I want one! Starwave ASCENT 102ED F11

[DirkSteele]

7 minutes ago, Lockie said:

60 minutes for a 4" refractor can't be right surely? If true it's sad news. Reasonable cool down time and the ability to cut through poor seeing are two of the great things about this class of telescope that make them so suitable for the UK climate. 

I wonder what the cool down reports are like for the f/7 variant? 

 

I think there is an interesting and deeper topic on this point based on a lot of assessments I have read about cool down times for the same model of scope.  It would seem one person's cool down time is barely there for another in their own personal assessments (and that is before one considers temp differentials from house to observing location, declining ambient temps etc).

[AdeKing]

On 16/01/2019 at 16:28, Mark at Beaufort said:

the thought of a 4" ED which can be adjusted to take binoviewers does sound appealing.

I'm very interested in this scope for this reason alone, but like @Fozzie I have the Starwave Classic f/11 (which I love) and have acquired a Gold ED120 already this year so I won't be getting one for quite a while.

The cool down times are an interesting and slightly worrying development as the Starwave Classic f/11 takes next to no time to cool down. 

But maybe @DirkSteele is right and cool down assessments are a personal opinion just like what constitutes unacceptable CA in as much as what is totally unacceptable to one is completely fine for another.

Well let's hope so anyway. 

[John]

1 hour ago, DirkSteele said:

I think there is an interesting and deeper topic on this point based on a lot of assessments I have read about cool down times for the same model of scope.  It would seem one person's cool down time is barely there for another in their own personal assessments (and that is before one considers temp differentials from house to observing location, declining ambient temps etc).

I agree Matthew. When you read reports there are often one-off issues that a particular user reports that are not consistent with other reports and I put those down to the particular circumstances and preferences of that person. I was a little surprised to read of this long cool down time in more than one report and from different owners though. Having owned quite a few 100-102mm doublets over the years (ED, Fluorite and achromat) I've not come across one that needed more than, 30-40 minutes for complete cool down. But then again I live in a temperate climate where the outside temperature that I observe in is rarely lower than -5 or higher than 22c or thereabouts.

I've found that the SA (spherical abberration) is what takes time to acclimatise rather than the colour correction. Many of the reports and threads on refractors are over obsessed with CA and glass types IMHO rather than how well the objective is figured and polished. Of the scopes that I have owned, it was those that were afflicted by SA (even when cooled) that were the worst performers.

Even my 130mm tripet only seems to need around 45 minutes to fully cool.

The plus points of slow doublets should be their quick cooling time I think and also that it should be relatively easy for the optical manufacturer to get the figure of a slow objective right. 

 

[alan potts]

3 minutes ago, John said:

I agree Matthew. When you read reports there are often one-off issues that a particular user reports that are not consistent with other reports and I put those down to the particular circumstances and preferences of that person. I was a little surprised to read of this long cool down time in more than one report and from different owners though. Having owned quite a few 100-102mm doublets over the years (ED, Fluorite and achromat) I've not come across one that needed more than, 30-40 minutes for complete cool down. But then again I live in a temperate climate where the outside temperature that I observe in is rarely lower than -5 or higher than 22c or thereabouts.

Even my 130mm tripet only seems to need around 45 minutes to fully cool.

One of the plus points of slow doublets should be their quick cooling time I think.

 

One of the things I find John with living out here is some times in the year temperatures can drop very fast after the say the sun goes down after being out most the day, even though all my gear is kept outside. Also I find a battle going on, where I keep them can be colder than outside, so at first you can get a warm situation, then the temperature can drop and actually help out.

alan

[John]

This is from Altairs "Blurb" for the scope:

...The convenience of a refractor. This is the perfect scope to take out and just observe with. It cools down fast thanks to the aluminium tube and long focal length doublet objective design....

While it's not as exotic as the ED F/11, I keep thinking of my old bluetube Skywatcher ED100 F/9 - the 1st release of the ED100 design in the UK. Very light, very quick to cool, very CA free (FPL-53 element) and just £300 for the OTA in used but practically mint condition 

 

[Seafury]

Hi, I was thinking of selling my existing scopes,the Bresser 127AR and the Lyra Optics 102 and buying this scope,am I being silly or would it be a better scope?any thoughts please

 

cheers Gordon

[GlenM]

Gordon, don't sell the Lyra?

 

Glen.

 

 

 

[AdeKing]

2 hours ago, Seafury said:

Hi, I was thinking of selling my existing scopes,the Bresser 127AR and the Lyra Optics 102 and buying this scope,am I being silly or would it be a better scope?any thoughts please

 

cheers Gordon

I have the Altair Starwave Classic 102 f/11 (the same as the Lyra) and have contemplated selling it, but I figured that the Classic f/11 was pretty well corrected and all I'd really be gaining is the ability to use Binoviewers without a Barlow. 

The latter is a big draw for me but not big enough for me to sell the Classic f/11 and buy new. 

I might give it a go in a couple of years if one shows up used and some more reviews show up that are favourable. 

Ade

Edited April 28, 2019 by AdeKing

[GlenM]

If I was still in business I would certainly stock the new F/11 ED but with the new rack and pinion focuser. Heard great things about this scope. I understand your demise though.

 

Glen.

 

 

[Seafury]

Hi thanks for thoughts so far, does the extra size of the Bresser outweigh the better quality of the ED scope?

[johninderby]

See there is a Lyra 102 f11 on ABS at the moment for 300 quid.

 

[Seafury]

23 hours ago, GlenM said:

Gordon, don't sell the Lyra?

 

Glen.

 

 

 

 

 

23 hours ago, GlenM said:

Gordon, don't sell the Lyra?

 

Glen.

 

 

 

Hi Glen, is not the Starwave the same scope as the Lyra but with a better lens?

Edited April 29, 2019 by Seafury

[John]

On 28/04/2019 at 17:23, Seafury said:

Hi thanks for thoughts so far, does the extra size of the Bresser outweigh the better quality of the ED scope?

I've owned a Bresser 127L (a good one from a few years back) and an ED100. Despite showing some CA (as you would expect from the focal ratio), I was quite impressed by the performance of the 127L - my first proper 5 inch refractor. The downside is that the optical quality of the chinese 127mm F/9.3's is a bit variable - I also had one branded Meade which was really not that good no matter how I tweaked the collimation. My bet is that the ED100's (and the 102 F/11's) are quite a bit more consistent optically.

Now if we introduce an ED120 into the frame, although not possessing that big F number, the practicality and performance surpass the 127mm F/9.3 chinese achromats and the 100mm ED F9's and even the F/11's I reckon.

 

[GlenM]

22 hours ago, Seafury said:

 

 

Hi Glen, is not the Starwave the same scope as the Lyra but with a better lens?

Probably made by Kunming in China. I'm assuming the only difference is the use of ED glass. Another assumption would be they are using FK61 (similar refractive index to FPL51) ED glass for this new scope. I've not looked through the new scope, but I have looked through other FK61 scopes and I've not been impressed, although the focal length should help with this. That was some years ago. I know the figure and polish of the F/11 Achro has always been pretty good. I still don't know why they use a twin speed focuser though because at F11 the depth of focus is quite broad and you just complicate matters if something goes wrong with the fine focus. These can be tricky to get right.

 

Glen.

 

 

[Seafury]

Hi Glen and John thank you for your thoughts,I still need someone to write a note for my wife to tell her I must have one