Refractor V Reflector test.

[The Flinty Fox]

Hi.

I haven't posted for a while so I thought I would. For a while now I've owned both a Skywatcher 150P and a William Optics 80mm ED refractor and have wanted to do a side by side comparison of the two, so the other night finally managed to do it. I had them mounted on an azimuth mount so I was quickly able to  switch from one to the other, the eyepieces used enabled the same mag to be achieved, 41X. The reason was not to see which one performed the best but to see how things just generally looked between the two as people are saying how much nicer stars look through a refractor than a reflector. You could call FOMO if you wish. 80mm V 150mm perhaps not a fair comparison but these are all I have.

 

This was my first go at this sort of thing so I will be doing this more and on more objects, particularly the moon, to try and get a good idea of how they compare. 

I should Have waited for the scopes to cool properly but it was already getting late but towards the end things did steady, I think I must of been out at least an hour+.

Objects looked at were Polaris, M35, Orion Nebula and Sigma Orionis. 

Sigma Orionis was the first and last object I looked at so first attempts were not great as scopes had not cooled properly, but by the end things had improved and were looking good through both scopes with some nice colour, of what I could detect anyway, but couldn't decide which view I prefered. The WO 80mm was more steady than the 150P but when the 150P did steady itself the views I thought were still nice.

The view of the Orion Nebula, to me, were better through the 150P. It was brighter more structure and just gererally easier to view. 

Polaris again I thought was just nicer through the 150P, it was brighter with the secondary easier to see and the defraction spice do look nice. The WO 80mm was nice but less impressive.

M35 was a bit of a difficult one. The 150P was brighter and easier to see but the WO 80mm was perhaps a bit steadier but dimmer, but overall I think the 150P maybe just did it.

This isn't an exact scientific experiment, I'm just seeing how things look but it is a bit early to come to any firm conclusions so more looking is needed. Next time I will allow proper cooling of the scopes.

The moon will hopefully be up this weekend so will try that and see how that looks.

Hope this all makes sense.

Stay safe.

 

 

[John]

Makes sense to me - its fun to compare the views with different scope types

[ollypenrice]

Just at a time when we need national unity you post this!!! 

🤣lly

[tomato]

I risked starting a “which processing software is better” thread over in the imaging section, but issued a firm disclaimer.☺️

[mikeDnight]

You've got a task on your hands with this one!  The two scopes are so different in their abilities that I'd find it a real struggle to pit one against the other with any meaningful conclusion. The 80mm will make a great grab and go. It will show the belts on Jupiter very clearly, along with shadow transits and the great red spot. Saturn's rings and Cassini's division and albedo markings on Mars are also within its reach. With a binoviewer and 2X barlow the 80mm makes a wonderful lunar scope too!

The 150mm Newtonian is in a whole different league.  This will show detail within Jupiter's great red spot. Saturn's rings will be divided into the A, B & Crepe ring, with the Cassini division completing a circuit. The Enke minima will easily be seen in the A ring, and possibly on a good night the Enke gap. Saturn's globe will show an equatorial belt and possibly a temperate belt, and there will be noticeable polar darkening, and much more. Jupiter will be more akin to a Voyager image with festoons, garlands and white ovals, and Mars will take on a complex mixture of dark albedo patches and fine channels (not canal's!), with ice and clouds, and a globe that revolves as you watch. Deep sky will be a joy in the 150 and virtually nothing that's worth looking at will be out of its range.

Now if you were to do a 4" refractor vs a 6" reflector thread, you'd undermine the work of the United Nations in seconds. 

[Mr niall]

It is really interesting to compare different scopes, but like others I'm not sure how much of a "one vs the other" type conclusion you would glean from something like this. The 150p should blow the 80mm out of the water in every single category (not withstanding the obvious things like star shapes). Its just sooo much bigger!

I did a similar thing with a 70/900 frac and a 130p flextube recently (not by design just had two people with me) and the 130 was considerably better in every single capacity that was measurable.

What I will say though is that it is super interesting to see how well a scope performs - and this is only the sort of thing you can do I think when you have another scope there to compare it to so from that perspective I bet it was a really interesting thing to do! Thanks for sharing; I'll bet this would also be of interest to those looking to buy a scope.

edit; sorry I just mean for visual of course. For photography it would be a very different sort of comparison!

Edited March 25, 2020 by Mr niall

[John]

For interest, you could try making a card aperture mask for the 150 newtonian. Something like this:

If the aperture falls between the secondary vanes you get an unobstructed scope albeit of smaller aperture. You get some nice results on double stars and bright targets such as Venus - "refractor-like" views

[The Flinty Fox]

Hi all and thanks for the reply's. 

I agree that comparing a 150mm scope to an 80mm scope is a bit unfair towards the 80mm, and it is proving to be not as straightforward as I initially thought. A 100mm or 120mm refractor would be a more meaning comparison but unfortunately I don't have one so all I can do is work with what I have.

I guess what I'm interesting in is how the two different designs compare rather than actual performance, thou I will probably be attempting a performance comparison on the Moon this weekend if the weather is good, but I will be making a note on star shapes.

I have tried the aperture mask before but the one I made wasn't very good so I might try again.

Anyway I had another go last night. The objects looked at was Mizar, Asellus Tertius and Primus and Cor Caroli.

The scopes were allowed to cool for a least 1 hour before starting and the same eyepieces were used to achieve same mag of 41x, a Baadar 18mm BCO in the 150p and a Tele vue 13mm volcano top in The WO 80mm.

Looking at Mizar I found the view through the 150p to be overall fresher than the 80mm but I think this could be an eyepiece/mag issue as the 80mm is having to work slightly harder achieve same mag, the background in the 80mm being slightly darker. That said I found Mizar and its companion to be slightly whiter and more gleamy in the 150p but in the 80mm star images were more behaved though slightly less white and less gleamy. Overall the liked the views through the 150p better.

Asellus Tertius and Primus was interesting. I was able to frame both double stars in the field of view but as the 150p is a fast-ish Newtonian I was  only able to view the doubles one at a time, viewing both meant they were at the edges and so unreasonable.  The 80mm didn't suffer that problem and so both were seen and split. I did view the doubles individually through both scopes and I enjoyed the views through both, though, the star images in the 80mm were better behaved and I suppose a tad more star like but I think the 150p can produce nice star images when things settle but are generally less well behaved. overall the views through the 80mm, for the reason both could be seen at the same time, were nicer.

Cor Caroli was a little rushed I confess and I also began trying different eyepieces/mags in both scopes so the overall conclusion on this one isn't that clear. I liked the views through both but in different ways. Clearly more experiment is needed.

I think so far from what I have seen if you are the type of person who likes double stars then a good refractor is probably the thing you should get. This is not groundbreaking news I know but this is something I have only ever read about, and so to actually see this for myself and come to that conclusion is I suppose revealing, if that makes sense. 

Having said that I like the 150p and I think it is pulling its weight and performing well, it will be interesting to see how they both compare on the Moon and I will be trying to check actual performance.

Hope this all makes sense.

Thanks.

Paul.

 

 

 

 

[The Flinty Fox]

Hi.

Should of done this sooner i'm a bit slack when it comes to posting, anyway, had a look at the Moon and must say this comparison thing is not as easy as it looks.

The comparison was done over three nights, I am comparing a William optics 80mm to a Skywatcher 150p, for fun mainly.

The first night didn't really reveal anything the Moon was a bit low and seeing wasn't great and got steadily worse as the session progressed, but there were tantalising glimpses that the 150p wanted to show more but the poor seeing did not allow it. The magnifications used were 136x in the WO 80mm via a 4mm Vixen LV4 and 130x in the 150p via a Tele vue 13mm smooth side barlowed in the Baadar Q-turret, and a good barlow it is.

I did decide to take a look at Venus as it was near by and found that I preferred the view through the 150p than the Wo 80mm. The 150p showed Venus a half lit white snooker ball and couldn't see any false colour which is what I saw through the WO 80mm. The 150p did show diffraction spikes but I think I find them less distracting than false colour. 

The second night was a bit more fruitful. I concentrated on the crater Copernicus and the surrounding area and after much toing and froing from each telescope I felt satisfied that indeed I was able to see details through the 150p that I couldn't see through the WO 80mm. There were details within a small area North of Copernicus that were visible through the 150p but not the WO 80mm. Seeing was still a bit of a challenge but when it was good the differences were quite clear to see. The Moon also appeared much brighter through the 150p and had a more neutral colour.

It wasn't long after I had done this that a though occurred to me, or maybe anxiety, that perhaps the reason I was able to see more through the 150p was because the Vixen LV4 that I used wasn't performing to scratch. So I decided to go out for a third night to compare the Vixen to the other eyepiece I have, which to be honest isn't that many. I decided to use just the one scope, the 150p, for this comparison. The eyepiece used where the Vixen LV4 188x, Tele vue 13mm barlowed in the Baadar Q-turret 130x and a Tele vue 10.5mm also barlowed in Q-turret 161x. Again after much toing and foing I finally concluded that the level of detail seen through each eyepiece was petty much the same though there were times when I felt I could be a tad more through the Vixen LV4, which was good. Main difference where brightness and contrast as the mag went up.

So in conclusion, and I'm not an expert, as far as I can tell everything seems to be working well and that my toleration, is this a word?, of false colour is perhaps not as high as I though. As for the two scopes, I think I might be preferring the views through the 150p but agree they are very different and have different uses. 

Anyway hope this makes sense this is probably stuff I've missed out.

Thanks Paul.

 

[Alan White]

Interesting thread here Paul, somehow missed until just now.
Thank you for sharing your thoughts and findings.

Clearly this is very much a personal thing for us all, depends upon seeing, local conditions,
our eyesight and many other things too.

I own both Reflectors and Refractors and flip flop between my scope of favour,
often depending on the time of year and what I am observing.

An 80mm or 150mm is a Mike above says, not quite a direct comparison as the amount of light collected and resolution is not equal.
I have done similar comparisons with my then ED80 Skywatcher and 150p Skywatcher and kept the 150p for a while.
Had aperture fever and bought an OOUK 250mm f5 on Dobson Mount.

I now own a 150mm f5 OOUK  Newtonian, the 250mm f5 OOUK and a very fine Vixen ED103s Refractor.
After a lot of thought I put the 250mm up for sale, but I recently withdrew it as selling such a scope at present times is not essential supplies or trips.
The other two had a fight to do and still are having that fight, but in all honesty I prefer no diffraction spikes, that annoy the heck out of me some nights.
If one of the two had to go, it would be the 150mm, but it does not need to and will stay for nights when I desire more aperture, 
but that could be taken up by a 150mm Refractor perhaps, but not at present as funds directed elsewhere for a couple of years more yet.


 

[The Flinty Fox]

Thanks Alan. 

I have occasionally looked at the orion optics scopes, mirrors and they do look nice but I think I'm happy with the performance of my 150p for now. Maybe if the mirrors fail might upgrade. 

150mm v 80mm is unfair but I think my interest is in how different objects simply look through them. Aesthetics. I do like both and to me have different uses. 

 

One thing I do like about the 150p is eyepiece holder location, it always seems to maintain same height of the ground and I don't need to extend mount legs which makes it more stable. 

Interesting that the vixen and the 150OO are still having to fight, is it that close?

Thanks Paul. 

[Alan White]

2 hours ago, The Flinty Fox said:

One thing I do like about the 150p is eyepiece holder location, it always seems to maintain same height of the ground and I don't need to extend mount legs which makes it more stable. 

Interesting that the vixen and the 150OO are still having to fight, is it that close?

I too like the eyepiece location for the Newtonians, as to mirrors, my old SW150p had a great set,
The OOUK wins on size and weight, its an aluminium tube and slimmer.

As to the fight, well it's more about my heart than what I see, 
The Vixen I have is superb optically and punches above its size and weight, I prefer the image it presents to my eyes.
But I have a fond spot for a 150mm Newtonian, so that's why it's still kicking and screaming and not going.

The reality is that one day I may go for a second refractor in 130-150mm size, but my pockets cannot do that presently or in the near future.