I need some advices for the eyepieces

[Baldor]

Hello, I just registered here. I'm new in this and I wanna know what to use for best results. My telescope is Bresser National Geographic 114/900 AZ. I already used it for a few months and I got good views of the Moon, Jupiter and his moons (but kinda blurry cuz it's difficult to focus), some good views of Saturn and blurry Mars. The eyepieces that i have are erecting eyepiece 1.5x, barlow lens 3x and the other eyepieces are H25mm (idk what's H here), H9mm, SR4mm (idk what's SR here again). So I'll be glad if someone can help me what combinations to use for the Moon, planets, galaxies and etc. Sorry if I didn't explained something good, English isn't my first language. I'm open to questions if you need more information and thanks! 

[domstar]

The good news is the H means it's a Huygens design. This means that even a cheap eyepiece upgrade will give you a huge improvement. They came included in the box of my first scope and when I upgraded to second hand Skywatcher plossls that came with their scopes, I couldn't believe the difference. 

A lot of people will tell you to spend around 50 pounds for Starguiders, which have a great reputation here and I have one myself, but if you don't want to spend so much, cheap second-hand plossls will improve thing a lot. On the negative side, if you get a better scope you'll feel the need to upgrade the eyepieces again but they are so cheap it doesn't matter.

[Baldor]

8 minutes ago, domstar said:

The good news is the H means it's a Huygens design. This means that even a cheap eyepiece upgrade will give you a huge improvement. They came included in the box of my first scope and when I upgraded to second hand Skywatcher plossls that came with their scopes, I couldn't believe the difference. 

A lot of people will tell you to spend around 50 pounds for Starguiders, which have a great reputation here and I have one myself, but if you don't want to spend so much, cheap second-hand plossls will improve thing a lot. On the negative side, if you get a better scope you'll feel the need to upgrade the eyepieces again but they are so cheap it doesn't matter.

Thanks for the reply! In future I may think about better eyepieces, but for now I wanna learn how to use these. And also I'll be glad if you can tell me which eyepiece or combination of eyepieces to use depending on the objects.

[domstar]

Sorry, I should've read it more carefully.

I always start with the eyepiece with the longest focal length (biggest number) because it has the least magnification and shows the most sky. When you have the object centred, you can try and up the magnification. The H25 should work OK with the Barlow but the other eyepieces will probably be too strong for it. The 4mm probably won't be very useful (too much magnification) and the erecting eyepiece is only for use during the day (looking at birds). 

So, 25mm mostly but up the magnification by using the 9mm or the Barlow to get more magnification on the moon or planets. Mars can be a disappointing devil in a small scope unless the conditions play ball.

Anyway, good luck, have fun and welcome to the forum.

[rwilkey]

25 minutes ago, Baldor said:

And also I'll be glad if you can tell me which eyepiece or combination of eyepieces to use depending on the objects.

Hi there, when stargazing always start with the 25mm eyepiece as that helps you find objects and once you have found something use the 9mm to view it better, this gives you 100x magnification, which is the optimum for this telescope.  You will find the 4mm almost impossible to use, so don't worry about this one, it is not very good.  I think the SR stands for 'Synchronized Ramsden', another early design of eyepiece like the Huygens.  The Barlow Lens will be mostly of no use at all.  Good luck and clear skies!

Edited October 2, 2020 by rwilkey

[Baldor]

5 minutes ago, domstar said:

Sorry, I should've read it more carefully.

I always start with the eyepiece with the longest focal length (biggest number) because it has the least magnification and shows the most sky. When you have the object centred, you can try and up the magnification. The H25 should work OK with the Barlow but the other eyepieces will probably be too strong for it. The 4mm probably won't be very useful (too much magnification) and the erecting eyepiece is only for use during the day (looking at birds). 

So, 25mm mostly but up the magnification by using the 9mm or the Barlow to get more magnification on the moon or planets. Mars can be a disappointing devil in a small scope unless the conditions play ball.

Anyway, good luck, have fun and welcome to the forum.

Thanks very much! I learned some of this the hard way, but you also helped. Thank you once again! 

[Louis D]

3 hours ago, Baldor said:

H25mm (idk what's H here), H9mm, SR4mm (idk what's SR here again)

H = Huygens, SR = Symmetric Ramsden.  The difference between a Ramsden and a symmetric Ramsden is the former uses two different lens elements while the latter uses two of the same element.

Note the various eyepiece designs in the diagram below:

The above Ramsden is pretty close to symmetric as opposed to the one in the following diagram where one lens is clearly larger than the other:

Symmetrics, whether Ramsden or Achromat Pair, are cheaper to make than asymmetrical designs (such as true Plossls) because you only need to make half as many unique lenses or lens pairs.

[Alan64]

Welcome Baldor,

This is your kit...

https://www.bresser.de/en/Astronomy/Telescopes/NATIONAL-GEOGRAPHIC-114-900-Reflector-Telescope-AZ.html

I have a 114mm f/8 Newtonian, too, a 114/900...

Both are very nice telescopes, but the eyepieces and barlow that were included with my own are not very good, not at all.  The images through the eyepieces are grainy, as though a fine lattice-like grid was laid over the images.  The barlow introduced false-colour to boot.  Hopefully, you can make use of the 1.5x erector-lens during the day; for birds in trees, ships at sea, et al.

At f/8, and with a long tube, you won't need expensive eyepieces for a good showing.  The ones included with your kit will be fine in the beginning.  With entry-level kits like our own, we got a good, a very good, telescope, but often the included eyepieces and accessories fall short of that, and I as found out.

Plossls ranging from 9mm to 32mm would make a fine set for the telescope, along with a quality 2x barlow perhaps; not a 3x.  Plossls are the minimum in performance-eyepieces, the minimum standard currently, and are reasonably priced; cheap even, in other words.

Being a Newtonian, you'll want to check the collimation of the telescope; any telescope upon its arrival for that matter.  If it's mis-collimated due to either factory-neglect or during its shipment and handling from mainland-China, then being at f/8 there will also be the bonus that collimating it will not be as difficult as with a shorter f/5 or f/4 Newtonian.  You will also enjoy the benefit of a smaller secondary obstruction, just like that of my own...

As a result, the images will be slightly sharper and more contrasty.

Incidentally, Meade and Bresser are subsidiaries of the same parent-company.  Therefore, it is likely that both of ours were made in the same brick-and-mortar factory even.

Enjoy your new kit.

[Louis D]

@Alan64I thought Bresser is the European marketer of JOC products as Explore Scientific is in the US while Ningbo Sunny out-right owns Meade.

[johninderby]

Bresser is not a subsidiary but a majority German owned company 60% owned by Rolf Bresser and  Helmut Ebbert and JOC owns 40%. Meade no longer owns any part of Bresser.since the management buy out. Bresser also is a manufacturer as well as importing JOC made scopes.

Bresser does distribute Explore Scientific and Lunt in Europe.

Bresser now has it’s own US distribution company for Bresser products in the US.

 

Edited October 5, 2020 by johninderby

[Alan64]

1 hour ago, Louis D said:

@Alan64I thought Bresser is the European marketer of JOC products as Explore Scientific is in the US while Ningbo Sunny out-right owns Meade.

My bad, yet both are manufactured in mainland-China, at least; apples and oranges in the end.

Edited October 5, 2020 by Alan64

[Alan64]

1 hour ago, johninderby said:

Bresser is not a subsidiary but a majority German owned company 60% owned by Rolf Bresser and  Helmut Ebbert and JOC owns 40%. Meade no longer owns any part of Bresser.since the management buy out. Bresser also is a manufacturer as well as importing JOC made scopes.

Bresser does distribute Explore Scientific and Lunt in Europe.

Bresser now has it’s own US distribution company for Bresser products in the US.

 

Yes, I suspected that JOC manufactured my only ES telescope.  

[johninderby]

Think most of Bressers scopes are made for them by JOC but Bresser is a big company and astro stuff is only a small part of what they do. Bresser makes everything from weather centres, 3D printers and  photo studio gear etc. 

Bresser does a lot of design and developement work so probably helps JOC in that capacity.

Edited October 5, 2020 by johninderby

[RT65CB-SWL]

Добър ден 🇧🇬 / Good day 🇬🇧 @Baldor and welcome to SGL. 

If your 'scope accepts only 0.965" eyepieces, there are adapter's that can adapt to 1.25"
Prices start from about £6.00GBP / ЛВ12.94GBN - note: currency conversion as at time of posting.

To give you an idea of the size... below is an image of my 0.965" Ortho and a 1.25" adapter...

and the small squares on the mat are 12.5mm. 

[Alan64]

Huygenian and Ramsden designs do conjure up visions of the older, Japanese .965" format, but thankfully the OP's telescope is configured for the 1.25" standard.

Incidentally, I found this interesting...

https://www.oxfordreference.com/view/10.1093/oi/authority.20110803095952307

...the original for f/10 and longer, and the modified down to f/8, at most, so perhaps the latter was included within the kit.

[Spacecake2]

Always start with bigger focal lengths to find the object. 25mm could be used for wide shots of the moon. 9mm are suitable for viewing saturn and jupiter and you will find that your 4mm will be useless. It gets easy after some experience.

Goodluck!