Whie Light Solar Set-up (BRESSER AR-102xs/460 - TS Hershel Wedge)

[johninderby]

New Whie Light Solar Set-up (BRESSER AR-102xs/460 - TS Hershel Wedge)

While I did like the Orion 120 frac with a Lacerta 2" Herscel wedge it wasn't the lightest and needed the Skytee II mount. I decided to go with a new light weight setup that would fit on a photo tripod and could be carried outside one handed but would still have decent aperture.

After looking around decided on the Bresser Messier AR-102xs/460 Hexafoc OTA as it was light and compact but had decent optics. Build quality is excellent although the included accessories are rubbish and should be put in the bin except for the eyepiece which is actually quite decent and perfectly usable.While it uses ED glass they don't state what it is so I take that as being the minimum standard that can still be called ED. Did some testing on the moon and Jupiter last night and CA simply wasn't a problem.Yes there was some but very minor and more like what you would expect of a f/10 achromatic refractor which is good cnsidering this is an f4.5. So the ED glass (whatever it is) does work. Impressd with the focuser. It really is very good. Ordered the 1:10 upgrade for it. Removed the supplied finder shoe and fitted a Skywatcher one. Also peeled off that tacky aluminium name plate thing of the side. Looks much nicer without it.

In keeping with the lightweight theme decided to give the TS Herschel 1.25" wedge a try. Very compact and leightweight and comes with all the filters incuding one that has the same specs as the Baader Continuum filter. Very well priced as well. Solid little bit of kit it is as well and has a brass compression ring on the eyepiece holder.

Bresser Refractor Messier AR-102xs/460 Telescope with Hexafoc Focuser 

Richfield telescope with ED glass lens. 6x30 optical finder with crosshair 
Focuser with 65mm open diameter. 50,8mm to 31,7mm adapter with integrated T2-thread 
Diameter= 102mm; Focal length= 460mm; F/4.5
Vixen type 44mm Dovetail plate with stainless steel rail 
Dimensions: 46x14x14cm / Weight: 2,8 KG / Tube diameter: 104mm 

TS-Optics 1,25" Solar Prism with Polarizing and Narrowband Filter

♦ High-quality surfaces for very high contrast
♦ Enclosed housing with integrated light trap - no escaping stray light
♦ Cooling fins for quick removal of the heat
♦ 1.25" polarising dilter for screwing into the eyepiece or into the filter for continous adjustment of the brightness without without additional colouring.
♦ 1.25" narrow band interference filter for significantly enhancing the contrast of the solar surface. Especially faculae regions are shown better. The filter has a bandwidth of approximately 40 nm and a peak at 540 nm. Now sun observation is possible with fast Fraunhofer refractors, as the chromatic aberration is removed.

Observing report to follow as and when the sun puts in an appearance.  ?
      John
 

Edited May 27, 2018 by johninderby

[johninderby]

Bought the Manfrotto geared tripod and 405 geared head years ago. Just out of interest looked up the current prices and was shocked to find the total would now be about £860.00. And I thought astro gear had shot up in price!!!! The 405 head has been modified to remove the centre section thus making it an alt/az head.

Note the size of the wedge compared to a Skywatcher Dielectric 1.25" diagonal.

 

Edited May 27, 2018 by johninderby

[Stu]

Looks an excellent and very portable solution John. Will interesting to see how such a fast scope performs, very well hopefully  

[Mark at Beaufort]

John that looks an incredible scope for the money. I really look forward to your review which I know from the past will go into good detail.

How easy was it to change the finder bracket?

[johninderby]

Just had to drill a couple of holes in the tube. Focuser comes off easily and stuffed a small towel inside the tube to stop any bits getting on the objective and put some wide masking tape below where the holes would be drilled to catch any bits as the fell. Then afterwards pat down the inside of the tube with masking tape to collect any residual bits. 

The stock bracket screws on just behind where the new bracket fits.

Did some lamp post observing this aft to check CA but virtually nil as you can see in this pic. Rubbish pic as it was taken holding a camera to the eyepiece but gives the idea.

Think it will made a great wide field scope. 

        John

 

 

[johninderby]

Well first light.....sort of. Sun peeped through the clouds for about a miniute. Just enough time to align the solar finder and take a quick look at the sun. Have about 20mm infocus travel to spare and sun was the same green as a Baader continuum filter. Then of course the clouds spoiled  everything. 

Oh well at least the first glimpse seem’s promising. ?

        John

Edited May 27, 2018 by johninderby

[johninderby]

Tried the Explore Scientific 3x focal extender today and find it suits this scope & wedge perfectly. Using the 7.2 - 21.5 zoom eyepiece at lowest mag the full disk of the sun just fited in the FOV and the image was still clear at max mag. Pefect match. ?

The extender wouldn't fit all the way into the eyepiece holder and bottomed out so took a Baader T2 15mm extension piece and ground three slots to fit over the three screws in the top of the eyepiece holder so it would screw  on properly. Nice neat solution that looks factory.

The TS wedge comes with their own version of a continuum filter and quite frankly can't tell any difference between it and the Baader. Performs exactly the same.

Impressed with this scope every time I use it. The optics are definitely better than a plain achro with very little if any distortion and almost no CA if you're usng a decent diagonal. Perhaps it should be called a Semi ED? Hmmm reminds me of the old Semi APO discussuions (arguments?) of a few years ago.  ? 

 

Edited June 23, 2018 by johninderby

[LukeSkywatcher]

Beautiful looking scope. I might just get me one of those.

LOL.

You are right about CA in this scope being almost non-existent.

Whats the name plate you mentioned?. Is it the silver bar on the dovetail?. I removed it so the scope would mount on AZ5.

[johninderby]

It’s the aluminium plate with the name of the scope stuck on one side. Just irritated me for some reason so off it came.  ?

 

Edited June 23, 2018 by johninderby

[Mark at Beaufort]

I really pleased that this scope is performing well. I was worried when I read a negative report recently. Paul glad that the scope is able to be fitted onto your AZ5. I look forward to more observing report when we get astro darkness back.

[Sunshine]

That is an attractive little scope!

[johninderby]

One problem with a new scope like this is that so few have actually got their hands on one that most opinions are based on supposition not fact. Yes it’s no APO but it is still a nice well,built scope with decent optics and very well priced.

Lot of negative opinion on CN from those that haven’t actually looked through one. Lot of good people on CN but plenty of self appointed “experts” as well that are anything but.  ?

Remember a while ago reading widespread opinion on CN that the Carton 100 f/13 optics were  just cheap low quality optics no better than the cheapest Chinese stuff. Then someone on CN actually took a look through a Skylight scope and found out how wrong they were. 

 

Edited June 23, 2018 by johninderby

[Mark at Beaufort]

36 minutes ago, johninderby said:

One problem with a new scope like this is that so few have actually got their hands on one that most opinions are based on supposition not fact. Yes it’s no APO but it is still a nice well,built scope with decent optics and very well priced.

Lot of negative opinion on CN from those that haven’t actually looked through one. Lot of good people on CN but plenty of self appointed “experts” as well that are anything but.  ?

Remember a while ago reading widespread opinion on CN that the Carton 100 f/13 optics were  just cheap low quality optics no better than the cheapest Chinese stuff. Then someone on CN actually took a look through a Skylight scope and found out how wrong they were. 

 

Nicely put John. I am sure it will become a popular scope especially for white light and Richfield observing.

[Stu]

My concerns were/are based around the challenges of producing fast optics in a relatively low cost scope. By definition. SA and field curvature will be more pronounced than in a slower scope and that is likely to kill the fine detail that I find so appealing with white light solar at high powers. The report linked to previously showed plenty of issues in this respect but I'm sure as a widefield, highly portable scope it will be excellent. For full disk white solar viewing, again I'm sure it is very good but unlikely to be able to compete with an f10 with well figured optics for instance.

They say though that the best scope is the one you use most, and these look very useable and convenient.

[LukeSkywatcher]

3 hours ago, johninderby said:

It’s the aluminium plate with the name of the scope stuck on one side. Just irritated me for some reason so off it came.  ?

 

Mine didnt have one.

[LukeSkywatcher]

"Yes it’s no APO but it is still a nice well,built scope with decent optics and very well priced."

Agreed.

[johninderby]

11 minutes ago, LukeSkywatcher said:

Mine didnt have one.

Lucky you.  ?

[johninderby]

What I’m finding is it can be used for lunar and planetary and gives pleasing views and the CA is so minor that it doesn’t bother me.  So while it is naturally a wide field scope it is good enough for general observing.which is what will make it a great travel,scope as it can be used for any type of observing even if it’s not the ideal scope for everything. 

[DHEB]

I have had this scope for a year now and can confirm that it is very good for general wide field low power observing. It is a nice all-round telescope and specially well suited for traveling. Chromatic aberration is present and obvious when looking at bright object. With 460 mm FL it is not easy to reach high magnifications required for planets and Moon, but it is not impossible either. I use it for variable star observing and bright DSO's and I am very happy with it. It is excellent quality for the price.

As for the CA you can see these photos, taken by attaching a DSLR to the scope with the extension tubes supplied:

Detail of a birch tree (CA almost not existent):

 

Detail of a roof border (CA noticeable)

Edited June 23, 2018 by DHEB
Added photos

[tico]

johninderby,

How well has the Hershel prism given you?
Have you been able to get a sharp image with medium magnification? Can you observe solar granulation?
I ask it because I have a refractor like this and I am thinking of doing solar observation with it.
Thanks and best regards,
Tico.

[johninderby]

9 minutes ago, tico said:

johninderby,

How well has the Hershel prism given you?
Have you been able to get a sharp image with medium magnification? Can you observe solar granulation?
I ask it because I have a refractor like this and I am thinking of doing solar observation with it.
Thanks and best regards,
Tico.

Hi

Have moved on to a different white light setup now. The 102 did work well with the solar prism but didn’t show a lot of granulation which is why I’ve chaged to a bigger scope.

 

[tico]

Thanks for your reply.
And what such result has it given compared to the previous refractor? better resolution and images of solar granulation?
Best regards.

 

[johninderby]

Not used it much yet with no sunspots to see. 🙁

But does show more granulation and beter resolution.The longer focal length helps as well.

Edited October 11, 2020 by johninderby

[Stu]

1 hour ago, johninderby said:

Hi

Have moved on to a different white light setup now. The 102 did work well with the solar prism but didn’t show a lot of granulation which is why I’ve chaged to a bigger scope.

 

I don’t think it’s the size John, it’s the quality of the scope and, more specifically the amount of Spherical Abberation I think, which kills the fine detail. Such a fast achro was unlikely to produce the best results; my Tak show’s granulation in bucketfuls with similar aperture.