'Sweet Spots' in quality gained vs $ spent in astro equipment?

[Astro_Bot]

^^ That is the most reassuring post on acquisition and use of equipment I've read in a long time. There may be hope yet.

[gregbradley]

The overriding factor is how much and how far you are interested in doing quality AP. That determines what level of quality is acceptable to you.

I think you work these systems out in reverse. What type of image do you want to produce? At what standard? What would that require? What posted images do I admire? What equipment did they use? What is my budget? Where will I image from and what are the conditions there?

If you live in suburbia then high end deep sky imaging with any setup is unlikely to yield the high end results you may want. You would need to go narrowband which has different choices of camera and filters.

The cost of good gear is coming down with many CCD manufacturers now, GSO RCs being quite good etc etc.

The sequence is 1. A good imaging location. 2. A good mount. 3. A good camera 4 a good scope.

6 inch APO is the sweet spot for refractors but they are usually expensive although I see APM offers some 6 inch APOs that are likely to be very good.

Greg.

[Amaranthus (Barry)]

Great summary Greg.

One point of pride, beyond getting the very best image, is getting the absolute most out of a given set of equipment, whatever the price point. I've ended up going mid-range for now, and so I'll reconsider my future investments after a couple of years of milking my new setup for all it is worth!

[IanW]

Honestly I don't believe in "sweet spots" for aperture as you are going to be entirely limited by the seeing at your observing site. The best most of us in Australia can hope for is a bit under an arc minute on a good night, unless you have an exceptional location such as near the AAO.

Given the seeing limitations, as long as you can reduce the Periodic Error of a mount to under 5 arc seconds you'll get a quality image. Far more important in a mount is no flexure and that means big heavy EQ mounts or well designed Alt-Az mounts and rotators.

Small apertures simply cannot capture enough photons, even using current techniques and CCD's. Compare a shot with a 100mm refractor vs a 1m Reflecting telescope and tell me which has more detail if exposures are identical and you use the same post image processing techniques.

Just my 2 cents worth. For the record I've been doing AP since the early 70s. Back then in the pre autoguider days AP was not for the faint hearted.

[Amaranthus (Barry)]

Ian, thanks. There is at least one undeniable aperture trade-off. Larger aperture (more photos) = longer focal length at the same f/stop (smaller FOV)

[tones-]

i wouldnt go as far as to say smaller aperture cant show good detail, even something as small as the tak fs-60 series will produce exceptional images.

ive always had a thing for tak scopes though so i ended up with a fs-102, add a feathertouch 10:1 and its the scope i'd never part with for both visual and imaging.

[graham.hobart (Graham stevens)]

I think it comes down to what or where your interests lie.
IF you like wide vistas then an FS 60 with a dslr is great.
If galaxies are your thing then you have to go for a longer focal length heavier scope and with that a bigger mount.
Sometimes owning a few scopes before hand makes it easier to find the ones that suit your personal interest. I know that's what happened to me- but I spent a small fortune getting there! Luckily I don't have any other hobbies!!
What ever makes you happy if it is a tasco jobby or a $10K Orion optics.
I dream of the lotto where I could kit all my new obs out with the best- just because I could afford it! I know it won't make me happier or a better person but I would enjoy it immensely!!
I personally went from a Meade on a wobbly wedge to an EQ 6 to a PMX. I never regretted spending that money on the PMX because it's been great and looks fab too. I aim to get years of service from it.
If my Wife new how much money I have spent over the years I would be in deep deep doggy dooh! But as she says, I don't go out anywhere much and she always knows where I am!!
Graham

[marc4darkskies (Marcus)]

Originally Posted by gregbradley

The overriding factor is how much and how far you are interested in doing quality AP. That determines what level of quality is acceptable to you.

I think you work these systems out in reverse. What type of image do you want to produce? At what standard? What would that require? What posted images do I admire? What equipment did they use? What is my budget? ... .

Yep, spot on Greg!

IMO there is no such thing as a sweet spot - only a "sweet spot" for your aspirations and budget in the hobby using the spend-as-much-as-you-can-afford paradigm. Spending less than you can afford is a false economy.

I've been saying for years a) your goals will dictate what you buy and b) do your research. Keep asking yourself what you want to do and achieve. Forums like this & Google will eventually inform you what you need and your bank manager (or SWMBO) will tell you what you can afford. Forget about sweet spots. There is no simple recipe because the spectrum of goals (technical and aesthetic) is so variable.

Cheers, Marcus

[IanW]

Originally Posted by Amaranthus

Ian, thanks. There is at least one undeniable aperture trade-off. Larger aperture (more photos) = longer focal length at the same f/stop (smaller FOV)

True but it really doesn't matter if you mosiac your images.

An F10 SCT can be reduced to f6.3 with commercially available focal reducers, and down to f5 or lower if you are prepared to pay a professional optical fabricator (optician) to make you a special unit.

The latest Meade ACF OTA's run f8 and though there's no Meade focal reducer as yet, the Optec unit will work and give F5. That's a good wide field of view and can resolve to the limits of atmospheric seeing while giving a larger image scale which is vital for capturing detail.

[Brian3. (Brian)]

Just a point out of "left field."
For visual astronomy I have learnt one sad fact and that is "age equals deteriorating eyesight." At this point the eyes need all the help that they can get which in turn means the best optical quality which again in turn means more money. Sad but true...
(Also a damned good excuse to "get what you want!")

[Brian3. (Brian)]

Originally Posted by Brian3.

Just a point out of "left field."
For visual astronomy I have learnt one sad fact and that is "age equals deteriorating eyesight." At this point the eyes need all the help that they can get which in turn means the best optical quality which again in turn means more money. Sad but true...
(Also a damned good excuse to "get what you want!")

[brian nordstrom (As avatar)]

I find my 127mm f8 Istar on its HEQ5 to be 'Just Right' in quality , performance and price .
Oh yes , my TV eyepieces help .

Brian.

[Paul Haese]

LOL, how much money do you really want to spend and how persistent will you be to obtain your goals.

The later for instance can mean you get great results with modest equipment but using everything at your disposal. Peter.M is a good example. He has very modest equipment but is doing unattended all night imaging with Sequence Generator Pro and associated software and his results are very good. He gets lots of data from doing this and that makes processing easier and produces of clean images that he is very happy with.

If on the other hand you have lots of money to work with you can spend as much as you like. Though you still need to know how to set everything up, problem solve and process data. All this takes time.

The cheapest things in my RC12 dome is in fact the telescope. It has had issues and I am working through them but I am producing pretty reasonable results. However, having a good camera, focusor, dome, software for acquisition and good mount make a huge difference.

There is no sweet spot, there is just how much you really want something to fulfil your goals. You can work hard with a small budget and you can work hard with a large budget. Persistence pays off.

[cometcatcher (Kevin)]

Everyone has made very good points. One major point Paul mentions is the all important "good data". You can do much with low budget modest equipment if you have good data. That usually means shooting near the meridian away from the smogosphere and collecting as much good data as possible with a cool as possible camera.

And live on a mountain.