iPeace

I went through this myself, and though I'm not much wiser, I don't mind sharing... I've come to the realization - and one's milage will vary - that it's all compromise. Always. Unrelentingly. It's never going to be perfect - whatever that looks like, anyway. But if you do your homework, it will always be good enough to make you happy, ecstatic, even. You pick your premium. Whatever's important to you - size, weight, cost, light grasp, resolution, cooling, collimation, mounting, transport, etc. - a solution is available for your priorities, and you'll love it, exactly because it fits. Plenty of folks fully enjoy their f/5 (or even faster) scopes for visual. They've often chosen eyepieces and other accessories to match. You know what you really want. Go for it.

Pentax XL Zoom: very nice build, very nice views. Relatively heavy and bulky, but no more so than many other very nice eyepieces (I've switched to more compact types). Baader Mk IV Zoom: nice build quality, to my eyes the views are just about as nice as the Pentax at less weight and bulk. I've kept this one. HyperFlex Zoom: the most compact and lightest of the "mid-length" zooms I've tried. Build quality is less posh, but solid enough and the views are good. Excellent value; after comparison I kept the Baader but only for its more posh feel. TeleVue Nagler Zoom: at 3-6 mm, limited to use for high magnification, but so amazingly useful and fun, premium quality, compact powerhouse. I also own the 2-4 mm version, now no longer in production. Between the Baader and the HyperFlex, I'm inclined to say that the price differential gives you more additional build quality than actual additional optical performance. If you like your eyepieces light and compact, the HyperFlex will serve you well - surprisingly so, with a Q Barlow for higher mags. If your OCD is of the touchy-feely variety, you may enjoy the Baader more. Good luck, and enjoy!

As @vlaiv mentions above, I've acquired and used a couple of newts from TS. The white one shown above is a 6" f/6 branded TS, made by GSO, and doesn't seem to be offered by TS any more. I am inclined to assume that the PHOTON is assembled by TS from quality (GSO) parts, as is the 8" f/6 I got from them: https://www.teleskop-express.de/shop/product_info.php/info/p5052_TS-Optics-8--f-6-UNC-Planet---Newtonian---Fused-Quartz-Mirror---Carbon-Tube---made-in-Germany.html As to the effectiveness of f/6, it does work very well, but I've never used a faster newt, so I can't really compare. My f/6 newts are easy to collimate. I also own a 6" f/8 - which, of course, has the same tube length as the 8" f/6. So...I suppose it would be helpful if I could tell you that the 6" f/6 works just as well as the 6" f/8 - and is easier to transport and mount... Well, I hesitate here. I haven't mounted them up together to see which was best. I've used both (on separate occasions) to observe the Moon, and I didn't notice any real difference. I guess the theory is that the f/8 should be better than the f/6 on Moon and planets, but from my little bit of ocean floor (we're below sea level) it doesn't seem to matter. Anyway, it's a bit moot for me, as I've got the carbon 8" f/6 and the other two newts get no more use (you'd be welcome to try them out, it's just that pesky North Sea that's so inconvenient). I can confirm that the 6" f/6 works well on a Losmandy AZ8 mount, and fully expect it to do equally well on a SkyTee. I've reported on how well it works on doubles. Best of luck.

Arrived packaged in a manner of which I myself would be most proud, from the true giant among gents that is @Alan White

I often find that 120x is most pleasing for Jupiter and Saturn. The view is great, and I always try more magnification, but most often I'll return to 120x to enjoy that less-magnified, but nicer, view. So based on my own experience, I'd suggest getting a 5mm first. That will make you happy and wanting even more...and when you eventually try something below 5mm, you may well find that you're glad you have the 5mm to fall back on most nights.

Well, the best I can measure gives a result of 3.8 cm added to the path, perhaps 1-2 mm more. Not exactly compact...but, as stated, the added length is a feature for me, not an issue.

Apologies for the delay. I will only be able to measure approximately (hopefully tomorrow), so I hope that will be of use. Alternatively, you could wind some narrow isolation tape around the eyepiece to fill in the undercut just enough (I understand if you don't want to do this, it's just a suggestion). I think other SGL friends have done similar things to solve this problem.

I'm travelling abroad for a few more days; will do my best for you when I get back. Off hand, I assume the shortest light path would be obtained by just using the diagonal without any additional parts? Do you actually need the Baader bits? I need them to lengthen the path for use with my Borg refractor.

Dear OP: No.

Having used the Ercole and having read a few less than positive reports on SkyTees in the wild, I dearly wanted an AZ8 and have enjoyed it immensely. Thing is, I'm not convinced it actually does anything more than a SkyTee. Granted, the AZ8 will not fall apart - which is quite a boon for those who have gone through a few SkyTees - but if you do manage to find a good SkyTee and keep it in working order, the price of an AZ8 is very tough to justify...