Classic or ED Refracter for CG-4 mount?

[Chris]

I bought a beautiful 4" F15 achromat a few years ago and used it on many occasions alongside my ED120. Though the F15 was a super scope and its CA was in no way objectionable, I chose to sell it for the following reasons.

It wasnt as easy to use as the shorter ED, as the positions I had to get into could be quite uncomfortable, especially if observing near the zenith.

The longer scope was much more susceptible to the wind. Even a breeze could cause the image to tremor, so high powers were difficult to use successfully.

I felt there was no superiority that the F15 had over the F7.5 ED, plus the ED had the added advantage of offering a wider field of view at low powers.

To do the longer achromat justice it really needed to be mounted on a substantial equatorial, ideally with a Hargreaves Strut attached. This would make the scope far less easy to set up and therefore less likely to be used.

A small apo of up to 4" is a joy to use by comparison. The ease of setting such an instrument up means you'd be more likely to nip out and observe more often. Also, the comfort factor has a major part to play in effective observing. The more comfortable you are at the eyepiece, the better you'll be able to concentrate and the more you'll see.

Mike

Good post Mike

You're a brave man, your 4" f/15 must have been huge! I had the chance of a nice 76mm f/15 but decided against it due to size, it did look very majestic though.

I did previously have a nice little 60mm f/15, apart from it's flimsy mount I found the 1000mm FL fine, it was a charming little scope that just made me feel good using it. I think the flimsy eq1 style mount let it down else you never know I might have kept it. 

I do think a good observing chair is a must with a long frac.

[Chris]

I see the TAL has gone.

good luck with the carton 60mm, post some pics when you get it

Thanks Jules, I'll take some pics when I've got it set up for white light

I wonder who got the Tal?? 

[Chris]

There is a Skywatcher ED100 on ab&s at the moment.

http://www.astrobuysell.com/uk/propview.php?view=97227

Is that a good price? pay an extra 200 and you can get a new one with a 2" diagonal, 2" EP, 50mm finder, and dedicated SW reducer. If these things are included it would be a good buy but they aren't listed.

[Skyline]

That's a point, even when the reducer is used the colour correction on the scope is still very good, regardless what people may say 'the scope being too slow' on the brighter DSO's they perform quite well. The C100ED s/h do not stay around for long when they are advertised as you may know

[mikeDnight]

Good post Mike

You're a brave man, your 4" f/15 must have been huge! I had the chance of a nice 76mm f/15 but decided against it due to size, it did look very majestic though.

I did previously have a nice little 60mm f/15, apart from it's flimsy mount I found the 1000mm FL fine, it was a charming little scope that just made me feel good using it. I think the flimsy eq1 style mount let it down else you never know I might have kept it. 

I do think a good observing chair is a must with a long frac.

Hi Chris.

I often prefer to sit comfortably at the eyepiece just turning the diagonal to whatever angle is required. Its easy for me to do that, as the arc my scope makes from zenith to horizon is probably less than 24". It can become a bit more difficult with longer refractors, but there are several different designs for observing seats floating around.

The 60mm you've just bought shouldn't pause much of a problem as far as comfortable observing goes and I'm sure it will give you some really nice views, especially of the moon. Back in the 1980s Peter Grego published some really nice sketches of lunar features in an SPA journal or circular. They were quite inspirational, showing a small scope such as a 60mm refractor is far from a toy, and can be used as quite a serious instrument.

I think the biggest problem by far with such small refractors, was that they were supplied with some pretty awful eyepieces. With a modern plossl they'd give some really pleasant views I'm sure.

I hope you have a really great time with it. It certainly looks a lovely instrument.

Mike :-)

[Stu]

Biggest problem I have with small fracs (60mm) at high mags is the exit pupil. This causes floaters in my eyes to become very pronounced. But then I am talking about mags of over x120, up to there is fine.

[Chris]

Thanks Mike, another good post  

I have a 10mm BCO on the way which should work quite well at 100x, plus a few Plossls 12,15, and 25mm. My 6mm Vixen SLV might be pushing things other than the Moon and Sun.

I'm not even sure I have a 1.25" diagonal?   I'd better go and check!. 

[Chris]

Biggest problem I have with small fracs (60mm) at high mags is the exit pupil. This causes floaters in my eyes to become very pronounced. But then I am talking about mags of over x120, up to there is fine.

This is a good point, I do suffer floaters with an exit pupil approaching 1mm, I'll try pushing things with my 6mm SLV just out of curiosity, but will probably be sticking to around 100x or less

[Roy Challen]

So, no one in thread wants the Zeiss on abs then? 63mm aperture not enough? Cool, I'll have it....(wakes up, realises it was only a dream)!

[Stu]

So, no one in thread wants the Zeiss on abs then? 63mm aperture not enough? Cool, I'll have it....(wakes up, realises it was only a dream)!

Sure it's lovely Roy, very tempting but I'm trying not buy anything for a while!!

[Chris]

So, no one in thread wants the Zeiss on abs then? 63mm aperture not enough? Cool, I'll have it....(wakes up, realises it was only a dream)!

That's a coincidence, I had a dream that I bought a small frac too! oh, wait a minute.

[philj]

Don't go for the vintage, it will disappoint you, same with the 60 mm just not enough aperture, best would be 100ED or. Tal 100rs

ooooh fighting talk there Jules    Sfunny I thought a Tal might crop up  

I have apos and long focus achros. For decent planetary views some aperture will help, e.g. 4". OK I have been bowled over by some views in a 60mm Swift on planets but with 60mm you are limited in magnification. A 60 decent 60 is also good on lunar and solar but again mag is limited.

So that leaves Apos or long focus achros. I have both and love the views through both. I use an F15 4" achro regularly and I am sometimes blown away by the planetary views but one of these would not be good on your CG4. Yes it works, I have used the F15 on my HEQ5 occasionally but its undermounted. Below F15 CA will start to creep in, yes even on a TAL    but the amount depends on the quality of the objective.

So that leaves Apos, Ive used short focus fluorite triplets which give stonking planetary views but require silly eyepieces to get decent image scale but my weopon of choice is now a 5" ED Triplet. This may be a bit too heavy for your mount but the 115mm EDTs are a bit smaller and I can vouch for the views through some of them.

So in a nutshell I would recommend

1. try and get a look through the scopes so YOU know what to expect from them. You can have all the advice in the world from as many people as you can find but you cant beat practical experience. After all we are all different and so is our eyesight.
2. Something like a 115 EDT

Ooops just re read the last few threads I see you've gone for the Skylight 60 with Carton objective, a nice scope which will give quality views but will be a bit limited. I am still amazed at what can be seen with a quality 60mm but so long as you know its limitations you wont be disappointed. Look forward to seeing the pics

[F15Rules]

A great thread Chris and some really interesting responses - with a variety of views as ever.

I didn't post up til now since the Kenko you mentioned is mine, but a couple of things have been said that I would like to respond to.

1. I can't imagine anyone being disappointed looking through a high quality Kenko Japan 76.2mm lens! They serve up amazingly sharp, colour free stellar images with classic central dot and diffraction rings.

2. As a long scope they do need to be well mounted and the original mount, while very well engineered and of good quality, is overwhelmed by such a long scope. A CG4 is NOT sufficient. An EQ5/CG5 (preferably with an ADM puck/saddle upgrade) is the minimum to handle the length of the scope and to allow it to be used a high powers - that's what it excels at! - It's like comparing a long distance runner (the F15) with a sprinter (short focus Apo) - they are both great at what they do, but different.

3.If you have the seat, right mount (and tripod, with extension if need be), a long frac is as comfortable to use as any other scope.

4. The Carton 60mm should not be underestimated - and IMHO looks SO much better to look at than any stubby APO (he ducks..)

Finally, Chris, with your other scope being larger aperture, I think you will have great fun with your new Carton/Skylight - enjoy!

Dave

[Moonshane]

I have other scopes and generally prefer newts but wanted a refractor for white light observing. If I am buying a scope for on thing I do like it to be multi-purpose and therefore needed something that would perform well at night. I see refractors in my light polluted garden as mainly solar system and double star scopes. CA really bothers me. It even did on the moon and Jupiter in my old 80mm f11 Vixen.

Therefore I had a choice really between 80mm, 100mm and 120mm ED. I went in the end for the 120mm ED as it was the same focal length as the Vixen, yet provided the same aperture as my old 120mm F5 SW frac which was great on the sun and wide field but not on much else in the solar system.

Hopefully you'll love your new scope but I fear the reduced aperture will tell, especially on the sun.

[nightfisher]

ooooh fighting talk there Jules    Sfunny I thought a Tal might crop up  

I have apos and long focus achros. For decent planetary views some aperture will help, e.g. 4". OK I have been bowled over by some views in a 60mm Swift on planets but with 60mm you are limited in magnification. A 60 decent 60 is also good on lunar and solar but again mag is limited.

So that leaves Apos or long focus achros. I have both and love the views through both. I use an F15 4" achro regularly and I am sometimes blown away by the planetary views but one of these would not be good on your CG4. Yes it works, I have used the F15 on my HEQ5 occasionally but its undermounted. Below F15 CA will start to creep in, yes even on a TAL    but the amount depends on the quality of the objective.

So that leaves Apos, Ive used short focus fluorite triplets which give stonking planetary views but require silly eyepieces to get decent image scale but my weopon of choice is now a 5" ED Triplet. This may be a bit too heavy for your mount but the 115mm EDTs are a bit smaller and I can vouch for the views through some of them.

So in a nutshell I would recommend

1. try and get a look through the scopes so YOU know what to expect from them. You can have all the advice in the world from as many people as you can find but you cant beat practical experience. After all we are all different and so is our eyesight.
2. Something like a 115 EDT

Ooops just re read the last few threads I see you've gone for the Skylight 60 with Carton objective, a nice scope which will give quality views but will be a bit limited. I am still amazed at what can be seen with a quality 60mm but so long as you know its limitations you wont be disappointed. Look forward to seeing the pics

I have a TAL........whats CA?

A great thread Chris and some really interesting responses - with a variety of views as ever.

I didn't post up til now since the Kenko you mentioned is mine, but a couple of things have been said that I would like to respond to.

1. I can't imagine anyone being disappointed looking through a high quality Kenko Japan 76.2mm lens! They serve up amazingly sharp, colour free stellar images with classic central dot and diffraction rings.

2. As a long scope they do need to be well mounted and the original mount, while very well engineered and of good quality, is overwhelmed by such a long scope. A CG4 is NOT sufficient. An EQ5/CG5 (preferably with an ADM puck/saddle upgrade) is the minimum to handle the length of the scope and to allow it to be used a high powers - that's what it excels at! - It's like comparing a long distance runner (the F15) with a sprinter (short focus Apo) - they are both great at what they do, but different.

3.If you have the seat, right mount (and tripod, with extension if need be), a long frac is as comfortable to use as any other scope.

4. The Carton 60mm should not be underestimated - and IMHO looks SO much better to look at than any stubby APO (he ducks..)

Finally, Chris, with your other scope being larger aperture, I think you will have great fun with your new Carton/Skylight - enjoy!

Dave

I have owned 2 different Kenko 76mm  f16`s one nice one and one superb mint one, they can give nice views if you knock the draw tube baffles out, concert them to 1.25 eyepiece, but they still wont match the view of a more modern scope

[Roy Challen]

Sure it's lovely Roy, very tempting but I'm trying not buy anything for a while!!

Well, it seems like a week in this hobby is a long time, especially if it's cloudy! Dunno 'bout anyone else, but I get the urge to buy something to sate my astro fix if it's been cloudy for more than week, which it has here in Watford. Although I did get the Tal and Lunt out for half an hour yesterday morning.

[Roy Challen]

I have a TAL........whats CA?

I have owned 2 different Kenko 76mm  f16`s one nice one and one superb mint one, they can give nice views if you knock the draw tube baffles out, concert them to 1.25 eyepiece, but they still wont match the view of a more modern scope

Ahh, but surely thats the point? An ED100 (f/10 or otherwise) has got to be better than a Tal 100 with regards to CA, I'm guessing because I haven't looked through an ED100 (did have an ED70 though which was fantastic), but that doesn't stop us being fans of the Tal or even longer focus fracs. We don't buy them to compete with modern scopes, we buy them 'cos we like them!

[F15Rules]

I have a TAL........whats CA?

I have owned 2 different Kenko 76mm  f16`s one nice one and one superb mint one, they can give nice views if you knock the draw tube baffles out, concert them to 1.25 eyepiece, but they still wont match the view of a more modern scope

Sorry Jules, I can't agree with you there. A great lens is a great lens, whenever it was made, or whoever it was made by.. think Cooke or Alvan Clarke for instance??  

My Kenko doesn't have draw tube baffles, never did. The Towa Topic (Meade 339) 80mm F15 did have them, and they did need removing, but not the Kenko to the best of my knowledge. And the views match any ED100 or Tal F10/Lyra F11 for sharpness and image quality (obviously at 23mm less aperture than the latter, it can't resolve so much or reach as deep.

The Kenko also accepts a Vixen type threaded adapter to allow 1.25" eyepieces - I've even used a couple of 2" eyepieces using an Agena Blue Fireball reverse 2" to 1.25" adapter with limited vignetting

The one area where these old scopes do lag behind I think is the finderscopes - although perfectly useable they do have a narrow field compared to the modern Synta type 8x50s etc. Gernerally, on the good Japanese vintage scopes like Kenko,Royal Astro, Nihon Seiko (Unitron), Swift, Yamamoto, Vixen etc, the engineering is streets ahead of the Chinese scopes - and they just couldn't make them like that nowadays for a price people would pay. A Unitron/Polarex 4" F15 if available new now would cost probably £2K plus, which would be nonsense when you could buy a much bigger Chinese scope so much cheaper.

You pays your money and you takes your choice..

Dave

[Chris]

A great thread Chris and some really interesting responses - with a variety of views as ever.

I didn't post up til now since the Kenko you mentioned is mine, but a couple of things have been said that I would like to respond to.

1. I can't imagine anyone being disappointed looking through a high quality Kenko Japan 76.2mm lens! They serve up amazingly sharp, colour free stellar images with classic central dot and diffraction rings.

2. As a long scope they do need to be well mounted and the original mount, while very well engineered and of good quality, is overwhelmed by such a long scope. A CG4 is NOT sufficient. An EQ5/CG5 (preferably with an ADM puck/saddle upgrade) is the minimum to handle the length of the scope and to allow it to be used a high powers - that's what it excels at! - It's like comparing a long distance runner (the F15) with a sprinter (short focus Apo) - they are both great at what they do, but different.

3.If you have the seat, right mount (and tripod, with extension if need be), a long frac is as comfortable to use as any other scope.

4. The Carton 60mm should not be underestimated - and IMHO looks SO much better to look at than any stubby APO (he ducks..)

Finally, Chris, with your other scope being larger aperture, I think you will have great fun with your new Carton/Skylight - enjoy!

Dave

Thank you Dave All I know is the Japanese know how to make a lens, now and historically. I think your right about the mounting of your 76mm, my mount is basically an EQ3 with steel legs and I think the 60mm is probably a better size for it.

I've read quite a few positive things about the Carlton lens but I'm still aware it's only 60mm of aperture. Like you say Dave, I Do have a C8 for a bit of aperture and some massive good quality bins, I'm sure I'll enjoy this scope but if I don't I'll be as honest as I can be for the sake of anyone in future reading up on the subject

[Chris]

I have other scopes and generally prefer newts but wanted a refractor for white light observing. If I am buying a scope for on thing I do like it to be multi-purpose and therefore needed something that would perform well at night. I see refractors in my light polluted garden as mainly solar system and double star scopes. CA really bothers me. It even did on the moon and Jupiter in my old 80mm f11 Vixen.

Therefore I had a choice really between 80mm, 100mm and 120mm ED. I went in the end for the 120mm ED as it was the same focal length as the Vixen, yet provided the same aperture as my old 120mm F5 SW frac which was great on the sun and wide field but not on much else in the solar system.

Hopefully you'll love your new scope but I fear the reduced aperture will tell, especially on the sun.

Sounds like you made a very good logical choice Shane. I had a little taste of the Equinox version of the ED120 a while back and it's lovely scope, pretty close to an allrounder if there is such a thing? I place it between my old C8 and my new C8 Edge on planetary performance (my turn to duck )

I think I should report back after using the Skylight for a while. I know its difficult to be objective when you have chosen to buy a scope, but I'll try my best to be honest for the the good of anyone in future thinking of a similar purchase.

Hopefully it will go nicely with my other kit, but I'm also going to keep my eyes peeled for an ED100. Without trying to sounds too cheesy, the ED100 is a choice with my head and the Skylight is one with my heart. Ok, that sounded cheesy 

[russ.will]

I thought my ears were burning! 

I've not had much luck with getting a decent first light with the C100ED-R, but having owned a couple of short 80ED/Apos and an AR-127L, I have to say; Dang! This thing is colour free. 

That's the good.

I did buy it with the intention of binning the stock focuser, but that won't stop me from pointing out just how agricultural the R&P version of this scope is. If this was the budget state of the art, no wonder Crayfords gained popularity, that's all I can say. I have tweaked with some Teflon tape and and cleaned the tar off it, but even so it's a bare minimum of acceptable with a smoothness of action akin to rolling gravel. The TS Monorail can't come soon enough....

The other thing that struck me was that contrast wise, it was a really poor second to my ES80 Triplet. Lunar views were very sharp, but a bit flat and uninteresting, lacking any real pop. Side-by-side on the iOptron, (ES100 9mm in the 80ED and 20mm in the C100) it wasn't exactly a difference you had to go looking for.

I resorted to testing and tweaking in daylight. Behind me, there is a tall, matt black metal chimney stack, with a 'chinese hat' cowl. Silhouetted against the mid afternoon sky, it's CA nightmare with hard edges and deep shadow detail offering almost the polar opposite of lunar viewing. The C100 was and I hate to use such definitive terms, rubbish. I get better contrast out of my 30 year old 20x50 Russkie spotter and I did check.

Yanking the EP and diagonal out and looking straight up the tube showed where some issues lay. The inside of the OTA between the the lens cell and the first baffle can be seem as a clear and wide ring of bright grey, even with the focuser racked out. It's like the first baffle is way too small. By comparison, the ribbed surface of the lens cell behind the lens elements, which looks shiny when viewed from the front, looks plenty dark, so the micro baffles seem to work well.

30 minutes later, I'd flocked the area ahead of the first baffle and the inside of the somewhat shiny dew shield for good measure - that wasn't visible from the focuser, but in for a penny.... Back outside I now noticed a clear ring of bright spots around the outside of the baffles, between the points where they're fixed to the inside of the OTA. The flocking appeared to have masked the issue of the foremost baffle, so using some black barn paint (thick, sticky and doesn't run) I used the end of a stick to dab the paint into rear of each offending hole. It dries very quick, so less than half an hour later, I was finally set up pointing at said chimney.

What a difference. I could now see texture in the black soot, in the shadow on the underside of the cowl, whilst the whole subject was being strongly illuminated from behind by a very bright, hazy sky. It's been way too cloudy and windy since to test at night since. 

Now, I realise that one has to forgive a lot of these scopes in mechanical terms, because of the optics they deliver for the price, but I'd be somewhat miffed if I paid RRP for a new scope, that was showing these really basic deficiencies. I presume the SW ED100s don't suffer the same way, but I'll let others comment and the stock SW dual speed Crayford will certainly be a pardigm shift over the R&P. However, as the Synta ED100s are a desperately unfashionable F9, the second hand price does a lot to off-set that. I paid £200 for mine in very clean condition and even if you reckon on £350 inc replacement focuser, it's still hilarious value for money with an hour of time and £10 worth of improvements on top.

It's light enough and short enough that a breeze doesn't bother it on the Minitower and as I have the larger, taller tripod for that, the EP doesn't reach any really silly positions. Mind you 1kg EPs help move it up the tube rings somewhat, but even with the TV Plossls, it's not bad at all.

Hang in there for the right one at the right price, because it'll be a happy partner for a CG4.

Russell

[John]

Celestron picked a poor R&P design for their versions of the Synta ED 80 and 100. Different tube size too for the 80, for some reason. The Skywatcher ED100 that I had many years back (blue tube days) had a servicable single speed crayford although it needed the flat bit flattening a bit more as they often do. The Orion Optics OC1 crayford has the same flaw as do the Crawmach, William Optics and many others I've used - I think you have commented in the past Russell that machining a flat surface can't be that hard !

I think I've seen the C100 ED's used for around £200 as well though so probably worth mucking about with a bit at that sort of price.

Interestingly, the Meade 102ED, marketed in 2000, was an ED doublet with the same F/9 spec but a lower cost FPL-51 ED element and listed at £1,599 as an optical tube in a TH brochure I've got from that era. I think that had a crummy focusser as well. Poor objective cell too and dodgy objectives in quite a few as well from the reports on them  .

[russ.will]

I'm not sure how much difference FLP-51 would actually make at F9 - I'd  rather a well figured lens than one just made from exotic glass for the sake of it - but you're absolutely right, some of the stuff that makes it onto these scopes from ALL of the big optical houses is amazing and dressing up an focuser from a cheap achro with a 10:1 knob for the ED variant isn't fooling anybody!

Yes, I've commented on the Synta tune up that requires you to grind your own focuser, but my WO Zenithstar was equally amazing because it actually had a well machined flat (other examples may vary!) but WO anodized it into something more slippery than soap. The other thing I find amazing is how close short the bearing surface opposite the focuser is on a lot of scopes, leaving them incapable of resisting focuser droop with even moderate loads. This isn't even asking for additional components, just looking at the ones that are there with an engineers eye.

Still, enough people will buy them new that there is a healthy, cheap second hand supply worthy of fettling and you can't knock something like an Evostar 80ED DS-Pro because it's practically second hand money anyway! Mind you, when you look at something like an Altair Lightwave 80 F6 ED with it's 8-bearing R&P focuser, CNC tube rings and ali case for less than the cost of the focuser upgrade the Evostar will want, you could even question that.

What we are, is rich in choice to do it right, or in affordable bite sized chunks. That's cool.

Russell

[John]

I'm not sure how much difference FLP-51 would actually make at F9 - I'd  rather a well figured lens than one just made from exotic glass for the sake of it .....

I agree Russell. My Vixen ED102SS is an F/6.5 and uses an FPL-51 element but it's colour and spherical abberration correction is as good as the Skywatcher F/9 100ED it replaced. The match with the non ED element and the figuring / polishing quality are probably even more important than the ED glass type chosen.

[Chris]

I thought my ears were burning! 

I've not had much luck with getting a decent first light with the C100ED-R, but having owned a couple of short 80ED/Apos and an AR-127L, I have to say; Dang! This thing is colour free. 

That's the good.

I did buy it with the intention of binning the stock focuser, but that won't stop me from pointing out just how agricultural the R&P version of this scope is. If this was the budget state of the art, no wonder Crayfords gained popularity, that's all I can say. I have tweaked with some Teflon tape and and cleaned the tar off it, but even so it's a bare minimum of acceptable with a smoothness of action akin to rolling gravel. The TS Monorail can't come soon enough....

The other thing that struck me was that contrast wise, it was a really poor second to my ES80 Triplet. Lunar views were very sharp, but a bit flat and uninteresting, lacking any real pop. Side-by-side on the iOptron, (ES100 9mm in the 80ED and 20mm in the C100) it wasn't exactly a difference you had to go looking for.

I resorted to testing and tweaking in daylight. Behind me, there is a tall, matt black metal chimney stack, with a 'chinese hat' cowl. Silhouetted against the mid afternoon sky, it's CA nightmare with hard edges and deep shadow detail offering almost the polar opposite of lunar viewing. The C100 was and I hate to use such definitive terms, rubbish. I get better contrast out of my 30 year old 20x50 Russkie spotter and I did check.

Yanking the EP and diagonal out and looking straight up the tube showed where some issues lay. The inside of the OTA between the the lens cell and the first baffle can be seem as a clear and wide ring of bright grey, even with the focuser racked out. It's like the first baffle is way too small. By comparison, the ribbed surface of the lens cell behind the lens elements, which looks shiny when viewed from the front, looks plenty dark, so the micro baffles seem to work well.

30 minutes later, I'd flocked the area ahead of the first baffle and the inside of the somewhat shiny dew shield for good measure - that wasn't visible from the focuser, but in for a penny.... Back outside I now noticed a clear ring of bright spots around the outside of the baffles, between the points where they're fixed to the inside of the OTA. The flocking appeared to have masked the issue of the foremost baffle, so using some black barn paint (thick, sticky and doesn't run) I used the end of a stick to dab the paint into rear of each offending hole. It dries very quick, so less than half an hour later, I was finally set up pointing at said chimney.

What a difference. I could now see texture in the black soot, in the shadow on the underside of the cowl, whilst the whole subject was being strongly illuminated from behind by a very bright, hazy sky. It's been way too cloudy and windy since to test at night since. 

Now, I realise that one has to forgive a lot of these scopes in mechanical terms, because of the optics they deliver for the price, but I'd be somewhat miffed if I paid RRP for a new scope, that was showing these really basic deficiencies. I presume the SW ED100s don't suffer the same way, but I'll let others comment and the stock SW dual speed Crayford will certainly be a pardigm shift over the R&P. However, as the Synta ED100s are a desperately unfashionable F9, the second hand price does a lot to off-set that. I paid £200 for mine in very clean condition and even if you reckon on £350 inc replacement focuser, it's still hilarious value for money with an hour of time and £10 worth of improvements on top.

It's light enough and short enough that a breeze doesn't bother it on the Minitower and as I have the larger, taller tripod for that, the EP doesn't reach any really silly positions. Mind you 1kg EPs help move it up the tube rings somewhat, but even with the TV Plossls, it's not bad at all.

Hang in there for the right one at the right price, because it'll be a happy partner for a CG4.

Russell

Hi Russ, I really enjoyed reading your post, and congrats on getting such a bargain!

I'm pleased to say I bagged a C100ED on ABS last night!   I did pay a bit more, 270 shipped, it does look mint though.

I have an unopened roll of flock and some mat black paint on standby, I appreciate the heads up on that I'll see what I can do with the focuser but might go down a similar route as your good self.

Now, I've got to think of a way to store 2 long scopes in the obsy? I could get two long plastic storage boxes and ad foam and desiccant perhaps