RobertI

There's a lot of observing of Mars, Jupiter and Saturn going on at the moment with different scopes, so I read with interest an article on the Kunming United Optics website about the factors affecting contrast delivered by a scope and hence its ability to see low contrast detail on planets. In summary they stated the following factors affecting contrast, in descending order of importance:

1. Seeing conditions (or air turbulence) - the single most important factor that adversely affects image contrast when seeking planetary detail through a telescope.
2. Optical figure
3. Collimation
4. Optical smoothness
5. Baffling
6. Central obstruction - and only noticeable when central obstruction goes beyond 25% by area. Note that the increase in central obstruction is rated as the smallest contributor adversely affecting contrast.

I note they do not mention glass type as a factor, although later in the article they say chromatic aberration reduces contrast on planets, so perhaps it's not such a good article after all! They also don't mention anti-reflection coatings, but perhaps that's because pretty much all scopes are multi-coated nowadays?

Anyway the interesting takeaway for me is that central obstruction has the least effect of all.

Sounds wonderful, thanks for sharing. Well done on getting some clear skies and good seeing - I’m getting desperate! 😉

54 minutes ago, Victor Boesen said:

Thanks a lot Rob! Will have a read through your thread and contact widescreen tomorrow. They all look like really nice scopes! I started out thinking the Evostar 100ED was the hands down best choice for me, but the sliding dew shield, focuser and wider FOV of the Altair, TS and technosky looks really good!

I will keep this thread updated;)

Looking forward to updates. You should be able to track down 'first light' reports and observing reports using the AA 102 ED-R from myself, @Paz and @Dantooine - I'm sure there are plenty of other owners on SGL too!

I very nearly bought the very same scope (from a different vendor)! My tale is described in this thread.  I had a long chat with the vendor who was very helpful and confirmed that the TS-optics, the Tecnosky and the Altair Astro ED-R are identical and made by Kunming Optics. Why TS advertises Lanthanum and the other two don’t, I’m not really sure - would be interested to hear what Widescreen day on that. The Tecnosky is an Italian brand, a bit like Altair Astro. I ended up buying the Altair Astro, but only because they were closer to home, having a shop about 50 miles away. I’m sure the Tecnosky would be the same quality. I haven’t had the chance to use the scope much yet, but it is clearly a high quality scope and has given me some excellent views of Mars and surprising DSO ability. I’m really glad I went for F7, it’s so much easier to use than my 100mm F10 achro, and gives much better planetary views. Also better wide field ability. Really happy with it and dying to get out again! I did have to ‘re-align’ my expectations, FPL-53 does not turn a 100mm scope into a 150mm scope, but the quality emerges over time as you use the scope more and more, and really shines in good seeing conditions and dark skies. Good luck and keep us up to date. 

Yeah, I hope the wifi works well. I forgot about the belt drives, another tick in the box - old school on steroids!

Great video Chris, looks like a very well speced mount for the money, very solid and well put together. It seems to be quite ‘traditional’ in concept (eg: the bolt and safety screw on the saddle, which I personally like from a safety POV, but is quite ‘old school’) but I like the 2” tripod and heavy counterweights - says that this mount means business! Seeing you putting all the different pieces together made me realise how convenient something like the Celestron EVO Mount is with everything built in, but obviously a very different proposition, not an observatory mount, and you can’t buy it without the scope!

Looking forward to seeing how the EXOS-2 does in the field! 

17 minutes ago, johninderby said:

Fitting a Baader Refractor Steeltrack to my CC was a big improvement as not only a better focuser than stock but has a much greater travel and have never needed to use the extension tubes.🙂

Nice upgrade. How have you found the views compared an SCT?

I've been very impressed with my RC for imaging, very well made, superbly baffled, nice crayford focuser, very sharp images. A CC should be very nice for visual. Obviously doesn't have the huge focus range and enclosed tube of the SCT but I would hope the views would be sharper? Thing is though, if going for a mirrored scope, wouldn't a newt with a smaller secondary be a better bet? 🤔 (sorry if I'm diverting the thread)

Welcome

17 minutes ago, Adreneline said:

I think (maybe?) I got the first one - never been a trailblazer before. I wanted one of these and was offered the StellaLyra - only difference being the colour (doesn't matter in the dark) and the name on the side. I understood they were soon to be added to the FLO site.

Ah, thought it might something like that! Based on the well regarded GSO RC I think (I also have one). 

Is this a wind up? 😂😂

3 minutes ago, Dinglem said:

@fwm891 not seen that on the @FLO website!!

Me neither! 😮

I have used filters for viewing planets and the jury is out for me.  I think they could make a difference for certain people under certain conditions if doing some really critical observing over an extended period, but so far for me, not really definitive.

This is an excellent guide: https://agenaastro.com/articles/guides/visual-and-imaging-filters/choosing-a-color-planetary-filter.html

It appears to particularly recommend the following filters for Mars:

• #12 Yellow - Good for Maria, Atmospheric clouds
• #23A Light Red - Maria and surface, Dust clouds, Polar caps

The first one has 75% transmission and is good for smaller scopes, the latter has only 25% transmission so better for 6" and above. 

Edit: Having just read the linked article by Bill Paolini, I feel there is little point in reading the information I linked to above! 

6 hours ago, Mr_Simnock said:

Have you bought an extender at all for it to get focus with certain eyepieces? I can't reach focus with any of my eyepieces till my diagonal turns up next Monday but I do feel something to extend things by about 20mm would help a lot, anyone any suggestions?

I’m afraid I can’t help with any extender recommendations as I don’t do straight through observing, but I can confirm it has worked fine with all of my eyepieces from 5mm to 38mm with a 2 “ diagonal. 👍

1 hour ago, mikeDnight said:

I've shown this refractor before, but not with an Extender-Q attached, turning it from F8 to F12.8

Nice eyepiece too!

35 minutes ago, Space Hopper said:

Still had no news from Astrotrac regarding dispatch, delivery.

I was told it was to be with me by the end of September, and i'm not optimistic.....

Very disappointed with all this.......

You must be incredibly frustrated. I was going nuts waiting for 'just' two months for my new scope to arrive (I gave up in the end and ordered something else), so you must be beyond the end of your tether. Looking on the bright side, I guess it's good news that someone on CN has received one and it seems to be working really well (ignoring, for the moment, the question of why they got it before you), so hopefully it's not a question of IF you will receive it, but WHEN.

I’m happy with Skytee, it’s a very solid mount and has handled all the scopes in my signature with no problem, some of them in windy conditions. I usually use it on a 2” tripod which makes the whole thing heavy, but solid, and still liftable. I tried the Skytee on my lightweight aluminium tripod and it was far too wobbly unless I used a short scope at lower powers. The best option is probably the 1.75” tripod. The Skytee has also has slo mo controls which I find essential, but many people don’t, preferring to push. Build quality of the Skytee is not the best though and you’ll need to spend extra on an ADM saddle as the stock ones are rubbish (or at least always were). Second hand might make more sense. 

5 hours ago, Mr_Simnock said:

Joined the club today, mount won't be with me for another week though

Recently got one myself - only managed to use three times to date but am increasingly impressed each time. 

Superb sketeches Mike and a very interesting comparison. I have really enjoyed observing sessions where I have had the C8 and the Tal 100RS side by side, it adds an interesting additional perspective to observing. Under good conditions the C8 easily outperformed the Tal (or at least MY Tal!) on Jupiter and the moon (but not on doubles). I now have an ED100 and am really looking forward to doing a side by side with the C8 on Mars.  

Wonderful image, spent an enjoyable 20 minutes looking at the detail in that one. Some interesting galaxies too. There's an interesting looking object in the spiral arms, don't think it's a globular cluster, could be a galaxy seen through the spiral arms?

Might be a face on spiral?

Great report, and uplifting too, glad you got your mojo back. It's amazing how our memories can play tricks when it comes to remembering what our equipment can do. I often read back through my old reports and am suprised what I have been able to see through my scope, particularly the smaller ones.

54 minutes ago, Pryce said:

I needed to start over.. Again. So I ordered myself a EQ6-R, 72ED and all the extra bells and whistles.

EQ6-R and 72ED? No, no, that's no good, what you really need is....<insert name of even better mount and telescope here>.

I find focussing on mine is fine with a 1.25" diagonal but problematic with a 2" diagonal (I think the same problem everyone else is referring to?). The Hyperions work fine as they can sit further inside the diagonal, but the BST 5mm is too close even with a low profile 2"/1.25" converter, it can JUST reach focus but there is no room to go any further, so not really suitable for fine focussing back and forth. 

14 minutes ago, markse68 said:

off topic question but i’ve noticed on old threads that get resurrected or referenced there’s an absence of likes etc- was that feature added later or were astronomers different back then?

Interesting question, perhaps the mods can answer. I suspect if you go back far enough it just hadn't caught on in forums such as this, also fewer members perhaps?

52 minutes ago, wookie1965 said:

Did anyone know there are  different focusers on the Tal 100rs 

There is this one https://www.astrobuysell.com/uk/propview.php?view=166309

But on mine its totally different mine has a rotating ring so I can turn the diagonal around then lock it in place.

Yes mine is like yours but with a different knob. There was a long thread about the different Tal 100 focusers, all I could find was this, but there is a longer one somewhere and the conclusion I believe was that there were at least four types of Tal100 focuser!