ED120 Upgrade enquiry

[Hex]

The ED 120 is a meer 20mm larger than my current frac, would the upgrade by meaningfully noticeable? Subjective I know.

[Bizibilder]

I assume from you kit list in your signature that you are a visual observer - then aparture rules! For the money, however, you may be better off goung for a reflector where you really will notice the difference that a really large aparture can make. If you are an imager then the 120 is a "faster" f/7.5 scope than the 100 f/9 and you would certainly notice the difference.

[Hex]

For the money, however, you may be better off goung for a reflector where you really will notice the difference that a really large aparture can make

I bought a Newton a while back and sold it 3 weeks later and bought another refractor for a variety of reasons, star spikes and coma mostly. Some nights I can really see the difference and the benefits a large Newton would so obviously bring, on other nights all I can see are poor mushy views. The aperture thing leaves me often confused. When I was a kid the accepted view was a 4 inch refractor produced the same views as a 8 inch Newtonian. I read this in the books of the time and recently saw this clip from 87 from the sky at night by Mr Moore who again claimed that a 3 inch frac and a 6 inch newt were roughly on a par.

My own eyes tell me this is true The Ring and Dumbell Nebula's look the same to me in my frac as the they do in an 200P, M42 and M32 are just the same, the only difference I can tell is the quality of the view. Its only once I look through scopes around 12 inches that I begin to get the WOW factor, and I genuinely do not have the space in my little cottage for one. I know what the maths say, I also know what they say about the prospects of flight for bumble bees

[alan potts]

Hex,

Funny thing I remember the same words in books from 35 years back and can remember Patrick Moore saying the exact same thing. But when it comes to magnitude the 6 inch can see fainter stars so they are not the same.

Alan.

[Bizibilder]

I don't think you can make those comparisons nowadays as things have moved on a long way in terms of surface/transmission coatings - both for mirrors and lenses etc. Plus the quality of our optics is almost certainly better than the "normal" amateur kit that was available then (of course, there always has been a small "premium" market - with its associated very high prices!).

[nightfisher]

Carl, how dark are your skies at your home location? your 102 would perform better from a darker location than a 120 in a more light polluted one, if you see what i mean, are you able to travel a little way to a darker sky

[Hex]

Carl, how dark are your skies at your home location? your 102 would perform better from a darker location than a 120 in a more light polluted one, if you see what i mean, are you able to travel a little way to a darker sky

Skies are not too bad Jules really. I can see the Milky way from my garden if its dark enough, The star fields through Cygnus are just mind blowing at the minute.

[A McEwan]

I followed that upgrade path and found that there WAS a noticeable difference in what could be seen. I'd say go for it.

Ant

[jam1e1]

also followed that, went from 100ed to 120ed (still own 120ed) - technically around that apeture the improvement is roughly linear. In reality, as per Ants note also noticed a difference, whilst not massive depending on what looking at it does give a subtle improvement on globular clusters. Visually, The return you get per £ spent on 2nd hand scopes is, IMO, worth it. Personally wouldnt say the same for a SW120ed to 150ed esprit frac jump (although this is not quite apples for apples as doublet vs triplet).

For info there is discussion on another forum about APM producing a 150ed doublet - have considered an upgrade, potentially, when its produced but cost would still be relatively high, will wait to see specs and writeups when comes out (apparently circa end of this year)

Another option im considering at the moment is buying a TV parcorr for 10" to get a 'value for money apeture/sharpness' combo, but parcorr around £400ish need to consider options

[Hex]

The return you get per £ spent on 2nd hand scopes is, IMO, worth it.

I quite agree, My ED100 was £390 second hand, was 12 months old and in perfect condition. I'm however hoping my new found aperture fever will wear off soon, its not just a scope, I would have to buy a SKYTEE or GIRO III to mount it too.

[ollypenrice]

I think it would make a difference but a subtle one. In fact most differences between scopes are on the subtle side when you look at the enormous difference is size between big ones and small ones. What is nice in this potential upgrade is that there is little price to pay in terms of reduced FOV because of the faster F ratio of the 120.

Olly

[Hex]

In fact most differences between scopes are on the subtle side when you look at the enormous difference is size between big ones and small ones.

Very true, not something you expect when you first start comparing scopes is it.

[John]

I followed that upgrade path and found that there WAS a noticeable difference in what could be seen. I'd say go for it.

Ant

Me too. I've now got an ED102 (Vixen) and an ED120. Both are great scopes but the 120 definitely shows noticeably more planetary detail and better views of fainter deep sky objects. I'm keeping the 102 because it's so portable (F/6.5) and rather rare !.

I've been looking at upgrade paths lately, refractor-wise, beyond the ED120 but things quickly get darned expensive and darned hard to mount so I'm reaching the conclusion that the ED120 is perhaps the optimum one for me

[Hex]

I think its widely accepted that the AZ4 is nearly, but not quite man enough for an ED120. This a real shame for me as I really like this mount, perfect for the ED100, uber solid. Its a Giro III you use isn't it John with your ED120?

[nightfisher]

just a suggestion, how about keeping the 100Ed/AZ4 set up and getting a large dobsonian, say a 200 or 250.............best of both worlds...........................i`ll get me coat!!

[John]

....Its a Giro III you use isn't it John with your ED120?

Well, a Giro type mount made by a UK Engineering firm called Ambermille based in Norfolk. I don't think it's produced now though. The ED120 is really steady on it. The AZ-4 is enough for a short session up to 150x or so but the ED120 will go up to 250x on the right targets and the AZ-4 is just not stable enough for that.

For deep sky though, Jules (nightfisher) is right. I keep a 10" F/4.8 newtonian for the faint stuff - a refractor (one I can afford anyway !) just can't compete with a newt for "going deep".

[ollypenrice]

Me too. I've now got an ED102 (Vixen) and an ED120. Both are great scopes but the 120 definitely shows noticeably more planetary detail and better views of fainter deep sky objects. I'm keeping the 102 because it's so portable (F/6.5) and rather rare !.

I've been looking at upgrade paths lately, refractor-wise, beyond the ED120 but things quickly get darned expensive and darned hard to mount so I'm reaching the conclusion that the ED120 is perhaps the optimum one for me

I can understand that, John. The TEC140 is a tad better than the slightly smaller and much cheaper apos I've tried but in visual use you pay a fortune for a small gain. The TEC is fine on an EQ6 though. It isn't close to its limit even for DS imaging.

Olly

[Hex]

how about keeping the 100Ed/AZ4 set up and getting a large dobsonian, say a 200 or 250

Oh I would say its a matter of time. My son is joining the RAF next year so there will be a little more room in the cottage (The shed is as full as an egg) How I would carry a dob base down the stairs is another matter altogether My wife will go crackers

[nightfisher]

The dob takes very little room stood up right, i used to store my old Orion 150 f8 stood up beside a kitchen welsh dresser, you have decent eyepieces and a pretty good night sky, the dob would cost half the price of a 120mm ED, or less