RobertI

Great vid as always Chris. Very informative. Exit pupil is a weird concept but you explained it really well. I think it’s hard for many people to understand that exit pupil is unaffected by the FOV of the eyepiece; so a 6mm Plossl with 50 degree FOV will produce the same diameter exit pupil as a 6mm Explore Scientific with twice the FOV. Counter-intuitive! 🙂

Stunning. A wonderful four minutes. Thanks for sharing.

What an interesting looking scope, first time I’ve seen this. Looks like it can be used for narrowband DSO observing and imaging with the right filters, and even without filters the coating acts like a UHC filter? I guess that what tri-band alludes to? Sorry I’m a bit behind with all the latest tech! 🤓

Nice little session there. Yes the stars are very crisp and clean through my 66mm too, very refractor like I guess. I did notice at high mags the stars become noticable discs due to the small aperture, but still perfect. It has good splitting abilities as I found out in a previous session :

You may also be interested in this post of an EAA session with a 60mm achro finder and Ha filter - I would think the ZS66 would be even better -

This is the only relevant thread I could find - note the M31 image was 5 second exposures: The intention was to use it for Ha on larger nebs - I can’t recall if I ever did but I think that would be it’s real strength, as I used a 60mm finder for Ha and found it surprisingly good.

I’ve done this very thing in the past - I’ll see if I can dig out some of the images I obtained. 👍

Lovely little scope - I have a nice orange one (I think they did a 'Meade Blue' and a 'Celestron Orange') which I have close to hand for dashes into the garden. Very light, well made, excellent optics for visual and imaging - what's not to like? Hope you get on well together.

Nice report Victor, doubles to indeed look superb through a nice 4" apo.

Good result!

I thought I’d mention it in case you we’re wondering why there weren’t many responses! 🙂

I think the answer might depend on whether your friend is interested in planetary/lunar, deep sky or really large stuff like emission nebs? There is a useful guide to ZWO cameras for EEVA here. They seem to recommend the ASI290 or ASI224 which are in the low £200‘s but have small sensors which limit the object size and can also make finding the object a pain! Hoping other “EEVA’ers” can chip in here as I’m not up to date with current CMOS cameras. He would also need a reducer of some sort if the scope is F6 or more. Without wishing to discourage anyone, the process of aligning accurately, focussing and finding the object and then stacking using software makes this less like visual and more like imaging! Having a permanent setup can really help though. There is also the Revolution imager, which is not within budget but is a nice simple solution.

Grim news. I think is another thread about this.

Very nice looking double, thanks for the heads up. 👍

That’s just horrible. I hope it can be rebuilt.

Really entertaining stuff, thanks for the link Chris.

Hi Victor, I have a Giro-WR which is made by Berlebach and I think is pretty identical in terms of capacity and size to the Castor. It’s a real quality piece of kit and can handle the weight of a 102ED - I think on a sturdy tripod (like the 1.75” steel tripods) it could work for G&G. But one word of warning - my Giro-WR and I’m guessing the Castor has very little ‘stiction’ so it’s hard to find the right tightness on the alt knob which allows easy movement but also stops the scope spinning skywards or ground-wards at high speed and crashing into the legs. Not an issue for my short tube 66/72mm refractors but for longer heavier scopes can become a problem. When there are also heavy/long diagonals and eyepieces and you are moving around the sky it’s a real pain to get this right. I recognise that many other people are very happy with using scopes of this size on them though. The Skytee (which I know is too heavy for G&G) has the famous sticky glue grease, which provides a lot stiction which I actually like. Opinions vary as always! 😆 Edit: I have found a counterweight helps the the azimuth move more freely, even with a small scope attached - it is perfectly usable without but less free and a bit harder to position accurately. Not sure it would be so nice to use with a heavier scope without counterweight though - I’ll give it a go!

That’s a great spot John, you must be chuffed. 🙂

Fantastic report, what a night, some really interesting and varied objects there. Nice sketches too. 👍

Well done to you, writing a novel is a major undertaking, I hope you get lots of readers. Your first two reviews are glowing!

That’s a lovely little package Victor! Very portable. Looks like you have some room for additional accessories that you WILL get. 😁 I have an aluminium case for my eyepieces/filters etc, but currently no case for the 102ED-R, but I’m thinking about one of those lovely Oklop bags. TBH the only transporting I do is from the garage to the garden - all of 15 feet, so hard to justify really!

Wow Chris, that’s fantastic news for you, FLO, and all of us! Exciting stuff. 🙂

Ok quick update on this, I’ve had no interest on this despite a price drop (probably not helped by the fact that I don’t want to post, so reduced buyer base). I am now considering the forking the scope which I think it’s just a case of undoing two screws - this will allow me to post just the OTA anywhere in the UK and hopefully should be a much easier sale. Any thoughts on what the OTA may be worth?? I was thinking possibly around the £120 mark? Thanks for any help. 🙏

A lovely night last night, perfect temperature, no wind, transparent skies and excellent seeing. Had a lovely and, as usual, short session with the 102ED-R. I sat back in my observing chair and looked at my prepared list of in SkySafari. I am a recent convert to seated obsering and I find it really helps to calm things down, encourage me to take my time and think clearly. First stop was Izar (Epsilon Bootis). I've been seeing this one a lot lately in a smaller 66mm scope and it was lovely to see it easily split with the larger aperture. Just below Izar was HR5524, a lovely double separated by 2.2", very close together at x100, and at x200 revealed a blue white primary and white secondary. Now across to Xi Bootis, probably my favourite of the evening with a bright white primary and a stunning golden yellow secondary just 5.5" away. I found this was nicest at x100 with both components pin sharp like tiny ball bearings. The scope was working well tonight. On to the nearby Pi Bootis, another fine double very similar in size and brightness to Xi, but without the colour difference. Happy with my successes I thought I'd try something more challenging - Zeta Herculis, with two components of mags 2.8 and 5.4 separated by 1.5". Even at 200x I could only just make out a brightening of the first diffraction ring at the correct PA, but nothing better, not helped by scudding clouds. However I had better success with HD136176 in Corona Borealis comprising two mag 7 stars separated by 1.6". Easy to find and just split at higher mags. Finished with a quick look at the double double (both nicely split at 100x) and Alberio rising in the East. I think my doubles observing list will keep me going all year! I created it by filtering on doubles which are between 1.5" - 10" and magnitudes 2 - 8. The result was a LOT of doubles. The constellations with the most targets seemed to be Bootes, Hercules, Cygnus, Orion, Ophiucus and Taurus. It was also interesting to see that Lynx had a lot of doubles, which was surprising given that it is a very faint constellation with relatively few bright stars.

A truly amazing image. I finally worked it out. 🙂