Frac shootout report

[bomberbaz]

I have recently acquired a scopetech STL 80 F12.5 and I wanted to compare it with my SW 100ED frac.

Set both up on the Sky Tee mount as well as the TS finderscope. Gave me opportunity to check all were collimated as one, inc the RDF. ( There is about a 1/2 degree of mis-collimation between the two OTA's in the AZ movement)

This setup works a dream and finding objects is getting much easier for me.

I digress, weather didn't play ball, I can hear the rain outside as I type this. Good job I got the rig in as soon as i did.

As mentioned, weather didn't play ball so didn't manage too many objects, I got Jupiter, the Moon, Vega and Albireo.  I was just getting onto the dumbell when the cloud came over.

Both OTA's had 25mm Vixen NPL in them scopetech x 40 and SW ED x 36.  I had planned to slap OVL zooms in them later with the aim of trying to match exit pupil rather than magnification.

Jupiter didn't really give me that much to think about, too low down really and a bit mushy in both OTA's.

The Moon however was a different story. First the ED, lovely clear, crisp, well contrasted view, sharp detail along the terminator, the NPL eyepieces really are a gem. Switch OTA now. At first I thought the scopetech was giving some colour fringing until I centred it properly in the EP (Collimation issue as mentioned) and bang, the view was equally as good as the ED or possibly slightly better. It was a little dimmer due to the reduced aperture which just made it ever so slightly better, a little sharper. 

If you didn't have them both side by side, you wouldn't notice it. The actual difference was negligible and certainly nothing to be concerned about.

On Vega and Albireo both provided identical views, I couldn't tell any difference.

I would like to have another shoot out and this time get onto some clusters, small bright nebula and more difficult doubles. Also I want to push the magnification up on both to see how far I can take them. 

The scopetech was bought on a whim as my buddy has a penchant for long F ratio fracs so wanted to see why, I can see the reason now. Lovely and light, very sleek and incredible views for something that is relatively low costing. 

Quick picture of the rig, I can (just) manage to carry it outdoors fully setup.

 

[Franklin]

I've always thought that long achros are capable of giving shorter EDs a run for their money, nice scopes👍.

Lovely looking setup Steve, but that little Pronto extension pillar looks like it's about to pass out 😀.

[johninderby]

The Scoptech 80 is a cracking scope and can literally be an eye opener for those that  assume that ED or APO scopes are always better. Probably has a lot to do with most being used to the modern low cost achros. Yes the ScopeTech 80 ia a planetary specialists but when you are looking at planets……🙂

 

Edited December 10, 2021 by johninderby

[Stu]

Lovely scope Baz. I’ve got both the f15 and f12.5 on loan from FLO still and they are both excellent. Some slight differences in diffraction rings on stars but basically what’s visible in one is visible in the other from what I’ve seen.

[johninderby]

Arrgh. 🤬🤬🤬

After this thread thought I’d get the ScopeTech 80 f/15 out but the sky that was completely clear 10 minutes ago is now wall to wall cloud. 

Edited December 10, 2021 by johninderby

[John]

Interesting report Baz

"....the view was equally as good as the ED or possibly slightly better...."

That caught my eye. Can you be more specific ?

Resolution, contrast or something else ?

 

[johninderby]

A temporary break in the clouds so was able to use the ScopeTech 80 f/15. Beautiful razor sharp lunar views. 👍🏻👍🏻👍🏻

 

Edited December 10, 2021 by johninderby

[bomberbaz]

3 hours ago, John said:

Interesting report Baz

"....the view was equally as good as the ED or possibly slightly better...."

That caught my eye. Can you be more specific ?

Resolution, contrast or something else ?

Not really sure John, "possibly slightly better" being the key but just felt it was slightly more contrasty and this was possibly down to lower light pull of the 80 over 100 helping lift the detail out. 

I shifted from one EP  to the other several times and just preferred the 80mm over the 100ED. (both were superb)

As I said further down the thread, I will explore this further when the skies permit. 

[Epick Crom]

Nice setup @bomberbaz👍

[bomberbaz]

19 hours ago, johninderby said:

A temporary break in the clouds so was able to use the ScopeTech 80 f/15. Beautiful razor sharp lunar views. 👍🏻👍🏻👍🏻

 

 

Yeah I have never used a frac longer than F10 before and it is something of a revelation to me. I doubt I could get away with an F15 though, Mrs Bomberbaz is getting a little shrewd these days around my astro gear and has been asking questions 😂

[Stu]

32 minutes ago, bomberbaz said:

Mrs Bomberbaz is getting a little shrewd these days around my astro gear and has been asking questions 😂

Be afraid. Be very afraid! 😱🤣

[neil phillips]

Kind of backs up what i have been saying about the little 70mm Capricorn F12.8 And likely the reasons its performing so well is the long focal length. Even though its mass produced and even though its achromatic. Those on a budget ignore at your peril. Sounds like i would like that 80mm scopetech F15. Keep looking at the Bresser F13.2 That sounds like a good shoot out 

[johninderby]

The f/13 Bresser should be a very good scope for the money.I like the Bresser fracs. 👍🏻

The ScopeTech has better optics and build quality though. Takahashi sells a version of the Scopetech  under the Starbase name. ScopeTech and Starbase are made by the same company. The ScopeTech is built for collectors of classic fracs in Japan where they want an old style scope.Not really meant for export.

Edited December 11, 2021 by johninderby

[neil phillips]

19 minutes ago, johninderby said:

The f/13 Bresser should be a very good scope for the money.I like the Bresser fracs. 👍🏻

The ScopeTech has better optics and build quality though. Takahashi sells a version of the Scopetech  under the Starbase name. ScopeTech and Starbase are made by the same company. The ScopeTech is built for collectors of classic fracs in Japan where they want an old style scope.Not really meant for export.

No of course i realize a Japanese lens is likely better than a mass produced chinese one. But if its not too under or overcorrected. It will likely perform well. And dont forget 102. F13.2 may possibly beat 80mm. F15 as resolution and light is greater.

But of course all this depends on the actual figure of the lens which may be more hit and miss. With the Bresser. The cell in the bresser from what ive read is plastic. But that doesnt always matter, as long as its held collimation. Which again apparently these bressers with plastic cells do not always hold.  Would love to see a shootout of the bresser against the scopetech. I still think get a good one. thats held collimation. it could potentially give the scopetech a real hard time. 

 

[johninderby]

Could allways get out Big Red. 🙂

[neil phillips]

3 minutes ago, johninderby said:

Could allways get out Big Red. 🙂

Looks real nice John. 

[Sunshine]

Nice comparison of two great scopes, I can imagine it would be loads of fun comparing two refractors side by side.

[bomberbaz]

5 hours ago, johninderby said:

Could allways get out Big Red. 🙂

something about coloured OTA's just makes me drool. Seen one like this from @moriniboy, beautiful looking scope. 

Also seen a lovely blue one but can't remember where but just that it looked amazing.

Aesthetics, offering nothing but beauty but just hmmm. 

[IB20]

The long focal ratio Starbase/Scopetech 3”s make super solar system scopes. I love the peep hole system, I find I use it more than the finder. 

I’ve been very impressed with mine for WL solar, doubles, lunar and planetary viewing. 

Interesting to hear how the Scopetech continues to do against the 100ED. I’m currently waiting for a 76DCU to arrive which I intend to pit against the Starbase in some fun shootouts.