Best planetary telescope for my or an individuals needs.

[Louis D]

16 minutes ago, vlaiv said:

I'm only mentioning it because it was on the list of possible scopes in the initial post. In my view, except for the high end ED refractor (or triplet) which is not considered both because of price and bulk, this scope will give best views of the lot. Every other design is compromise in some respect.

The OP could start with an f/5 Newtonian and replace the secondary with an undersized one if contrast is more important than full illumination.  I can't find any 6" f/8 Newt OTAs under 14 pounds.  Is it just the extra tube length adding 4 pounds?

[vlaiv]

1 minute ago, Louis D said:

The OP could start with an f/5 Newtonian and replace the secondary with an undersized one if contrast is more important than full illumination.  I can't find any 6" f/8 Newt OTAs under 14 pounds.  Is it just the extra tube length adding 4 pounds?

https://www.orionoptics.co.uk/VX/vx6-6l.html

OO UK say that their VX6L weights 5kg which is 11 pounds.

[Guest]

3 hours ago, Stu said:

@Grumpy Martian what scope/s do you currently have? I seem to remember you’ve had a few which would likely give good planetary views. I think a lot of the time it is the sky conditions that determine image quality as much or more than the scope itself. As an example I’ve had very credible and enjoyable views of Mars through my Heritage 150p, a cheap f5 newtonian with plastic helical focuser!

Personally I think you can’t go too far wrong with a decent 4” apo refractor, they generally deliver good views even when conditions are variable. The ED100 may be a bit long to be convenient, so perhaps an f7 from TS or similar.

Alternatively, how about the Bresser 127mm Mak, which is a true 127mm rather than the 119 of the Skywatcher, they get good reviews.

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-mc-127-1900-maksutov-cassegrain-ota.html

Or, how about the new StellarLyra 6” Classical Cassegrain? This would avoid the cool down issues of a mak and should give great views.

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-mc-127-1900-maksutov-cassegrain-ota.html

Thanks Stu. I currently have an 80 mm Equinox and an Otion Optics 6 inch f5 Newtonian. These give good views of the planets. But not that crisp contrasty view that I know can be achieved and have seen before. It may be that the skies and seeing conditions has deteriorated over the years. Looking for something not exceeding 4.5 kgs and is not too long

[Guest]

I am grateful for all of the input. I have considered a Celestron C6. But not sure how they perform on planets.

[Louis D]

1 hour ago, Grumpy Martian said:

Thanks Stu. I currently have an 80 mm Equinox and an Otion Optics 6 inch f5 Newtonian. These give good views of the planets. But not that crisp contrasty view that I know can be achieved and have seen before. It may be that the skies and seeing conditions has deteriorated over the years. Looking for something not exceeding 4.5 kgs and is not too long

The 80mm Equinox should be providing crisp and contrasty views if allowed to properly acclimate.  My 90mm triplet APO takes 30 minutes to an hour to acclimate.  It's kind of a mess before that.

Try downsizing the secondary in the Orion 6" f/5 Newt to 30mm in diameter or so to get to a 20% by diameter obstruction.  The level of contrast at that point rivals APOs with zero false color.  You're just left with spider diffraction spikes, but curved vanes can spread out the spikes to make them less noticeable if they bother you.

[mikeDnight]

Martin, may be you should take a look at the video on the Technosky refractor thread on this forum. It's a small but impressively capable 102mm ED that could be worth considering.

[dweller25]

I have a bad back and find viewing from the back of a scope and sitting down to observe is best.

[Stu]

1 hour ago, dweller25 said:

I have a bad back and find viewing from the back of a scope and sitting down to observe is best.

Yep, if you get the scope up reasonably high, with an adjustable seat it can be very comfortable.

[AdeKing]

14 hours ago, Stu said:

I’m mindful of the fact that Martin had a lovely Vixen 115mm apo previously and didn’t get in with it, I think for ergonomic reasons so the 120ED would be similar or worse. I agree the 6” CCs could be a good compromise.

Yes Stu, Martin previously owned the ED120 that I currently have and passed it on to me due to the aforementioned issues with weight and discomfort with his ribs when viewing through it.

It's a shame the weight and length cause Martin issues as I've had some cracking planetary views through it this year, particularly of Mars.

[RT65CB-SWL]

11 hours ago, Grumpy Martian said:

I am grateful for all of the input. I have considered a Celestron C6. But not sure how they perform on planets.

C6/SCT or C6N...? 

I have the C6/SCT and viewing Mars with a TeleVue 6mm Radian is pushing both to the limit. 

[Guest]

Stu has probably hit the nail on the head with this one. That being the condition of the skies and seeing condition.

Years ago the street scene was quite dark, not much lighting. Today everywhere is lit up. Go to  central London and you would'nt know if it was night or day with all the illumination. Buildings lit up.Exhaust particulants in the sky being illuminated This goes for most of our towns aswell. So it's no wonder I feel that it is differcult to get the sharp contrasty views from a telescope that seemed more frequent in past times. Ah well.

Edited October 14, 2020 by Guest
Added text.

[Moonshane]

I sometimes find the position more comfortable with a frac if I look 'side on' rather than from the back. The angle of the object can be a bit odd of course but the detail is the same.

I prefer sitting too.

[nfotis]

On 13/10/2020 at 18:48, Grumpy Martian said:

Heavy to lift onto a mount

 

I guess that this means that both the Skymax 150 and the classical Cassegrain 6" are out, then.

I would suggest the Bresser 127/1900 Maksutov, then, since it offers long focal distance and light weight at f/15.

https://www.bresser.de/en/Astronomy/Telescopes/BRESSER-Messier-MC-127-1900-OTA-Optical-Tube.html

N.F.

[John]

12 hours ago, nfotis said:

 

...I would suggest the Bresser 127/1900 Maksutov, then, since it offers long focal distance and light weight at f/15.

https://www.bresser.de/en/Astronomy/Telescopes/BRESSER-Messier-MC-127-1900-OTA-Optical-Tube.html

N.F.

I've eventually reached that conclusion through a process of elimination !

I do think that observing conditions and the location of the targets are part of this story though.

Under good steady conditions with the target planet well placed (eg: with Saturn and Jupiter somewhat higher than they are now) I've had really amazing views of the planets with a wide range of telescope designs, even ones that are not supposed to be planetary specialists

Edited October 15, 2020 by John

[scarp15]

As John has mentioned above, observing conditions and location of the target are crucial. I began observing Mars from midnight last night, the image was not that stable to begin, perhaps roof thermals were partly to blame. Later as Mars culminated due south and my observing aspect was entirely unhindered by buildings the image became - intermittently, more stable and I was able to increase the power a little and gain more surface detail, texture and hints of ochre shading in the northerly region. This was using an OOUK VX8L (F6) on dobsonian base and seated on an adjustable observer's chair. A set of capable eyepieces you enjoy using at the optimum lowest power is just as applicable.