Thoughts Please New Scope

TrevorW · #1 27-03-2009, 11:47 AM

With the dollar being like it is and apparently staying that way for some time I was considering buying a 8 or 10 " f4 or f5 Newt for astro imaging

Please best brand and what configuration and best price

Any thoughts

Thanks

Starkler (Geoff) · #2 27-03-2009, 11:58 AM

The Vixen R200SS seems well regarded. 8" f4

TJD (Trevor) · #3 27-03-2009, 06:14 PM

are you willing to buy it off the internet

or a shop

TrevorW · #4 27-03-2009, 07:44 PM

Preferably from a shop in OZ. I have warranty issues but throw in suggestions from elsewhere

Cheers

gbeal · #5 27-03-2009, 08:06 PM

While I concur, the Vixen 8" F4 is a very good scope, what are you imaging with now, as this makes the decision easier.
Gary

AlexN · #6 27-03-2009, 08:51 PM

Yeah, I tend to agree, the Vixen is a nice imaging scope... There are plenty of examples on the net showing what the scope is capable of.. Price wise, yes its more expensive than an 8 or 10" GSO/Skywatcher Newtonian, but you get what you pay for...

chris lewis · #7 28-03-2009, 07:17 AM

Some info on the GSO 8in. /F4 below - there is a link to a comparison with the Vixen RS200.

I have had 2x GSO 8 in. F/4. Newts. Good quality for the price - only did basic AP so can't really comment otherwise. Collimation had to be exact as expected. Vixen quality is a step up.

http://www.cloudynights.com/item.php?item_id=1677

http://www.cloudynights.com/item.php?item_id=648

TJD (Trevor) · #8 28-03-2009, 11:26 AM

orion xx12 inteli scope (12 dob computerized)

dont for get 20% off york optical for iceinspace members only on the internet but

gregbradley · #9 28-03-2009, 11:28 AM

I had a Vixen R200S for a while.

A quick review for you. I was fairly new to astroimaging and was using a modified DSLR. I had had a Meade LX90 and an Orion ED80.

The Vixen was put on a Vixen Sphinx mount (a crappy mount despite being expensive).

Firstly, quality. I would not describe Vixen as high quality but more a mass producer of reasonable quality at a more affordable price. The focuser was
poor (it had a screw fitting to attach the DSLR which when screwed on ended up at whatever orientation the threads dictated so the camera would be at an odd angle obviously unsatisfactory for framing the image).

The focuser had cheap ugly plastic knobs. The mirror collimation screws were push/pull and it was extremely hard to collimate. I got an Antares laser for collimation and that made it simpler. Trying to do it without that was mission impossible. That's not Vixen's fault as any fast newt will be hard. The rule being the faster the scope the harder the collimation.

It has an extremely wide field of view so unless you are planning to use a tiny chipped camera it is really a very wide field setup with a DSLR. So be aware of that.

Other than that the mirrors seemed fine (newtonian mirrors are easy to make and this means they can be made to a high accuracy more easily than other types).

If I had one again I would;

1. chuck the crappy Vixen focuser (the plastic knobs were "Tasco-like".)
I believe a nice Moonlite focuser will fit.
2. I would use the Baader MPCC corrector as I have seen that works well. The Vixen one as I recall is designed to fit in their focuser so it may not fit other setups. Not sure about the quality of the Vixen corrector - it was OK from memory although I think it still left a bit of coma at the corners - can't say for sure though).

So the Vixen is not a scope that works right out of the box either.

The finder scope had a nice feature with the adjustment screws being spring loaded which meant it was really easy to adjust it.

My overall opinion of Vixen after using 2 of their products and their attitude towards their market and their practices is quite low. For example the Sphinx was a bugged mount which they started selling without autoguiding ability and they took over a year to release the autoguiding feature and when they did they wanted more money for it. It also did not work well.
The mount needed modification to work properly and the Starbook is very hard to use and not user friendly and is super bright at night. Basically a bug atttractor in summer.

Have you considered making your own Newt? There are lots of suppliers for this type of scope and you could put together an awesome system with known quality for possibly similar money??

I'd also consider F5 as I have a few instruments that do F5 and I think its a great F ratio for astroimaging. Fast yet not overly fussy for collimation etc.

F4 requires a lot of things to be made well - mirror holder,focuser, tube strength, even tube expansion whilst imaging with a temperature drop.
I doubt the Vixen has this nor the GSO.

Greg.

TrevorW · #10 28-03-2009, 08:16 PM

Skywatcher do an 8" f/5 and I was thinking of getting a Baader MPCC Coma corrector as well

Tandum (Robin) · #11 29-03-2009, 04:05 AM

Trevor,
I see you are imaging more and more galaxies. I'd suggest you get a scope that can see them better than a low F newt.

gregbradley · #12 29-03-2009, 08:05 AM

I suggest when you are working out what type of scope/camera combo you want to use that you start with this free calculator:

http://www.newastro.com/book_new/camera_app.php

You can see in an instant the resultant images such a system will take.
If you are interested in taking galaxies then you need long focal length and/or small chipped camera.

If you are using a DSLR then that is a fairly large chip so it tends to be a bit widefield and so would need even longer focal length to capture a galaxy.

My Tak BRC250 and Apogee U16M would not make a good galaxy setup as the image of the galaxy on such a large chipped camera would be too small despite 17 megapixel.

This is why I got the much smaller chipped 8300 camera.

Fast imaging speeds (F6 or lower) and galaxies do not mix. If you want F5 for galaxies you'll need about a 16 inch or bigger scope. F ratio is focal length divided by aperture. So to get the focal length long enough for galaxies (1800mm or so minimum) then 1800 divided by 5 = 360mm = 14 inches. There is the dilema. Hence aperture fever. Also galaxies need probably 8 inches of aperture in a reflector system to be capture easily.
My Tak BRC250 (10 inches) I consider to be at the low end of aperture for galaxies and if I wanted to specialise in galaxies I'd get something bigger.
Meade made a 16 inch Newt. Maybe one of those 2nd hand? Of course then you need a mount to handle something that large and it all starts getting expensive very fast. There's no easy work around.
One solution I see working is a very small chipped camera on about 1300mm of focal length. Mike Clemens is taking some quite nice galaxy images using an Sbig ST237 ( a tiny chip and very inexpensive - not top of the line images but surprisingly good for such an unremarkable camera).

You could barlow an F5 Newt but then you would be at F10 and lose your fast speed. But then you'd still have a nice scope for wider field imaging.

1200mm focal length is a very versatile and useful focal length as a guide and you can capture most objects with that. To get F5 though it needs to be 10 inches aperture.

So all roads lead to increased aperture over time in this hobby eh?

Greg.

TrevorW · #13 29-03-2009, 11:14 AM

That was my other option I was thinking 10" F/5 but it's whether my modest budget can stretch that far.

I've taken only a few galaxies so far as I like their structure and the thought of capturing them however I've not resigned myself to specialising and would prefer to have a good all round scope.

The brighter targets can be imaged quite well with the 80ED

Cheers

marki · #14 29-03-2009, 11:21 AM

Trevor, gerry gibbs camera house in Perth seems to be selling SW newts at the lowest prices in oz at the moment. Check them out.

Mark

TJD (Trevor) · #15 29-03-2009, 11:17 PM

i might check out gerry gibbs cammera house i heard they sell lots of different types of scopes

ps:perth doesnt have that many telescope shops does it dont forget york optical 20%off

leinad (Dan) · #16 02-04-2009, 02:21 AM

I'm going to bump this thread, and ask of the performance of the Vixen VC200L, and any other scope of better or equal performance for visual and photography at roughly same price range.

I know Trevor has similar equipment to me(EQ6Pro, 350D), so probably beneficial for you too Trev, as your looking at new scope options also.

I currently have a 8" Skywatcher dob tube used as imaging/visual OTA. I read that the VC200L with same aperture, but longer FL outperforms this and is a top performer. Downfall being focuser, and accessories, spider vane?

Anyone like to add their views on the VC200L or similar performing scope
, + price range to go with the equipment mentioned.

TrevorW · #17 02-04-2009, 02:42 PM

With the $$AU diving my budget won't go too $2500 for an 8" RC or Vixen SC, I've basically decided on this configuration

Skywatcher BD 8" or 10" f/5 Newt with low profile 10:1 crayford focuser and a Baader MPCC lens.

will come is around $1100 for the 10"

the only reason I'm going for the BD over the standard blue tube is the colour because my 80ED is black

I believe this would be a good imaging setup I could save $200 by going for the 8" but I think the 10" would be better

Tandum (Robin) · #18 02-04-2009, 03:20 PM

There's a VC200L in the 4sale forum.

http://www.iceinspace.com.au/forum/s...ad.php?t=43209

Tandum (Robin) · #19 02-04-2009, 03:23 PM

Quote:

Originally Posted by leinad

I'm going to bump this thread, and ask of the performance of the Vixen VC200L, and any other scope of better or equal performance for visual and photography at roughly same price range.

I know Trevor has similar equipment to me(EQ6Pro, 350D), so probably beneficial for you too Trev, as your looking at new scope options also.

I currently have a 8" Skywatcher dob tube used as imaging/visual OTA. I read that the VC200L with same aperture, but longer FL outperforms this and is a top performer. Downfall being focuser, and accessories, spider vane?

Anyone like to add their views on the VC200L or similar performing scope
, + price range to go with the equipment mentioned.

I moved from an 8" dob to a vixen. The Vixen is a lot lighter and shorter and easier to handle. It has an 1800mm F/L or 1250mm with the focal reducer. The focuser is fine, mine has a 10:1 knob on it. The fittings are a little odd though. It has a M62 female on the end of the tube and you need a few different fittings to get different accesories on to it with and without the focal reducer.

leinad (Dan) · #20 02-04-2009, 03:25 PM

Quote:

Originally Posted by TrevorW

With the $$AU diving my budget won't go too $2500 for an 8" RC or Vixen SC, I've basically decided on this configuration

Skywatcher BD 8" or 10" f/5 Newt with low profile 10:1 crayford focuser and a Baader MPCC lens.

will come is around $1100 for the 10"

the only reason I'm going for the BD over the standard blue tube is the colour because my 80ED is black

I believe this would be a good imaging setup I could save $200 by going for the 8" but I think the 10" would be better

Youll need to consider possible another focuser for the tube Trev. Ive heard people say that the new focusers dont allow enough travel for focus with DSLR's.