John

It's just started to rain quite heavily 😒

My scope is still out but undercover as well. You never know ......

My TMB/LZOS 130mm F/9.2 triplet has a similar feature but it is a 2 inch format extension. It's very solid even when extended to it's full length. A number of the APM/TMB/LZOS refractors use such extensions.

I thought I would post my astro "workflow" this evening to help newcomers to the hobby 🙂 1. Look out door - notice clear sky with stars showing. 2. Put out tripod with mount attached. 3. Put out scope to cool for a few minutes. 4. Pop eyepiece in focuser and snap photo for SGL. 5. Post said photo on SGL: https://stargazerslounge.com/topic/274300-show-us-your-set-up-in-action-at-night/?do=findComment&comment=4432599 6. Go back outside full of anticipation of lovely Saturnian views. 7. Notice that the sky has completely clouded over from the west 😒 8. Notice that further west cloud was solid, even thicker and heading my way. 9. Bring scope, tripod and mount back inside. 10. Reach for beer from fridge and type grumpy post on SGL. Doh !!! - stupid hobby !!!! 🥴

A whole bunch of boxes need to get "ticked" for this one to be achieved visually. Over the past 10 years I've had the right eyepieces, the right filters, enough aperture, enough experience (well, almost !), good star charts, good advice etc, etc and yet things only came together a couple of times over that period from my backyard. If I'd travelled more to really dark sites I could have improved on that though. But at least I've had a couple of glimpses of it 🙂 I'm no imager but I'm told that the Horsehead is relatively easy to image and is quite straightforward with an EAA setup.

My ED120 on the Giro Ercole mount eyeing Saturn this evening. Simple setup. The Ercole is actually flat black rather than the dark blue that it seems to show as in the mobile phone camera 🙄

That's interesting because I was looking, in vain, for a TV Genesis or 101 when the Vixen came up for sale on here back in early summer 2007 🙄

The thickness of a Sainsbury's 4 pint plastic milk carton 🙂

Last time I had an ST80 the lens retaining ring was at the front of the objective cell. It had a plastic rim around it and to get any grip on that, the dew shield had to be removed. I think that slid off the objective cell as I recall. The retaining ring could have been overlooked though because, unlike many others, it did not have any location slots or holes in it to take a tool. It just has a smooth top plastic rim. I've had a look at a Skywatcher Evostar 90 objective cell that I happen to have knocking around this evening and that uses a similar approach. This is not my ST80 but it is how it looked with the dew shield removed. The lens retaining ring is marked with red arrows:

The Svbony zoom can be bought new for £120-£130 last time I checked. The BHZ barlow costs £114.00 plus P&P currently from FLO.

Magnitude figures for deep sky objects can, oddly, be little or no help in guaging how easy or difficult it will be to see an object through the eyepiece. Surface brightness is often a lot dimmer than the integrated magnitude figures quoted in sources such as Wikipedia but it is this, plus a host of other factors, that determine the actual visibility at a given time. The galaxies M33 and M101 are good examples of this.

I have owned 2 of these but at least 10 years apart ! I picked up the latest one a couple of months ago. It is the 200P Classic model pretty much unused. I was expecting some stickyness (for want of a better term) on the azimuth axis and when I first lighted the scope, it was there. The scope was useable but frustrating at high power because it was all to easy to apply too much push in azimuth to get it moving, overshoot the target, then do the same coming back the other way ! I tried different tensions on the central nut and bolt but that didn't really help. I then reminded myself of the old "milk carton washer" modification that I had used all those years back with my other 200P dob. For this new scope I found that adding a single large washer (about 100mm in diameter and with a 12mm hole in the centre for the bolt) made a noticeable difference in reducing the "sticktion" to a low and acceptable (for me) level while retaining stability in the mount base. I put my milk carton washer between the bottom board and the stock white teflon washer. I then bolted the mount base back together and applied enough torque to the central locking nut to hold things together in a stable manner. I think the way this works is that the additional thickness of the DIY washer takes a little of the weight off the 3 teflon pads that are used as the azimuth bearing. Some people find more than one DIY washer is needed but in my case one did the trick. I realise that other people use lazy susan type bearings and other approaches and those undoubtedly work for them. Different people have different preferences for ease of movement etc so this is why there is not 100% agreement on the best approach. People find what works for them 🙂 I have found the milk carton washer modification has worked for me 3 times now - I also owned a 10 inch Skywatcher dob a few years back and did the same thing on that - 2 washers needed with that one I recall. I have also owned dobs with lazy susan type bearings as standard and those needed some friction adding to the motion to get it to suit my tastes.

I found seeing IC 434 very, very difficult. I've looked for it lots of times when the sky has been good and I've been using my 12 inch dob, a suitable eyepiece and a good H-beta filter. On the 2 occasions that I have seen it, seeing the darker "bite" out of it that demarks Barnard 33 (the Horsehead) was quite possible. The Horsehead itself is not small. Even seeing the Flame Nebula can be quite challenging under a less than very dark and transparent sky and you really need to be able to see that quite obviously to have a chance of the more subtle IC 434.

Thank goodness for that ! I was starting to make a case to myself that I really need something that fits in between my 120mm and 130mm refractors ....... 🙄

Here is my report of sighting the Horsehead Nebula from my back yard a few years back. I've done it once since then, again with the 12 inch. Here is the Sky at Night magazine guidance on seeing this target: How to see the Horsehead Nebula - BBC Sky at Night Magazine IC 434, the nebulosity that the Horsehead lies in front of is itself a very challenging visual target. It is described as "a bright strip" quite often but my experience is that it is anything but bright, at least under the conditions that I normally observe under (nornally around bortle 5-ish). It is possible to see the Horsehead with a small aperture scope - there is at least one member of SGL who has seen it, or perhaps detected it is a better term, with a 100mm refractor. For me, it is probably the hardest visual target that I have managed to see in my years of observing. I love Jeremy Perez's description of this one: "Really, it's like trying to see a little bit of nothing with a little bit of less than nothing resting over it" 🙂

I've owned my Vixen ED 102mm F/6.5 refractor for longer than I've owned any other scope (16 years) because it is such a useful scope. Such an instrument can deliver really low power views of over 4 degrees in true extent one moment and then 250x high resolution views the next. It's really great for solar observing as well (suitably filtered of course). Very portable, quick to cool down, easy to mount, compact to store. It's just "win-win-win-win" with such scopes which is why they are so popular. The Vixen F/6.5's are long out of production now but there are a number of other fine alternatives available today, a number of which have already been mentioned in this thread 🙂

Polaris is useful if your mount does not track.

My preferred approach is on the right of this pic 🙂 I still use the Baader zoom, just not with a barlow. The Svbony 3-8 zoom cost only a few £'s more than the zoom barlow.

Yes, it will look like the scope is out of collimation. It may well be OK though, if it didn't land on or hit anything too hard.

Lucky there was a plant pot down there ! Hope all is well with the diagonal. My lovely Vixen ED102 refractor fell of the mount onto concrete a few years back ! Luckily the damage was restricted to the diagonal and dew shield both of which were fixed. Scopes hitting hard surfaces make a horrible noise though, as do their owners a few seconds later 😬

Nice to see the pics and reports on this. I ended up going out for family a meal and then to the cinema so I've only just been able to get a scope out. Just 2 moons in a line now with Io having gone into hiding 🙄 Nice details in the NEB though.

I have one of those on my 130 TMB/LZOS F/9.2. Lovely focuser 👍 Having looked at the new listing I can't believe the price they have reached though 😬

It might be clearish here if the forecasts are correct. Thanks for the heads up - I'll take a look later 🙂

Similarly, some of my best views of Jupiter have come when observing it against a sky with plenty of light left in it.

Do you get double images of stars as well ? Is the effect showing at high and lower magnifications, or just high ? The fact that they rotate one way and then the other as you travel through focus and back again must be a clue I guess ? Sorry that you have not had a response in 48 hours - it's not an issue that I have encountered with my dobs to be honest with you.