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First Light on used ST80


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54 minutes ago, SuburbanMak said:

@Laurieast These are fantastic pictures - almost makes me want to buy the EQ conversion kit for the AZGTi - did you take at prime focus with a DSLR & if so what kind of exposures were involved? 

Thanks!

These are prime focus with a Canon EOS 500D, on the AVX Mount, unguided (not ventured into doing that yet)

M42 44x 60sec at iso 400 , 20x flats and 20x bias frames stacked in DeepSkyStacker. Levels and curves etc stretched and pulled in Photoshop.

M31 32x 70sec at iso 400 , 20x flats , may not have done bias (running that now in DSS) . + Photoshop.

I have tried going up to iso 800, but it looks as though it's bringing in too much sky glow.

Not bad for a sub £100 scope, had it for about ten years now 😃 . I don't think those aluminium focus knobs are available now, which is a shame as I need another one.

Despite now having an Evostar 80ED, the ST80 is staying!

 

Edited by Laurieast
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Over the past couple of days,  with no chance of any observing , I've acquired a small tin of blackboard paint and a suitable brush, had the st80 apart , and made the inside nice and matt black .While it was in pieces, I had a look at the focus mech. , not the treacly grease reported as often there,  perhaps a previous owner sorted that, but while I had it apart it made sense to give it a good clean and a new dab or three of lithium grease before it went back together.

The chap in the video didn't mention the focus lock and adjustment strip , which n my model is a black plastic strip , sitting in a channel under the focus lock screw. Not sure if it is supposed to be retained in that channel , but mine fell out when I removed the tube . I'd imagined the lock and adjustment grub screws just pressed on the tube itself, but apparently they push this black plastic strip down on to it, a much better option, less likely to mark the tube. That got cleaned and a smear of grease on the tube-facing side before going back in place too.

The blackboard paint is supposed to dry in 2 hours, but I left the 'scope in bits overnight just to be on the safe side . Will all this make a noticeable difference ? No idea, but it did keep me safe from a few hours of online browsing for things to buy, so the £6 for paint and a brush were probably a wise investment :evil4: 

Now it is all back together, looking nice , working smoothly , and waiting for a gap in the clouds .... please .....

Heather

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It's looking like first-light for my ST80 tonight. Haven't done any fettling to it yet - I thought I'd get some use first, then I'll be able to see any improvement.

I'll probably get some flocking material, as I want to do the baffle tube on my Skymax90 before I sell it.

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On 11/03/2021 at 15:48, SuburbanMak said:

......   By this time I was feeling brave so I blacked the edges of the lenses with a few coats from a Sharpie,  I marked an arrow across the two lens edges so that I could put it back again in the right orientation (& made sure I didn't colour over that little bit). ......

 

As the chap on the video says, it is obvious which way round the thicker lens goes , but the front element , not so easy to distinguish once you've been turning it over to clean with the baader magical stuff ... what happens if you foolishly put it in the wrong way round ?

Ahem, :blush: not telling how I know this, but what you see is a circular halo around any bright point of light (like a streetlamp which is all you can see due to 100% cloud cover) , a solid circle of light like the ones around saint's heads in medieval paintings .

Should have borrowed your sharpie arrow strategy ! Fortunately easily sorted, no harm done. 😌

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24 minutes ago, Tiny Clanger said:

Ahem, :blush: not telling how I know this, but what you see is a circular halo around any bright point of light (like a streetlamp which is all you can see due to 100% cloud cover) , a solid circle of light like the ones around saint's heads in medieval paintings .

It's like when you take eyepieces apart, and then ....😱

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  • 2 months later...

Posting the latest iteration of my ST80 system - I’ve gone for a TS Optics 2inch focuser and a Baader 31mm Hyperion Aspheric.  
All goes together beautifully solidly and in daylight at least delivering the desired sharp, bright, widescreen TV effect. 

Now need some clear skies to star-test

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Edited by SuburbanMak
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24 minutes ago, SuburbanMak said:

Posting the latest iteration of my ST80 system - I’ve gone for a TS Optics 2inch focuser and a Baader 31mm Hyperion Aspheric.  
All goes together beautifully solidly and in daylight at least delivering the desired sharp, bright, widescreen TV effect. 

Now need some clear skies to starters…

D1D5627A-8A49-4957-A653-B008A5BFACA2.jpeg

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Great job there, its looking a special piece of kit now, hope your first light dark night, goes well and gives you improved views, 👍

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39 minutes ago, AstroNebulee said:

Great job there, its looking a special piece of kit now, hope your first light dark night, goes well and gives you improved views, 👍

Thank you - I did look at whether it was worthwhile hanging in for an ED scope but most seem to be f7.5 so you’d end up with a similar TFOV to the ST80 with a 1.25 . 
Will put a note on here as to how it turns out. 

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That is an interesting upgrade for the ST80. I hope the focuser can reach focus on astro targets - sometimes the 3rd party add-on focusers struggle with the ST80's with regards to inwards focuser movement.

I'd also be interesting to know what % of the field of view is sharp with the 31mm Aspheric eyepiece in the F/5 refractor.

Looking forward to your feedback from under a night sky :smiley:

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10 minutes ago, John said:

That is an interesting upgrade for the ST80. I hope the focuser can reach focus on astro targets - sometimes the 3rd party add-on focusers struggle with the ST80's with regards to inwards focuser movement.

I'd also be interesting to know what % of the field of view is sharp with the 31mm Aspheric eyepiece in the F/5 refractor.

Looking forward to your feedback from under a night sky :smiley:

Always mildly alarming when an expert uses the word “interesting” :) 

 I am getting to focus on my reference church spire about a quarter of a mile away with over an inch of in-focus to spare so am optimistic this will be workable. 
 

I’m prepared for a degree of aberration in the outer field, the view is so massive that for my eyes the field stop is already in my peripheral vision, however as you rightly say, the acid test will come under a clear sky! 
 

Hopefully I can test this out later, there is currently a break in the murk over Hampshire… 

 

 

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On 22/02/2021 at 15:12, Tiny Clanger said:

 

 

Good find! I can see myself doing most of this to my ST102 when the rain comes round again. Just need to find something similar for the Bresser 102L also...

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Update on “project widefield”. 
 

Well it certainly works :) Had this out Friday night sweeping through Cygnus & South Easterly clusters. 
 

Most importantly I was able to achieve focus with all the eyepieces with in the end plenty of infocus to spare. ( @John - thank goodness! ) 
 
The view with the 36mm Baader Hyperion Aspheric is HUGE!  Something like 5.6 degrees & with 12.9 x mag. On the downside there is edge abberation in something like 15-20% of that field and it’s quite marked at the very outer edge. However the majority of the field is sharp and the overall effect amazing on wide clusters and the Milky Way. The Hole in the Cluster area, Cygnus central area, M39, Summer Beehive all quite stunning & this was the desired effect. Even with some fuzzy edges the star field is engaging and criss-crossing satellites become an attraction in themselves. 
There are just so many stars…
 

The view is quite bright and very suspectible to local light pollution - neighbours security lights had a big impact especially when looking low down toward Ophiuchus and Sagittarius later in the evening. I also need to find a way to attach the RDF as the shoe went with the old focuser  - weirdly the view is so wide & rich that it’s a bit bewildering so an RDF would be very handy. Can’t wait to get this out somewhere really dark though.
 

Otherwise the focuser itself is a marked upgrade on the SW factory fit. To my relief it’s gone on nicely and collimation may even be a little better than it was before - in two minds whether to tinker further with this as it’s not material to enjoyment and Might go the other way! 

Everything is locked securely in compression rings and and the 2-speed monorail gives smoothness and sensitivity that really add speed, accuracy and reduce vibration when focussing.  I tried the Baader Classic Orthos & 2.25x Barlow in the 1.25. converter and was able to rack up magnification to 150x and achieve precise focus to successfully split the Double Double and Epsilon Bootis - not something I’d normally bother trying with this scope. 


In summary I feel it was worth doing, it’s made the scope as a whole much nicer to use and the super wide field option gives a whole new kind of observing. 

Edited by SuburbanMak
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  • 1 year later...

Updating this older thread with a great gear combo for the ST80, including here as this one did end becoming a bit of a resource of tips and upgrades for the humble Startravel! 

Having converted to a 2'in focusser and used with a Baader Hyperion 31mm (5.5% field) my ST80 took a bit of a back seat for a while.  Whilst the very wide views were impressive, the level of distortion in the outer 20+% of the field was such that the novelty quickly wore off. 

However, with the addition of a new Stella Lyra 30mm Ultra Flat Field the ST80 is very much back in business.  5.25% and pin sharp across 90% of the field with tolerable distortion in the last 10% - close asterisms stay recognisable right to the edge. It has nice contrast and a good clean field stop, altogether a very immersive and pleasing combo.  (I imagine that for a standard 1.25" focuser equipped ST80, the Stellalyra 24mm UFF would perform similarly pleasingly being of the same optical design & deilver a still wide 3.9% view).   

More use will come also from mounting the ST80 alongside my Mak 127 on the new Skywatcher AZGTiX tracking & GoTo mount.   

All has got me loving my battered ST80 once again :) 

 

 

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Edited by SuburbanMak
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48 minutes ago, SuburbanMak said:

Having converted to a 2in focusser and used with a Baader Hyperion 31mm (5.5% field) my ST80 took a bit of a back seat for a while.  Whilst the very wide views were impressive, the level of distortion in the outer 20+% of the field was such that the novelty quickly wore off. 

However, with the addition of a new Stella Lyra 30mm Ultra Flat Field the ST80 is very much back in business.  5.25% and pin sharp across 90% of the field with tolerable distortion in the last 10% - close asterisms stay recognisable right to the edge. It has nice contrast and a good clean field stop, altogether a very immersive and pleasing combo.

 

Useful to know. I do something similar with my 72mm / 432mm refractor to get a really widefield view. I bought a 2" diagonal (used) and paired that with a Baader Hyperion Aspheric 36mm (new, during the FLO sale). I really like the widefield view but there is edge distortion. I can't decide whether it is bad enough to merit another eyepiece, plus the StellaLyra UFF 30mm would give me a slightly smaller field of view.

My current thinking is that even with widefield, the object in question is mostly towards the centre and so distortion at the edge isn't such an issue. M45 for example looks great widefield because I can see it in context, with near empty sky around it so that the concentration of stars is more obvious.

For the moment that's my reason for not buying yet another eyepiece ...

 

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1 hour ago, PeterC65 said:

 

For the moment that's my reason for not buying yet another eyepiece ...

Fair enough - my reasoning was that it was either try another eyepiece or upgrade the 'scope!  I haven't tried the UFF in my f5 10" Dob yet but am hopeful of similarly improved views there - which would then make his eyepiece amazingly good value, honest (actually at £179 its cheaper than a lot of the other APM UFF rebrands, well done @FLO & I've seen a few reviews where it stacks up very well against the TV Panoptic 27mm - these were all the things I told myself before buying :) 

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1 hour ago, SuburbanMak said:

Fair enough - my reasoning was that it was either try another eyepiece or upgrade the 'scope!  I haven't tried the UFF in my f5 10" Dob yet but am hopeful of similarly improved views there - which would then make his eyepiece amazingly good value, honest (actually at £179 its cheaper than a lot of the other APM UFF rebrands, well done @FLO & I've seen a few reviews where it stacks up very well against the TV Panoptic 27mm - these were all the things I told myself before buying :) 

I have a StellaLyra 30mm UFF  waiting for me when I get home (currently on a cruise 🚢 ). Really looking forward are to trying it out in both 102ed frac and the 12” f/5 newt. I’m sorely tempted to add an ST80 to the fold after reading through this thread for the first time, as I could probably piggyback it onto the 102ed to ride on the AZEQ6, or just on a photo pod on its own. Heck at over 5 degrees I could probably just hold it up to my eye like a giant monocular! 

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