Aperture, light pollution & your back

[scarp15]

Grab and go binoculars such as 16x70 with monopod would be my own preferred primary home use fix, though I do use a 76mm frac and 8" dob occasionally when observing under home skies - but prefer to take them camping.  

[swamp thing]

8 hours ago, acey said:

The people who feel greatest aperture envy are often ones who live in light-polluted places and think that aperture would solve their problem, when really the answer is petrol.

 

^^  Great sentence acey. 

The humble tank of gas, the best astro accessory one can buy.  

[faulksy]

if you go big with say a dob just leave it built up and wheel it outside nothing quicker than that, or if you want everything as acey and steve say a bit of fuel and join us were going away this weekend to mag 21.7 skys this is were your jaw hurts when it hits the ground . you wont think about not going away again

[John]

A really interesting thread this with some great contributions and, perhaps unsurprisingly, varied conclusions

I do 99% of my viewing around 10 feet from our french windows on a moderately light polluted patio with trees and houses blocking some good chunks of sky.

The key things that I've found I need from a scope to ensure that it gets used given the above constraints are:

- simple to set up

- moveable around the patio / lawn to dodge the lit areas and trees

- reasonably quick cool down time because the scopes live in the dining room

I've settled on using refractors and dobsonians up to 12" in aperture and without power so no drives, goto, dew busting etc.

I've owned one 12" dob which turned out to be too heavy once set up (Meade Lightbridge) so I dropped back to a 10" Orion Optics for a while and then went for a 12" F/5.3 OO optical tube and a dob base built for me by Moonshane which has kept the overall weight of the whole 12" dob to around the same as the Skywatcher 10" dob so movable.

While the LP and other viewing issues mean that I'm not always able to fully exploit the 12" dob, I've seen a number of things with it that my other scopes simply could not show me so it's been well worth having and for the darker parts of the year will be my most used scope.

Whether my approach is right or wrong, fits a pattern or eshews one, I don't really mind. After many scopes and many years I've found what works for me in the hobby and thats the important thing

Having had some more funds for equipment available lately I've been able to consider really big apertures but they just won't work for me and I'd hate to see an 18+ inch scope gathering dust when others could put it to good use so I've resisted the lure of really large aperture despite having experienced 1st hand what that can deliver under good, dark skies 

 

[Charic]

Its  often said that Under identical conditions, using the same branded telescope and eyepiece combination, the scope with the larger aperture, will allow you to see more!

The scope with the larger objective/mirror (aperture) simply  gathers more photons, providing for a larger, brighter image, allowing you, the viewer, to observe the faint, and finer details.

Not only will the visual details increase, so too will the  price, making bigger scopes unaffordable for some folk, or the weight and size increase, reducing portability, making the scope unusable for others? 

Light pollution may cause a loss in contrast between your target and the sky, which renders some faint targets almost impossible to observe, but whatever the limits, the smaller scope will reach its limit first.

Any area of no light pollution should provide the best condition for a telescope to work its magic, finding that area is key!

I too have considered a larger scope,and from the advice gleaned from other members, and web browsing,  It would appear that I should see a marked difference using a 300P instead of my 200P, but alas, only a side-by-side test from  within my  garden would satisfy and pay testament to whether I need a bigger scope, or wan't a bigger scope? At present I have ease of access to the garden, I can lift the Skyliner in one go, its a no brainer to use, and I'm  quite happy with the results so far! except for the size of the final image, limited by the  telescope design, another reason to go bigger!

I have access  to some of the darkest UK skies, its just getting out there, that's my issue, so if its an issue now, with my 8" 200P,  surely a 12" 300P would be more of an issue, and with a smaller car since my last scope trip, am I mad? 

But if a 300P produced the goods from the garden, in essence, better than the 200P, then the upgrade would be a worthwhile investment, and what would become of the rare visits to the dark site?
They'll still be stunning/breathtaking, despite the effort required!

[N3ptune]

If I have a backyard in a low pollution area then I would consider installing a large telescope in an observatory. If I have to carry some material, it has to be light enough to prevent negative effects on my motivation.

For me, It's not worth getting a better image if I get tired at the sole idea of carrying the stuff outside. Right now EQ5 and 203 x 1000 is my absolute limit, no doubt about it.

(Maybe some folks are stronger then others)

 

[spaceboy]

5 hours ago, N3ptune said:

If I have a backyard in a low pollution area then I would consider installing a large telescope in an observatory. If I have to carry some material, it has to be light enough to prevent negative effects on my motivation.

For me, It's not worth getting a better image if I get tired at the sole idea of carrying the stuff outside. Right now EQ5 and 203 x 1000 is my absolute limit, no doubt about it.

(Maybe some folks are stronger then others)

 

This is my concern. Motivation! It's a no brained that a larger scope will weather permitting perform under dark skies over that of a smaller scope but back home with LP would the views still be the driving factor to trapse up and down a flight of stairs several times over the once or twice with a smaller scope. From some comments I fear not. Given the once or twice a year I visit dark skies (usually star parties) I'm now not sure even the gains of 2-3 nights amazing views would compensate for all the lost nights at home due to the thought of doing my back in lugging over size kit around to look at washed out skies. As others have said the best scope is the one your likely to use and this had always been my motto. A moment of madness passed over me at a rare opportunity to go big and I think my imagination went a little wild. Just nice to see that member helped me keep my feet on the ground.

[ollypenrice]

The size of a scope is only one factor defining its portability and ease of setup. The other factors are where you store it and how you move it.

When I lived in the UK I followed an idea from Phil Harrington's Star Ware book and made a simple wooden palette to which I bolted a tripod mounted Meade LX200 10 inch. I also bought a sack truck for about £50 (and which is still ferrying guests' gear to and from our observing sites fifteen years later!) The scope lived in a cupboard I made for it in our garage and I had a small concrete pad for it surrounded by flowers so it was unobtrusive. The sack truck slipped under the palette and out rolled the complete scope in one go. Two minutes would be a good estimate for setup time.

Obviously the details of any such arrangement will be house-and-garden-specific but that worked for me.

Olly

[brrttpaul]

I have a small garden facing east, and when I first started I was lugging everything about (HEQ5 mount, skywatcher 150 etc, I soon realised set up/take down was taking way to long so I installed a pier and a socket, I also swopped the 150 for an equinox ed80, I am now going about building a small obsy around it so I dont have to lug the battery in an out ( the mount works better through the battery).

[Moonshane]

Occasionally, I do consider selling my 16" dob to buy a really nice frac (maybe a Tak 100 doublet) but can never seem to make the (emotional?) break.

[niallk]

Hi, I've only ever looked through my own 2 scopes, so have very limited experience.  I've a 250px solid tube, and a 15" truss dob.  I consider the 250pv very manageable for carrying out to my back garden - two trips and done - takes 2mins: grab and go.  It's not really heavy, just a little bulky.  But: I never put it in my car...

When picking my 15", I really put a lot of emphasis on the ease of setup.  I store it fully assembled in the house, so it requires dissembly + reassembly to get it outside. It takes 4 trips (rocker box, mirror box, trusses, UTA) to setup, but I get it done in 8-9 mins.  Not bad!  Only the mirror box is heavy; I do have wheelbarrow handles, but choose to carry it.

I think it's nearly "ease of dissembly" that's the most important: when it's late, you're tired, frustrated with cloud/dew.

I've had my 15" 1.5yrs, and I've hardly used my 10".  Furthermore, I've started to put it in the car and drive 15mins to a darker site with better horizons if the conditions are good - something I've never done with the 10".

I much prefer observing with the 15": the increased aperture on all targets (planets, DSO, lunar), very importantly coupled with the beautifully smooth motions.

Where I live, I regularly see the milky way, but there is also LP/neighbour's lights I did consider larger aperture, but - besides cost - I convinced myself that I would use the 15" regularly; I was afraid an 18" would become a bit more of a 'special occasions' scope.  Of course I hanker after larger aperture, but I think 15" is a very practical size for me, and hopefully will continue to give years of pleasure.

Besides weight and size, captive components, no tools required, and ease of assembly by a single person is important. Looking up some YouTube videos of someone assembling their scopes is useful: compare say an 18" Obsession to an 18" Skywatcher Stargate...

And lastly the 'C' word.  I almost never have to collimate my 10".  It is years since I touched the secondary. I collimate the 15" every time I assemble. I use the barlowed laser method, and with knobs on both secondary and primary, it's done in ~1min.  It only ever needs a slight tweak, and isn't a chore tbh - it even boarders on fun using a laser in the dark.

[breezy]

I've fought with aperture hunger for ages,  largest scope is a sky max 127 which is fab for planets,  my garden points North,  has a railway built up on the right and suffers from light pollution.  One thing that has helped is the twenty foot tarp I put up against left hand fence,  reduces the annoying security light glare from neighbours quite a bit.  Nxt scope will hopefully be 300mm dob,  recently started using a field five mins away.  Still get glare etc but more freedom of movement 

[iPeace]

I very much appreciate the thoughts and considerations regarding this topic.

The prospect of a limited number of observing nights almost put me off acquiring a telescope in the first place... So glad I pressed on.

I do make a point of maintaining short setup time and portability - hand-held bins and small fracs are the ticket. It certainly challenges me to really hone my observing skills and I'm grateful for that.

I've never used a scope with more than 85mm of aperture. And the more I look, the more I see through my equipment. Nonetheless, the more I see, the more I want to see and the more I want to find out what difference a bit of aperture will make. So the aperture may well creep up a bit, but I will never be without a genuine grab-and-go option. (See the one emerging from his dwelling at daft-o-clock to pull a pair of binoculars out of his undergarments? That's me.)

And as for a big dob, well... in all honesty it's like a great, impractical, unlikely 'maybe' - like the huge pickup truck I'd love to drive someday, but cannot justify or prioritize by any means.

To summarize: if there's even the slightest chance it will stay indoors on a clear night, it's not my kind of scope.

[LukeSkywatcher]

On 27/07/2016 at 21:32, spaceboy said:

I know it's not possible to see the Rosetta with out a filter (or at least I wasn't able to even at a dark site) but I would have thought you could make out the veil in your 8se with out the need for a filter. Pointless in practice as a filter makes it far more apparent and more enjoyable to look at but none the less not impossible with out filtration.

Shane I can just about make it out in an 8" newt OIII at home but it was so poor it didn't hold my attention for long. I should really give it a go in the 10" come to think of it.

I'd never tried for the Veil in the 8Se without the OIII. So i cant say if i would see it or not. I just wanted to clear up any confusion.

[spaceboy]

Has to be from a dark site when viewed with out a filter so I hope I haven't created any confusion either.

[John]

I managed to see the eastern Veil segment with 15x70 binoculars and no filter on a very dark night a couple of years back. Overhead the sky here can get very dark but the horizon "glows" from Bristol and Newport impact DSO's quite noticably. The trick I've learned is to wait until my fainter targets have risen quite high before trying to view them.

 

[Piero]

Well, I went all for quality and just accept the limitations of my equipment. At this time I prefer so. In the future I hope to observe with a Dob within 8" and 12" regularly. 

To me having time to observe and sufficiently dark skies are far more important than aperture. 

[Timebandit]

On 28/07/2016 at 09:37, Moonshane said:

Occasionally, I do consider selling my 16" dob to buy a really nice frac (maybe a Tak 100 doublet) but can never seem to make the (emotional?) break.

 

I had the same problem, Dob or frac,  frac or Dob. It was getting very confusing and difficult and you do seem to latch on the your existing scope especially if it has been a great performer . 

I love the aperture of a big Dob, i loved the ability of the Dobs aperture size to find more DSO and get more detail out of them. I loved the ability of the dob to get higher magnification clarity on planets. I realised I could not do without the dob as it was a cracking scope and would regret selling it 

But I always loved the views and versatility of a frac. A frac just has that crisper more engaging viewing ability IMO. A frac on a AZ mount is also such a quick and easy get up and go or set up and go combination that it really does take some beating as non thinking non strenuous set up.

Therefore in the end I had a brain wave ?. Get both . Don't have to do away and sell your long loyal existing scope, but at the same time you can have the benefits of both viewing systems. A frac and a Dob a foot in both camps and double the benefits, so over a period of time and money availability that's what I have managed to achieve. Get two IMO great quality scopes.  

The trouble is then when you are using the Dob sometimes you think maybe that target would look better in the frac looking at you in the corner. And when your using the frac you sometime think that target would look better in the unused dob. Double the choice and then you double the problem which to use?  . But over a period of time you learn to assess the strengths and weaknesses of your scopes and therefore it gets a lot easier to decide what scope you are going to use on a particular night in particular seeing conditions at a particular location.

My advice Moonshane is keep your long existing companion  the big Dob. And when funds,   time allows  get that long time niggle of that lovely frac you have always thought about and wanted. Double  the scopes then you double your fun ?

[MARS1960]

I'm not sure this answers your questions but here's my two penneth worth.

I have an 80ED ds pro which i will be selling..............eventually, ,,,,,,,,,,,,,,,, maybe . 

Why sell a great scope unless your begging for a triplet i hear you cry.

Well, i concur but i can't warrant keeping three scopes, but i DO need two, hence the sale,,,,,,,,,, possibly maybe 

So i have just bought an astro tech 72ED  giving me a reasonably fast f6 and a nice wide view @ 430mm FL.

But i have also just bought a Ritchey Chretien 6" revelation @ f9 with a 1370mm FL. I consider the 80ED a fabulous scope, but it was a scope that for me sat in the middle. 

I think with the two new scopes i have the best of everything, but it takes at least two scopes to have that privilege. ooops, did i say "middle" and "at least two scopes", i'm keeping the 80ED too .

[DannyLee]

in 1978 I bought a ten inch mirror set from Fullerscopes, spent months building a wooden tube and a stand from screwed pipe ( dobsonian principle before it was called Dobsonian) used it once or twice, brilliant planetary views, required two people 1 hour to drag out and set up. I still have that mirror set, its in pristine condition almost 40 years later, its had maybe 10 hours use in all.

On the other hand, my 127 Mak gets used lots...

 

Regards   Dan

[Scooot]

I've only just seen this thread so thought I'd add my bit. I have 3 scopes 60mm tak, 10" Orion optics & 16" Sumerian truss. I do nearly all my observing from home which is quite light polluted, probably mag 4.5 skies. 

1) use it as often as you would like or does the thought of all the effort put you off more often than not?

I don't use it as often as I'd like but not because of the effort of putting it up. I store it in a shed, it only takes about 10 minutes, and I only move it about 10 paces. If the forecast looks reasonable for the evening I nearly always choose the 16", unless the moons about, but even then sometimes I've set it up and stopped it down to a 6" to view doubles etc. However I don't tend to use it on the spur of the moment when the other two scopes become very useful.

2) inevitably ended up getting a smaller more manageable scope ?

I bought the 10" f4.8 first which is very portable, quick to set up and gives fantastic all round views. If I only had one scope this would be it.

3) would I give up the larger scope for the smaller scope if you could easily replace the larger scope at a later date?

Difficult to answer because I would only buy the 16" as well as the 10", not instead of.

4) feel the views are significantly better between the larger and smaller scopes under LP to let the smaller scope go?

The views are noticeably better with the 16" but the fov is narrower. 

5) wait until a point where you can have both larger and smaller scopes?

Defnitely but I'd still get the 10" first if I was staring out again.

6) the money from the larger scope would come in more handy than it sat gathering dust so get / stick with a smaller scope?

7) the improvements of a larger scope are subtle under LP skies so stick with what you have?

I wouldn't get a larger scope instead of a smaller one, I view it as a complimentary nice to have. I wouldn't say the improvement is subtle, it's different, everything is bigger and brighter.

There have been many occasions since I bought the 16" when viewing prospects looked poor, and then I happen to look out and it's clear or partly clear. On these occasions I tend to put out the 10" dob or the bab tak, or grab a pair of bins. The baby tak is also very versatile, better for trying my hand at imaging and easier to take abroad. I can use it as a widefield scope or an f10 for well framed views of the moon. Or sit it on top of the 16" for a choice of views. So all the scopes have their strengths and weaknesses, but if I had to have only one it would be the OO 10" as this is a great all rounder.