All you need is 6 inches

[Littleguy80]

A female colleague stopped me at work this week after I posted a picture of Saturn that I'd taken. After saying how impressed she was with the photo, she asked me if I had "a big, professional telescope?". "Nah, it's just 5 inches" was my reply. She looked disappointed and a bit sad for me. The conversation soon died down and I was left to regret not going with "yeah, it's a 1-30!" This left my thinking about a line I'd recently read in an astronomy book:

"but the truth is that few people could exhaust the potential of even a 6" telescope in a lifetime of observing"

So for all you big dob owners out there, how much do you think you would have missed out on if you'd been restricted to a 6" scope?

[Moonshane]

The main thing I think would be really resolved globular clusters. Everything else pretty much could be seen if I went to darker skies. Aperture does help but not as much as darker skies.

[Littleguy80]

23 minutes ago, Moonshane said:

Aperture does help but not as much as darker skies.

Interesting. Do you think the larger apertures are really just compensating for the poor quality skies that most back garden astronomers observe under? So a 10/12" dob in poor conditions is the equivalent of 6" under proper dark skies?

[Moonshane]

Maybe but even with my 16'' dob, galaxies are rarely more than fuzzy whiffs at home. At dark sites they take on more structure etc. Globs are OK anywhere with aperture. If I could swap my big scope and house for a house in a darker area with a small scope then I'd take the latter every time.

[jetstream]

42 minutes ago, Littleguy80 said:

how much do you think you would have missed out on if you'd been restricted to a 6" scope?

Piles.

[JG777]

35 minutes ago, jetstream said:

Piles.

There is medication for that, but a proper cure would be a larger scope...

[Piero]

To me, aperture and dark skies are very important in this hobby. These play as light collectors. On the other hand, optical quality plays as light refinement. 

Said this, the most important thing is the way one approaches this hobby. To me, it's about enjoying what we have, having fun, a way to relax while observing and feeling part of the big picture which originated us and will continue to exist after us. Most people ignore what there is out there in the night because they are busy with their careers, families, and lives in general. We are aware of this world beyond our little and local existence.

I don't think your colleague was disappointed because of the 5" aperture itself, but rather by the way you described your telescope ("Nah, it's just 5 inches"). I suppose your colleague really appreciated your picture and was possibly just a bit shy to ask you whether she could observe through your telescope with you.. 

[Alien 13]

I still stick with Sir PM when he used to say a 6 inch reflector a 3 inch frac or 7 x 50 binos, I cannot understand why you need more.

Alan

[jetstream]

1 hour ago, Moonshane said:

Maybe but even with my 16'' dob, galaxies are rarely more than fuzzy whiffs at home. At dark sites they take on more structure etc. Globs are OK anywhere with aperture. If I could swap my big scope and house for a house in a darker area with a small scope then I'd take the latter every time.

I'm sure glad you enlightened me with respect to dobs a few years ago Shane, what a difference it made. VG point about the globs- from my light polluted town yard the 90mm gave a faint haze for M13 for instance whereas the 10" f4.7 dob really opened it up and much more again in dark skies. Up to a certain point I think that aperture helps in light polluted skies but my reference is 19 mag so maybe in worse conditions it doesn't help as much.

To the OP- increasing aperture will increase the fine detail seen on solar system objects espc the moon, even at low mag. The view through the 15"/binos on the lunar terminator is so much better than my 10" that it hardly gets used... this is not to say smaller aperture doesn't give great sharp views, they can and do.

Actually tonight I'm going out with a Heritage 130 that gives shockingly good views- I will dial in the eyepieces for Saturn and then go observe all those great nebs out there.

If I lived in a city I would own the biggest scope I could easily take to dark skies -and observe lunar/planetary/clusters from the city. Just my thoughts.

[niallk]

1 hour ago, Piero said:

To me, it's about enjoying what we have, having fun, a way to relax while observing and feeling part of the big picture which originated us and will continue to exist after us. Most people ignore what there is out there in the night because they are busy with their careers, families, and lives in general. We are aware of this world beyond our little and local existence.

Just getting out and simply looking upwards is the main thing - whatever you have to use. In all sincerity, naked eye - no scope - is mind blowing from a really really dark site in late August when the milky way is high in the sky...

I've 2 scopes: a 10" and a 15". The 10" was my first scope and has shown me just so, so much from my back garden.  Best money spent hands down.  I can't comment on a 6".

I use the 15" >90% of the time now though being honest - for the better views on all objects - solar system + DSOs.  Globs really respond to the aperture increase as already mentioned above - I think the comparison on the Obsession website blurb underplays it for my scopes.  Nebs are brighter for the same image scale, allowing colour to be detected better. I get more light to my eye when using an O-III filter at the same image scale.  It's a more portable design and I bring it to darker locations - it's worth the effort for the views.

To the OP, did your colleague appreciate aperture, not physical length?!  I mentioned my 15" scope to someone, and they thought it was something small the length of my forearm: not something taller than me that could swallow me whole volume-wise!!!

[nightfisher]

I've  had bigger scopes but i have settle for a 5 inch Maksutov as my main scope, this is quick and easy to set up and will show me what i want to see in comfort and will take superb Luna images, i have this on a goto so i can track down the outer planets, some thing that has all but eluded me in the past, now just need some good weather 

[ronin]

7 hours ago, Littleguy80 said:

"but the truth is that few people could exhaust the potential of even a 6" telescope in a lifetime of observing"

So for all you big dob owners out there, how much do you think you would have missed out on if you'd been restricted to a 6" scope?

Very true I suspect about a 6" scope, there is a lot of possibilities out there. Equally how many people count double stars ? Will also ask how many open clusters do you want to see?  Most will pick out say 10, not many get to say 1000. A few that are listed even in the Messier catalogue are falling into the area of "Is that a cluster or not?". Messier did not catalogue objects, he catalogued "extented" items that could be mistaken initially for a comet.

Another area is the quality of the optics, will a nice OOUK 6" mirror deliver more detail then a mass produced Skywatcher 8" mirror. Almost double the light gather but how good is the image. I suspect on a few objects the 6" would win. Mainly because of the way the eye operates, this I think is the reason why an 8" mirror is compared to a 6" refractor.

Hove you completed the Messier Marathon? They say that Messiers scope was equalent to a 4" scope these days. So a 6" should pick out a lot more.

But a dark sky is really important. One person did an image of M31 (I think) from home. Then repeated the exact same exposure setting from a dark sky reserve. The difference was massive. Mind you it can work against you - go out tonight and if clear go find Cassiopeia (easy I hear you say) then go to a DARK sky, one where you are afraid to put one foot in front of the other in case you fall over the edge of the earth. Then look for Cassiopeia. Bet you cannot find it.

By the way the reply should have been "I'm good, 5 inchesis all I need."

[Littleguy80]

Fab responses. When I first joined SGL and saw all the scopes listed in people's signatures, I was gripped by aperture fever. These days I have settled down and am more obsessed with the forecast, looking for the next night with clear skies. 

With regards to my colleague, she did go on to ask about a telescope for her husband who is obsessed with space. I sent her links to articles on getting started and invited them both round to try my telescope

[Tim]

A large dob, in a dark sky, will offer you views of nebulae and galaxies which are unrivalled in any other telescope.

Fainter Hb targets like the Horsehead become a doable option as well.

[estwing]

If you're happy with 6" fine, but I'm not. The kinda stuff I'm after a big aperture is needed, which unfortunate for me!

[estwing]

A good read..

[Littleguy80]

8 minutes ago, estwing said:

 

If you're happy with 6" fine, but I'm not. The kinda stuff I'm after a big aperture is needed, which unfortunate for me

 

Nothing wrong with that  If you were left with just a 6" scope, what do you think you'd miss the most?

[Pig]

Guys I love refractors but in all honesty the views I have been lucky enough to see by courtesy of the Dob mob are in a very different league .... and under the same sky conditions I must add..... no comparison in my humble opinion, quite literally outstanding ?

[estwing]

NGC's that look like Messiers, PGC, UGC PAL and other distant targets 

[Moonshane]

The main thing is that you maximise whatever scope you have. My most used scope currently is my 120ED. It's superb at white light solar and also a great all rounder from my pretty light polluted garden. When I am at a dark site though I definitely make the most of it with bigger aperture (16") but I do always take the 120ED or my 102mm ED for the wider fields etc. I am firmly of the opinion that aperture matters but only to a point and dark skies are more important. If you have both or can access both on a regular basis then you are certainly lucky. Appreciating the bigger aperture when it's used is why despite using my 16" only a few times a year these days, I could never sell it unless I was in a real financial mess.

[Mr niall]

10 hours ago, Littleguy80 said:

 "Nah, it's just 5 inches" was my reply. She looked disappointed and a bit sad for me. 

That seems a bit harsh, but I'm sure your scope has a lovely personality!  

[Mr niall]

What did the pic look like btw?

[scarp15]

A 5" - 6" aperture is valid whatever your circumstance and from home I still like to observe many of the targets in Turn Left at Orion. Perhaps as you adapt and evolve your observing habits, you may evaluate the best suited scope for your intended purpose. For myself I started out attending a twice yearly starcamp and much of my observing was from my back yard in which my vintage C8 was quick and familiar to set up. I then started to take it to dark sky places (other than the organised Kielder starcamp) and subsequently joined a regional astro society to attend their dark site meets. The yearning for more aperture after various configurations has led to my current set up in which my 14" solid tube OOUK dob gets used a little more than anything else. This is simply because I like to independently travel to places, set up and tear down quickly, whilst delivering good aperture. Had I planned on staying over places to wild camp, a larger truss might be more applicable. Having options is always useful and smaller scopes can benefit certain targets such as some larger diffuse nebulae.   

[Scott]

I'm mainly an imager as my home skies don't really lend themselves to visual apart from some of the easier nebulae and with only an 8" newt, globes don't really jump out at me. That being said, most of my greatest experiences with astronomy have been the result of visual work and looking through various friends huge dobs at star parties account for a lot of those experiences. 
I guess if I'm honest, if it wasn't for big dobs then I'd be completely (or very nearly) missing out on visual astronomy. Or maybe it'd be just planetary/lunar from my garden whilst the camera does it's thing .
Please understand, I'm not complaining. I know many people who have skies MUCH worse than mine who still manage to enjoy their astronomy. All in all, I'm happy with my lot. Now about them damn clouds

 

[estwing]

2 hours ago, Pig said:

Guys I love refractors but in all honesty the views I have been lucky enough to see by courtesy of the Dob mob are in a very different league .... and under the same sky conditions I must add..... no comparison in my humble opinion, quite literally outstanding ?

And lets hope you get a few more...great observing with you buddy