Why not newtonians?

[weixing]

Hi,

want a newtonian for my next scope.
mainly because:
1. best aperture:$$$$
2. better for dso
also because:
3. better viewing
4. i've a st102 az. can still fit an 8"SN+EQ in my car trunk
5. my usual viewing location is <50m from my storage location - hmmm... i think i still like to build a permanent observatory with fixed pier and all

so... any one taking order for lxd75 8" s-n?

Wow... envy you.. Then you should aim for a Newtonian larger than 8"... at least 10" and above.

Anyway, I think another reason that newtonian is not popular is that newtonian give a low technology feeling and also low on publicity.

There are always somebody talking about new achromatic refractor that is as good as a apochromatic refractor at a fraction of cost, the xxx brand new apochromatic refractor is better than the yyy brand apochromatic refractor, the SCT use a new coating that enhance the transmission to a 9x%, the new MCT give a view as good as an apochromatic refractor and etc.... But nobody is talking about newtonian.... since newtonian had basically unchange from the 17th century.

Also, may be we never recommend newtonian to anyone, especially when someone ask about what scope to buy... our answer nomally is refractor, SCT and MCT... but seldom see people mention newtonian. So may give an impression that newtonian is no good.

It may also because newtonian require collimation and collimation seem to be very difficult... at least that is what I think before I get my 6" F5 newtonian.

Have a nice day.

[gwenyi]

heh. we should have a newtonian with zambuto mirror. it will become the next scope killer ^.^

[kayheem]

Also, may be we never recommend newtonian to anyone, especially when someone ask about what scope to buy... our answer nomally is refractor, SCT and MCT... but seldom see people mention newtonian. So may give an impression that newtonian is no good.

Have a nice day.

Actually, I was the one recommending the 5" MCT to newbies in Singastro. This was because the 2 main considerations were portability (they do not drive) and cost. In the US, the recommended scope for newbies is usually the 6" or 8" dob.

Maybe VinSnr, acc and the both of us should go round recommending the newt more! The slower newts have a smaller secondary and they give sharp, colour-free views.

Kay Heem

[kingkong]

...you should aim for a Newtonian larger than 8"... at least 10" and above.

like the Singaporeans say: money not enough
and dobs are apparently still not good for imaging. otherwise will be very attractive.

It may also because newtonian require collimation and collimation seem to be very difficult... at least that is what I think before I get my 6" F5 newtonian.

i'm glad to hear it may not be that difficult.
but i do expect it to take longer to setup, the st102az is definitely a pickup-walkoutside-setdown-observe scope. that's why a fixed pier is in the longer-term plan, may be to also help keep the counterweight away from the tripod legs (in fact i've never seen a goto-eq in action to know how bad a problem it's :oops: )
then will go to TG's website to get some tips on how to get going...

[Airconvent]

heh. we should have a newtonian with zambuto mirror. it will become the next scope killer ^.^

there's already one in Singastro! have you forgotten CC's Portaball?
anway, the most significant disadvantage of Newtonians are still its bulkiness which makes it very clumsy. Plus you need a good equatorial mount to make sure you images are not "disco"ing away while you focus.
and as everyone has stated : set up time . Look at cc, all that effort to set up his portaball...no wonder he always konk off at 1 am exactly for all Mersing trips!

rich

[weixing]

Hi,

anway, the most significant disadvantage of Newtonians are still its bulkiness which makes it very clumsy. Plus you need a good equatorial mount to make sure you images are not "disco"ing away while you focus.

I do agree with you that any 6" and above Newtonian are very bulky and require a very good mount. But I think any fast Newtonian (paraboloidal mirror version) smaller than 6" is very portable and may be used on a good camera tripod... like a lots of us doing with refractor. For example, the Sky-Watcher 4.5" F4.4 and 5.1" F5 newtonian are actually very portable... as portable as any type of scope of the same aperture. So I cannot find any excuse not recommend them.

Have a nice day.

[VinSnr]

Hi,

want a newtonian for my next scope.
mainly because:
1. best aperture:$$$$
2. better for dso
also because:
3. better viewing
4. i've a st102 az. can still fit an 8"SN+EQ in my car trunk
5. my usual viewing location is <50m from my storage location - hmmm... i think i still like to build a permanent observatory with fixed pier and all

so... any one taking order for lxd75 8" s-n?

Wow... envy you.. Then you should aim for a Newtonian larger than 8"... at least 10" and above.

Anyway, I think another reason that newtonian is not popular is that newtonian give a low technology feeling and also low on publicity.

There are always somebody talking about new achromatic refractor that is as good as a apochromatic refractor at a fraction of cost, the xxx brand new apochromatic refractor is better than the yyy brand apochromatic refractor, the SCT use a new coating that enhance the transmission to a 9x%, the new MCT give a view as good as an apochromatic refractor and etc.... But nobody is talking about newtonian.... since newtonian had basically unchange from the 17th century.

Also, may be we never recommend newtonian to anyone, especially when someone ask about what scope to buy... our answer nomally is refractor, SCT and MCT... but seldom see people mention newtonian. So may give an impression that newtonian is no good.

It may also because newtonian require collimation and collimation seem to be very difficult... at least that is what I think before I get my 6" F5 newtonian.

Have a nice day.

I use to have the above impression, but the great views of a reflector change it all. Let me tell you why.

In one of the Mersing trip many many years ago, I got a chance to look through a very good sample of an 8" SCT. I shall not name the owner here. The optics in his SCT is exquisite.

Not far away is another guy with a 8" reflector. I can't remember the focal ratio for his scope. I also cannot remember the owner anymore but all I can remember is that for the same object, the image at the eyepiece was brighter than the 8" SCT. It wasn't a tad brighter, it was very clear that the reflector image is cleaner with better contrast.

After that experience, I ordered the 8" Portaball. Best images ever in my life. Of course, that Zambuto mirror helps a lot, but I bet that even with a 1/8 mirror, the reflector will beat any 8" scopes in its path (short of a 8" APO that cost an arm and a leg of course)

[VinSnr]

heh. we should have a newtonian with zambuto mirror. it will become the next scope killer ^.^

there's already one in Singastro! have you forgottne CC's Portaball?
anway, the most significant disadvantage of Newtonians are still its bulkiness which makes it very clumsy. Plus you need a good equatorial mount to make sure you images are not "disco"ing away while you focus.
and as everyone has stated : set up time . Look at cc, all that effort to set up his portaball...no one he always konk off at 1 am exactly for all Mersing trips!

rich

actually, I think setting up his Portaball is far faster than setting up an EQ mount!

I know best because I owned that scope before and now I own a EQ GOTO. Sometimes when the Autostar is being notti, you really wished you have something like a dob. Imagine all this find north, leveling, find two stars and stuff, heck, the guy with a dob would have finish setting up and on his way observing the skies.

[kayheem]

like the Singaporeans say: money not enough
and dobs are apparently still not good for imaging. otherwise will be very attractive.

Not true that dobs are not good for imaging. With a tracking equatorial platform, it is possible. Take a look at:

http://astronomy-mall.com/regular/produ ... ms/pg5.htm

http://astronomy-mall.com/regular/produ ... ms/pg6.htm

Kay Heem

[MooEy]

think main reason is not many gd newts are brought in. how often do u see a killer newt with zambuto optics. waiting list for one of those stretch few months.

i wouldn't argue which design gives the best views, it seems that at the end, it depends on how well it is made. comparing celestron sct to quality newt doesn't do cassegrains any justice.

views thru mewlons are way better than typical celestrons sct, rivaling those apos. views of zambutos newts are great too. it's a matter of preference in the end. whether u like cassegrains/refractors on gems or a nice dobsonian.

~MooEy~