HD orthos are pretty good if you are OK with the eye relief, FoV etc ! I had the University Optics version for a while and it was excellent;

With which of your scopes ? The barlow will work with those eyepieces but whether the magnification produced is useful will depend on the scope, the observation target and the seeing conditions. I use the 2.25x Baader Barlow with a 21.5 - 7.2mm zoom eyepiece to give a 9.55mm - 3.2mm zoom. That is a very useful range with my refactors. Not so much with my 12 in dobsonian.

Back in 2016 I purchased two telescopes which I hoped would deliver pretty much as good performance as you can get from their respective apertures. I'm pretty confident that they both live up to that expectation. While I can't control the seeing conditions I think that I can recognise what they are reasonably well now and adjust my observing accordingly. I'm less certain that my eye is able to take full advantage of what these scopes can do when the seeing conditions are good enough to allow them to perform to their full capability thought. I'm the weak link in the optical system I expect now There is a slight irony that it takes until the latter part of ones life to be able to afford excellent optics which you might be better able to exploit more with younger eyes and younger energy levels. But I soldier on anyway Sorry - nothing scientific in this post

I've been an astronomer for 40 years but I've said "no". I do lots of astronomy at home so it's not a priority when on holiday.

You can do quite a bit to ensure that you get as close to the best performance that is possible from a given aperture though and as often as the seeing conditions will allow. That's part of the fun of observing IMHO - pushing things as far as you can My guess is that the capabilities of a lot of scopes are not really fully explored. Hopefully this thread and others like it will provide some tips on how observers might get a bit more from their instruments before succumbing to the urge to upgrade

Agreed. I really like mine

Not long ago a certain brand of dobsonian was being advertised as having a "1/12th wave" mirrors without specifying whether that was a RMS or PV value. When I queried it the vendor said it was RMS and the PV was "probably" around 1/4 wave.

That's what I mentioned a few posts back ! It would be worth seeing if the piece marked "X" above will screw into the diagonal.

99% of my observing is from my back garden which is fortunately just a few paces from where my scopes are stored. My skies are Bortle 5 as well and there are plenty of obstructions and some light pollution issues here but the sheer convenience means that I can observe as often as the skies are clear and at really short notice.

I'm going to make it full screen, put my lap top on a hill about 50 km away and observe it at 500x with my Tak @mikeDnight would still see more detail in it than I would

Then what ? (the 17 popped out a little easier for me when I removed my reading glasses)

If you can get the silver barrel out of the top of the barlow lens, it may well screw into the diagonal then you can use it.

It means nothing really. Plan on 150x - 220x as the maximum useful magnification. Telescopes for astronomy are more about light grasp than magnification. Most observing is done at 50x - 100x in reality. Stepping up from the stock eyepieces is a good plan and not using the barlow lens is another one. The BST Explorer eyepieces are a very good move away from the stock eyepieces: https://www.firstlightoptics.com/bst-starguider-eyepieces.html Is your scope the dobsonian or the equatorialy mounted 150mm newtonian ?

That is part of the finder scope. Lots missing there including the objective lens ! I think the silver barrel for the diagonal might be stuffed into the barlow lens that you have.

Opticron Tiaga 8x25 - Very bright for their limited apeture. Sharp too. Zeiss Jenoptik 8x30 - I seem to have two pairs of these now. Russian Komz / Baigish 8x30 - Zeiss copy from the USSR (as was). Sharp, rugged and low cost. Swarovski Habicht Tirol 8x30 - Probably 50 years old. Battered but very sharp. Very light as well. Boots Fleet 7x35 wide angle - decent Japan optics. 11 degree field. Helios Nature Sport Plus 8x40 - nice day to day birding binoculars. Helios nature Sport Plus 10x50 - as above. Pleasant to hold and use. Opticron Vega II 8x56 - Japanese made but not out of the ordinary. Competent performers and good for travel because of decent light grasp with light weight. Opticron Oregon 11x70 LER ZWCF - Japanese made and much better than the current Chinese 11x70's in my opinion. The largest binoculars I own and quite easy to hand hold.

The diagonal should look like this: