Overall length of Skywatcher Explorers

[Plumb71]

Hi 

Does anyone know the overall length of the Skywatcher Explorer 150p and the 150pl please, i have emailed Telescopes shops and they give me either the focal length,  that the 150pl is 250mm longer? I need to know before i buy for storage reasons thanks

[Cornelius Varley]

Orion (same telescopes, different brand name) give the length of the 150P tube as 26.5" (673mm) and the 150PL 45.5" (1156mm).

[Ronclarke]

I think the 150P is 1000 mm as the shorter 150 PDS is 750 mm FL !!

 

Ron

[Cornelius Varley]

23 minutes ago, Ronclarke said:

I think the 150P is 1000 mm as the shorter 150 PDS is 750 mm FL !!

 

Ron

The 150/750 and 150PDS both have the same focal length (750mm). The 150P tube is 673mm long and the 150PDS with be slightly shorter due to the shorter distance between the primary and secondary. The 150PL has a focal length of 1200mm and is 1156mm long. Information for the overall lengths of both tubes taken from the Orion website.

[Anthony1979]

150p is 750

[Plumb71]

Hi all just recieved an email back from Harrison Telescopes and they say the 150pl is 250mm longer than the 150p this seems to contradict some replies???

[Cornelius Varley]

12 minutes ago, Plumb71 said:

Hi all just recieved an email back from Harrison Telescopes and they say the 150pl is 250mm longer than the 150p this seems to contradict some replies???

Orion say otherwise. In the case of the 200/1000P Explorer and the 200/1200P Skyliner the difference in the lengths of the tubes is about 250mm (230mm actually). Check out the Orion website Telescope.com for their equivalent products. Orion's telescopes are sourced from Synta who are the manufacturers of the Skywatcher brand.

[Ronclarke]

150PL has a FL of 1200  (F8) 150PD and PDS is 750 (F5) according to FLO's advertising!

Edited July 31, 2019 by Ronclarke

[John]

I think the original poster is interested in the physical lengths of the scopes rather than their optical focal lengths.

 

[vlaiv]

5 hours ago, Cornelius Varley said:

Orion (same telescopes, different brand name) give the length of the 150P tube as 26.5" (673mm) and the 150PL 45.5" (1156mm).

This makes sense. I don't know exact numbers, but we could do some math to arrive to approximate figure.

For 150P and F/5 scope, FL is 750mm. Focal point of such scope will be about 150mm away from outside tube walls - sw has about 60mm high focuser, it needs to be racked out a bit to reach focus and there is at least 50mm 2" to 1.25" adapter.

There is additional 75mm distance between secondary and tube wall, so total distance between mirrors is about 525mm.

Beginning of the tube to optical axis of focuser I would say is about 120mm, main mirror is about 15mm thick and there is another 20mm of main mirror cell and back of the tube. If we add all these together - 120+525+15+20 = 680. That agrees with said 673mm very well.

Similar calculation can be done with 150PL and I think we will get close to it's quoted length of 1156mm. It's got 1.25" focuser so focus position will be closer, and distance to the top of the tube probably a bit less.

[Anthony1979]

Its 750mm i own one

[Plumb71]

8 hours ago, John said:

I think the original poster is interested in the physical lengths of the scopes rather than their optical focal lengths.

 

Yes indeed i do wish to know the overall lengths rather that focal lengths, i find it strange that these dimensions on most telescopes are not given, considering that the explorers that i am interested in,500mm is quite a big difference.

To everyone who has replied thanks for you input. Although i am still clueless about which one to get, they both tick boxes for me, i am interested in both planetary and deep space. Would a 150p with a more powerfull eyepiece suffice or a 150pl with a less powerfull eyepiece do the same as the 150p

Im very confused ( i think i have had information overdose) 

Once again thanks for the help

[Cornelius Varley]

4 hours ago, Anthony1979 said:

Its 750mm i own one

Did you measure the overall length of the tube ?

[Cosmic Geoff]

1 hour ago, Plumb71 said:

To everyone who has replied thanks for you input. Although i am still clueless about which one to get, they both tick boxes for me, i am interested in both planetary and deep space. Would a 150p with a more powerfull eyepiece suffice or a 150pl with a less powerfull eyepiece do the same as the 150p

FYI a long focus Newtonian is considered to be somewhat more suitable for planetary use as it has a smaller central obstruction. The longer focal ratio will also make the choice of eyepiece type less critical.  On the other hand, for deep space use the maximum field of view available will be less.  Either f5 or f8 will attain any desired magnification with suitable eyepieces.  f8 Newtonians are now rare as they rapidly become impractical in larger sizes.

If you are really worried about storage space, a 6" Schmidt-Cassegrain will give you long focal length in a short tube - at a substantial extra cost.

Edited August 1, 2019 by Cosmic Geoff

[Ricochet]

2 hours ago, Plumb71 said:

Although i am still clueless about which one to get, they both tick boxes for me, i am interested in both planetary and deep space.

If it is for visual use I would recommend either the Dobsonian Skyliner 150p or the (shorter) Explorer 150p on an AZ4. Don't get an eq mount for visual. 

[Cornelius Varley]

2 hours ago, Plumb71 said:

Yes indeed i do wish to know the overall lengths rather that focal lengths, i find it strange that these dimensions on most telescopes are not given, considering that the explorers that i am interested in,500mm is quite a big difference.

To everyone who has replied thanks for you input. Although i am still clueless about which one to get, they both tick boxes for me, i am interested in both planetary and deep space. Would a 150p with a more powerfull eyepiece suffice or a 150pl with a less powerfull eyepiece do the same as the 150p

Im very confused ( i think i have had information overdose) 

Once again thanks for the help

By measuring my own C6N. I can confirm that the 150/750 is 673mm long.

[Plumb71]

Thanks for all your replies, much appreciate you all giving your advice to a newcomer, i have decided to go for the Explorer 150p. With a new telescope do i need to purchase a collimator? 

[Alan64]

I realise that it's more costly, but in the long run I'd choose the 150P-DS...

https://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-ds-eq3-2-eq3-pro-goto.html

You'd get a better, two-speed focusser, for finer focussing, and if you'd like to take photographs with it in future it'll be good to go; a 150P is not suitable for DSLR-astrophotography, although you can manage afocal-photography, and EAA-photography perhaps.

In so far as collimation...

https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html

...and/or a Cheshire...

https://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html

Edited August 2, 2019 by Alan64