SW ST150 or Bresser Messier AR152S/760?

[Chris M48]

I really can't make my mind up between these two refractors.

Leaning toward the Startravel because I have  SW ED100 APO and it would share a few accessories.

Does anyone have a view?

Enhanced DSO's and daytime wildlife are my aim.

Thanks.

 

[xtreemchaos]

id go for the AR152S, it should show a lot less CA with it having a correcter in the focuser, but if you are thinking of using a solar wedge like a lunt then it would be the st150 as the ar152s corrector wont work safely. goodluck , charl.

[Chris]

If from new I'd go for the bresser, if second hand something likethis just to save a bit of money:

http://ensoptical.co.uk/telescopes/skywatcher-helios-150mm-f5-refractor-

You can get them for as cheap as 220 on astrobuyandsell but the above looks like a good example and it's free delivery, or less than 6 quid for next day (I've just bought my HEQ5 from them).

A 6" f/5 achro will have loads of chromatic aberration, so not something I'd think of for daytime use, your ED100 would be tons better. Low power views of DSO's should be nice but expect lots of field curvature.

[Chris M48]

Thank you both. I notice that the finder bracket and shoe are different from the SW's and Altair Starwave which will mean changing my  finder/guider setup if I plump for the AR152s but the corrector is a serious consideration.

I was going to have 2 speed Crayford fitted if going for the StarTravel but I could get a filter for the CA instead. Or am I missing the point?

Nothing's straightforward in this hobby is it!?

[Paz]

I can't advise on comparing those two scopes but if it helps to know I use a Baader semi-apo filter with my ST120 for looking at bright targets and that combination gives a view I'm happy with. I've never used an ED or apo telescope so perhaps I don't know what I'm missing, but I have used a stopped down unobstructed ~137mm aperture with my 14" reflector that provides super-clean CA-free views and that has not stopped the ST120 getting outings.

[spaceboy]

8 minutes ago, Paz said:

 with my 14" refractor that provides super-clean CA-free views

[John]

The filters reduce the CA levels by approx 30%-50% based on the ones that I've tried. They do add a subtle (or not so subtle depending on your eyes) tint to the view and of course filtered light is light that is not making it into the final image.

I think these large, fast achromats are great deep sky / rich field scopes but are not designed to be high resolution instruments as well. They can put up pleasing views with a filter in use if planetary / lunar viewing is not your principle use for the scope.

 

 

[Chris]

@Paz you have a 14" refractor!? I'm guessing this is a typo? wow if not! If not please post up some pics on the "show me your frac" thread, pretty please  

@Chris M48 Semi apo filters do improve CA by cutting out certain wavelengths of light, but as Paz mentioned you can mask down the aperture to increase the focal ratio as an alternative. My 76mm f/16.7 achromatic refractor shows no discernible CA at all.

Your ED100 is a very well corrected scope being both ED and f/9, so I'm just a bit concerned about how you will find the CA jump from ED100 views to a Synta/Bresser 150mm f/5 achro. 

If you don't get on with the blue wash of CA then a Semi apo filter, masking, or both are your friend

[parallaxerr]

40 minutes ago, Paz said:

I use a Baader semi-apo filter with my ST120

Same here. I've been impressed with the ST120/Baader semi-apo combination and have split doubles at high mag without CA being intrusive. I'd like the ST150, but a mount upgrade would be required first.

[Paz]

29 minutes ago, Chris Lock said:

@Paz you have a 14" refractor!? I'm guessing this is a typo? wow if not! If not please post up some pics on the "show me your frac" thread, pretty please  

Oops - I wish I did but the reality is it is a typo! 

[Chris]

1 minute ago, Paz said:

Oops - I wish I did but the reality is it is a typo! 

Damn, knew it was too good to be true. I guess you'd need to be a multi millionaire with a massive dome observatory on your estate lol

[John]

6 minutes ago, Paz said:

Oops - I wish I did but the reality is it is a typo! 

You have got a 14" apo though

[Chris]

1 minute ago, John said:

You have got a 14" apo though

I wonder if one of those even exists on this planet ? ? ? If so I'll start emptying my two's and one's jar  

[John]

5 minutes ago, Chris Lock said:

I wonder if one of those even exists on this planet ? ? ? If so I'll start emptying my two's and one's jar  

APM / LZOS list a 510mm F/12.7 apo ...... I you have to ask the price ......

[Chris]

27 minutes ago, John said:

APM / LZOS list a 510mm F/12.7 apo ...... I you have to ask the price ......

20" ! 6500mm FL ! 

[Paz]

On 01/01/2017 at 23:09, John said:

APM / LZOS list a 510mm F/12.7 apo ...... I you have to ask the price ......

There should be laws preventing the posting of such temptations on this forum! 

[Chris M48]

I've decided to go for the ST150 together with a 2" Baader semi-APO filter that I picked up for £75. The Crayford Focuser upgrade will have to wait a while. I used to have an ST100 so I've got an idea of what's ahead although I never had filters in those days. My ED100 is an old friend that will stay with me for the duration.

Thanks all for the help and interest.

Happy New Year.

 

[John]

Happy New Year to you too Chris and I hope you enjoy the new scope

[mikeDnight]

11 hours ago, Chris M48 said:

I've decided to go for the ST150 together with a 2" Baader semi-APO filter that I picked up for £75. The Crayford Focuser upgrade will have to wait a while. I used to have an ST100 so I've got an idea of what's ahead although I never had filters in those days. My ED100 is an old friend that will stay with me for the duration.

Thanks all for the help and interest.

Happy New Year.

 

Three of my friends have owned the ST150 and I've used them many times. They are truly excellent RFT's and are a joy to use. When used for the purpose for which they are made they are stunningly good performers. Rich field views of things like the double cluster and the Pleiades are glorious, and sweeping through the milky way will have you transfixed. They will give reasonable views of the moon and planets but be aware the CA will be evident. Probably a top power of around 200X would be its limit. It's a specialist instrument and excels in its intended field. 

Personally I'd accept it for what it is and not bother with a CA filter for night time viewing. The scope has sufficient light grasp to pull in countless fuzzies, including galaxies, and delivers a sharp contrasty and well defined view of them. You'll love it!

Just something to be aware of is that some have been known to have poor spherical correction. One that my friend bought was terrible, but he sent it back and received a really excellent scope in return.

It will complement your ED very well!

Mike ☺