6SE vs. 8SE

So I'm deciding if I should get the Celestron Nexstar 6SE or 8SE. Both are bundle deals from telescopes.com that come with the 17 amp hour battery pack with AC adapter, and the $150 celestron eyepiece and filter kit. The 6SE bundle is $850 and the 8SE bundle is $1230.

I live about 15 miles south of Philadelphia, so the light polution is pretty bad but there are a few places with clear skies not too far away and I'm very interested in astronomy and I know I would get my moneys worth out of either scope. I'm just curious if the extra money would be worth it for the 8SE compared to the 6SE, especially considering the area is light polluted. (Red on light polution map)

My budget is of some concern. I have enough to buy either scope, but if i get the 8SE, I might have to hold out on extra accessories such as dew shield, filters and other things for a while longer.

NexStar 6SE Bundle

NexStar 8SE Bundle

Standby for a flood of comments and recommendations. The conclusion will likely be to get the 8SE if money permits. The extra aperture will be worth the investment.

Rizz,

First, welcome to what I consider to be one of the most helpful, warm and friendly parts of the entire WWW! You will find that any and all of your Celestron Nexstar questions will be answered here in due time, and there are piles of useful tips and instructions for further enhancing your experience with your new scope.

Now to your question. I was in much the same boat as you are when I purchased my 6SE. I had the same issue in that if I got the 8SE I wouldn't have any funds left over to purchase additional equipment to further enhance your viewing/astro photo time. After a few months with the 6SE I have absolutely zero complaints with the scope, and indeed I've had money left over to get a Neximage Webcam, a dew shield, and various other EP's. All in all, I am extremely pleased with my entire set up right now, and have no regrets that I got the 6SE.

HOWEVER, as you will soon find out from others on this forum, the 8SE will capture 50% more light due to the larger aperture. This will greatly improve your viewing of Deep Space Objects such as Nebulae and Galaxies, etc. I will say that 6SE is capable of viewing these objects and I have had success in locating many clusters and nebulas without too many issues. But the reality is that in order for me to truly get the full capabilities out of my 6SE I need to be in relatively clear light pollution-free skies. The 8SE will not need as clear a sky as the 6SE will in order to capture the "feint fuzzies" in harsher light pollution settings due to its greater light capturing qualities.

As far as transportation, I've been told that the weight differential is barely noticeable since both scopes use the same tripod and mount. However, I've confirmed that if you plan on taking the scope on a plane anywhere to travel, you will not be able to fit an 8SE OTA under your seat, whereas I was able to do so with the 6SE.

I will probably at some point upgrade to a larger scope, since aperture fever is about addictive as a good cup of coffee. I think when I do it will be to a CPC, either the 9 or the 11. So don't wonder whether or not you will one day want to get a bigger one. I'm telling you right now, no matter which one you get, you will get aperture fever and WILL desire a bigger scope.

Since I was pretty much a novice when I got the 6SE, I was extremely satisfied with how easy it was to understand the nuances of using the NexStar scope, although the learning curve was a lot easier to deal with thanks to the folks here at the Forum.


Either way you will make a great choice, and keep checking in with the forum for more ideas about how to enhance your experience. Again, I'm not sure there is a more helpful friendly place on the internet.


Clear Skies and Welcome Aboard!

Rizz,

Buy the 8SE.

I had this same decision in June 2009, when I bought my NexStar 8SE. You can buy accessories later. If you get the smaller scope, later on down the road when you have all your accessories in line, you will be telling yourself that you should have bought the 8SE. I have learned over the years that it is best to take an investment (or long-term) approach to a hobby like this. Look at it this way. It will be more expensive to sell the 6SE at a later time and to buy the 8SE. So, buy something that you think you will keep for a longer period of time. It is cheaper in the long run.

The 8SE is a very cool scope! I have carried it onto airlines using one of those 8" SCT padded telescope bags from Orion. The scope in its bag meets the requirements of carry-on baggage size, and it fits nicely in the overhead compartments. I pack my tripod and mount in my checked luggage. I have to disassemble the tripod legs from the mount platform in order to fit into luggage, but that's not a big deal.

You will find on the forums that an 8" telescope is regarded as the smallest scope for deep space observing. Of course, there will be lots of opinions on this. It was just what I found, when I was reading this forum a few years ago. When it comes to deep space objects (DSO), bigger is better. And, the 8" still fits as carry-on luggage, and it is very portable. I can pick up the entire assembled 8SE and walk outside my sliding glass door. I don't have to "assemble" it as I do my 11" SCT CGEM.

Also, in the future, if you buy a CGEM mount (as I did), you can image with the 8" SCT attached to the CGEM. If you read the astrophotography forums, you will find that an 8" SCT is a good match for a CGEM. The focal length of the 8" is not too long, and you can use an F/6.3 focal reducer/corrector to decrease the focal length to 1,260 mm, which is very manageable. I have not seen many people imaging with a 6" SCT. With a size that small, people are imaging with an apochromatic refractor around 130 mm (5.1") in diameter.

Also, you can use the 8SE mount to mount a small 80 mm apochromatic refractor for planetary or wide-field observing while the 8" SCT is acquiring images on a CGEM. I believe that having options with your equipment is very key in this hobby.

So, I think that the 8SE is more versatile for future use as well as an excellent beginner's scope for planetary and DSO observing.


Jamie

The 8SE captures 78% more light (almost twice) than the 6SE, since the light gathering is proportional to the square of the diameters.

I like to stretch my legs on the airplane, so I wouldn't put a scope under the seat. The padded Orion cases are fine for the small, relatively light scope to sit in the overhead luggage compartment on a plane.

Part #15194
http://www.telescope...m&keyword=15191


Jamie

Honestly I would opt for the bigger aperture.
bc

The 6 and 8 use the same mount and the 8 is only slightly larger and heavier than the 6. Total weight on the 8SE is 33 lbs. I think the scope is 11 lbs so the tripod and head are 22 lbs.
It is easy to separate into 3 parts and reassemble.
All IMO; Don T.

Hi Rizz and welcome to the Nexstar forum... When I first joined CN I asked exactly the same question, and I am going to give you exactly the same answer I got.... Buy the 8SE. With the kit that comes with it, it should keep you happy long enough to save for all the other bits and pieces you will want/need. 8 inches is what's called the sweet spot, it gets you to all those deep space objects you read about in books.. The 6SE is an excellent scope but the 8" takes you further.....

Welcome, I had the same question as well when I was looking to upgrade to a goto scope. After searching on here and looking at the pros and cons I, too, opted for the 8SE and I'm very happy I did.

Just a side note I recently purchased the 8SE from the same seller.Please make sure you call to make sure it will all ship at the same time.
Also when you call them ask for an additional discount which will save you an additional $50-$60 which will pay for the dew shield.
Good luck the 8SE is a very nice scope and you will enjoy if the skies permit.

Hello from another newcomer to the site.

I just bought the 6SE from telescopes.com. Price was my limiting factor. Everyone here has given good comments. Yes, I would have rather bought the 8SE, but just couldn't swing it.

As for light gathering, I live in Utah and it's pretty dark here. From my backyard, I can make out the Milky Way. It's faint, but it's there. If I go an hour away into the desert, it's really dark. So I think the 6SE will be fine for me for a long time.

Lot of good info and advice thanks. Still reluctant to get the 8SE though cause I'm a (relatively) broke college student. I know the 8SE would be much better and I would love to have it. I think I'll still need to think about it for a few more days. Thanks

Standby for a flood of comments and recommendations. The conclusion will likely be to get the 8SE if money permits. The extra aperture will be worth the investment.

Hi Rizz24 and a fond welcome to this Nexstar forum of CN !

I've nothing to add to what Eddie has already voiced except to say that as you can see, his prediction of a flood of comments and recommendations, came true.

In full agreement with him therefore: if the money WILL stretch, get the 8SE !

You can make your own dew shield for next to nothing !

Best regards,
Tel

Just to add my

Welcome Rizz24 to our little bit of heaven the Nexstar forum and, of course, CN !

Standby for a flood of comments and recommendations. The conclusion will likely be to get the 8SE if money permits. The extra aperture will be worth the investment.

Exactly - with one rider. If you can afford the 8SE now - then get it, no ifs or buts. Aperture is always king and once you've got the scope you can always save for those absolute "must have" accessories.

The 8SE will allow you to see more than the 6SE - especially when at a dark-sky site - for only a marginal 3lb extra weight & bulk. Although I love my 6SE, I am always whistfully thinking of an 8SE/C8. As the 8 is as far as it goes with the NexStar mount, there is no "I really should have got..." feeling as you are there already.

If the bug really bites, then you are into a heavier mount and/or equitorial with a larger optical tube - say 9.25, 11 or even 14" and then you are talking about a serious investment but, in terms of "best bang for your buck", the 8SE hits the spot.

EDIT: Just clicked on your links and the 8SE is down to $1,199 - get it now!

Hi Rizz,

Welcome to CN's & to the NexStar forum.

Which ever scope you choose, I believe you'll be happy for years to come.

Enjoy & always feel free to ask any & all questions!!

Hi Rizz & Welcome to Cloudy Nights!

the 8SE will capture 50% more light due to the larger aperture

The 8SE captures 78% more light (almost twice) than the 6SE, since the light gathering is proportional to the square of the diameters.

Actually, you need to take into account the size of the central obstruction to compare the amount of light the two scopes receive. The 6SE's central obstruction is 37% of the diameter as opposed to the 8SE's more svelte 31%. If you do the calculations, you'll find that the 8SE in comparison to the 6 has:

92% more light gathering capability
35% more resolution
48% more contrast

If there's any way you can swing the 8SE, go for it. You can always save up for more accessories later. The 8SE only weighs 3 pounds more than the 6, although it is quite a bit more bulky. But the views are noticeably better and it opens up a lot more objects to view. Things that are on the border of perception in the 6SE will show up nicely in the 8.

-Dan

I'm going to go against the grain here. If you can only honestly afford the 6se, then go for it, it is an excellent telescope and you will get years of fun from it. If, in time, you want something bigger, then get a 12" dob.
One of my observing group has an 8se, and I can honestly say that I have never seen any object in the 8se that was massively better than in my 6se. (Another has an 8" Meade LX200, and it's not massively better either.) As long as the scope is properly collimated and you use half-decent eyepieces, you will be fine.

Warm welcome,

i took the same decision a few years ago. Bought a 6SE and a week after changed it for a 8SE, all based on advice from friends with scopes.

It is a good move. The 6SE is fantastic if you can not have the budget for the 8SE. It is a perfect companion to a 10 or 12 inch dob also. The cool down time of the 6SE is smaller which can be an advantage if you have a bigger scope.

Besides that, weight and convenience, tracking etc., it is all the same. Except for a bigger aperture for the 8SE. Which is an advantage everywhere

Putting accessories in the decision is not a good thing on the long run. Get the bigger scope now. Filters? You can easily live without for years. Dew shield, you can make your own.

Once you buy your scope, you add stuff progressively. When you buy accessories or EPs too rapidly, you get stuff you do not need. Take your time. Get the big gun if you can swing it.

If not, the 6SE is a great scope you will have fun with for years.

Allow me to stir it up a bit. I bought a 6SE for portability because I already had an 8" in the form of an LX200R. The 8" is definitely a 75 pound, two piece, 'grab-n-groan' setup. I wanted lighter weight without losing much aperture and the 6SE satisfied the need. However, if it happened all over again it would be just the 8SE, my AT80EDTA, and something bigger, later, and yet to be purchased.

All of the posts you've seen so far are valid and cater somewhat to individual needs and desires. You'll enjoy either one but probably be satisfied more in the long run with the 8SE.

Although I now have the 8se, I too loved the 6se when I had it. It's a great telescope.
The 8se is of coarse, better than the 6se, but if the 6se turns out to be your choice, I'm sure you will be very happy with it for years to come.

Regards. Peter.

Hi Rizz & Welcome to Cloudy Nights!

the 8SE will capture 50% more light due to the larger aperture

The 8SE captures 78% more light (almost twice) than the 6SE, since the light gathering is proportional to the square of the diameters.

Actually, you need to take into account the size of the central obstruction to compare the amount of light the two scopes receive. The 6SE's central obstruction is 37% of the diameter as opposed to the 8SE's more svelte 31%. If you do the calculations, you'll find that the 8SE in comparison to the 6 has:

92% more light gathering capability
35% more resolution
48% more contrast

If there's any way you can swing the 8SE, go for it. You can always save up for more accessories later. The 8SE only weighs 3 pounds more than the 6, although it is quite a bit more bulky. But the views are noticeably better and it opens up a lot more objects to view. Things that are on the border of perception in the 6SE will show up nicely in the 8.

-Dan

When calculating the ratio of areas between two scopes, it is accurate enough to ignore the obstruction. For resolution it is necessary to use the central obstruction.

However, if you would like to know the ratio of the areas including the central obstruction, you will calculate the exact same number if you ignore the central obstruction in the case that both scopes have the same central obstruction percentage. You can see this algebraically. In this case the central obstruction is not the same.

Your calculation of 92% more light-gathering capacity is not correct. If you calculate correctly, you will find that the 8SE gathers 86% more light than the 6SE, which is within 4.3% error of the calculation from ignoring the central obstruction -- accurate enough. I used the central obstruction numbers from Celestron's website under specifications.


Jamie

Hi, Rizz24,

First, welcome to our forum. You'll find lots of help here if you need it, from folks who are happy to have such great telescopes, either 6SE or 8SE. If you have questions, ask away!

A little history... For decades, the standard amateur astronomy telescope was a 6" f/8 Newtonian reflector. It was a big deal to have something bigger.

Gradually, probably beginning with the Dobsonian "revolution" in the early '70's (?), larger scopes became more readily available. There aren't as many people making their own scopes anymore, as was common in the 40's and 50's, because it is almost as economical to buy one. Today, 8" reflectors and Schmidt-Cassegrains have become fairly standard for backyard observers.

But, also, GoTo technology has made it easier to find things in the sky (without getting into a discussion about the "purity" of star-hopping). If I were just starting out, and had a limited budget, I think I would recall that 6" aperture kept thousands of amateurs happy for decades. I would be happy to have a really good scope that would show me most of what a somewhat larger one would and would enable me to learn the sky and the telescope "biz" well.

If you can manage the extra money for an 8", then go for it. But, especially if you're just beginning, the 6SE is a wonderful way to get started and will keep you busy for years. (However, as mentioned by others, you can get by without filters -- I rarely use one on my 8SE - and you can improvise a dew shield.)

(Have you considered a used 8SE?)

You will not regret getting a 6SE.

Whatever you do, stay in touch here. Be sure to submit a "first light" report.

- Tony

Either of the two will provide good views. I would go for the 8 if you can but if you get the 6" know that you are getting a good scope and not making any major sacrifice. Don T.

Bought the 8" from the same vendor and have no regrets. It will hopefully be a lifetime investment and accessories will always be there. My sky is light polluted and I can say the 8 allows me to see many things I wasn't sure I would be able to. The package is great and aside from dew shield and heater(in the muggy south) and a observing chair my best acccessory is an understanding wife. Get that accessory and you'll be happy with either scope.

Hi Jamie:

When calculating the ratio of areas between two scopes, it is accurate enough to ignore the obstruction. For resolution it is necessary to use the central obstruction.

However, if you would like to know the ratio of the areas including the central obstruction, you will calculate the exact same number if you ignore the central obstruction in the case that both scopes have the same central obstruction percentage. You can see this algebraically. In this case the central obstruction is not the same.

Your calculation of 92% more light-gathering capacity is not correct. If you calculate correctly, you will find that the 8SE gathers 86% more light than the 6SE, which is within 4.3% error of the calculation from ignoring the central obstruction -- accurate enough. I used the central obstruction numbers from Celestron's website under specifications.

You're absolutely right that the difference between 92%, 86%, and 78% is not all that significant. Especially in view of the fact that the eye's response is not linear.

However, I think if you go through the calculations, you'll find that 92% is the correct ratio. Using numbers from Celestron's web site:

The 8SE has an aperture of 203.2 mm or 8", which yields a full area of 50.265 sq in. The central obstruction is 31.3%, or a diameter of 2.504". Its area is 4.924 sq in which leaves the 8SE with a clear aperture area of 45.341 sq in.

The 6SE has an aperture of 150mm or 5.91" which yields a full area of 27.432 sq in. The central obstruction is 37.3%, or a diameter of 2.204". Its area is 3.817 sq in which leave the 6SE with a clear aperture area of 23.615 sq. in.

If you divide the 8SE clear aperture area by that of the 6SE, you get 1.92 for an increase in of 92%. And, while it isn't a very big difference from the numbers you came up with, it just sounds better!

-Dan