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nephilim

Skywatcher Quattro f/4 imaging Newtonian

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Having only recently become hooked on astronomy i've already been bitten by the imaging bug, I've just bought & i'm awaiting delivery of 'Making every photon count' but was after some opinions on the above scope (either the 8" or 10") with an EQ6 pro. Would this be a good way to start. The OTA's seem reasonably priced (I'd be looking at a 2nd hand mount) but are they any good & does anyone have any experience with either.Thanks.

Steve.

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I have seen images with the above scope, and you wont be disappointed. I have heard that they need to be collimated for pin sharp clear images ( not sure how much work though ), but thats what i have read. most beginners to astro photography like myself, tend to go towards ota's, either a doublet or triplet, myself i went for the skywatcher ed80 pro and have not looked back, but it has a f stop of 7 where as the scope you mentioned has f4 so much faster, allowing shorter exposures compared to the f7.

im sure someone that is more advanced on this will give better advise or from someone that has one

Steves book is a must and a very interesting read for astro imaging, i have had it for a while now and still keep going back to it for information and tips

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I'd have thought at f/4 collimation would be pretty critical, so you'd need to be confident about doing it. I wonder if it might not be better suited to a permanent setup where there's little chance of anything disturbing collimation between sessions. There are a few SGL users who have one or have had one to the best of my knowledge, so they should be able to give a good idea of what's required.

I'd suggest you have to ask not only "Is it a good scope for imaging?", but also "Is it a good scope for starting imaging?" The answers may not both be "yes".

James

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User Astronut on here has a f4 orion and had an absolute nightmare collimating it. So much so that at least 3 others had a try before it was finaly achieved. He can now do it fairly quickly but it was a lot to learn and he has a few diferent collimating tools to check for accuracy. I also looked at getting one but decided as I am still very much a beginer the f5 was the wiser option. Plus if I get the sw coma corrector it has a .97 reduction making the scope f4.2 (I'm probably wrong as was a while ago I read it and as this is sgl there are limitless amounts of people who like to correct everyone anyway).

HTH Rab.

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I have seen images with the above scope, and you wont be disappointed. I have heard that they need to be collimated for pin sharp clear images ( not sure how much work though ), but thats what i have read. most beginners to astro photography like myself, tend to go towards ota's, either a doublet or triplet, myself i went for the skywatcher ed80 pro and have not looked back, but it has a f stop of 7 where as the scope you mentioned has f4 so much faster, allowing shorter exposures compared to the f7.

im sure someone that is more advanced on this will give better advise or from someone that has one

Steves book is a must and a very interesting read for astro imaging, i have had it for a while now and still keep going back to it for information and tips

Great photo's for just starting out!! Altho i'm looking at a year down the line I have heard the ED80 mentioned quite alot & was wondering the type of photos achievable from it, judging by yours i'd say they are great. I'll be giving the book a good read first.Thanks. :smiley:

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I'd have thought at f/4 collimation would be pretty critical, so you'd need to be confident about doing it. I wonder if it might not be better suited to a permanent setup where there's little chance of anything disturbing collimation between sessions. There are a few SGL users who have one or have had one to the best of my knowledge, so they should be able to give a good idea of what's required.

I'd suggest you have to ask not only "Is it a good scope for imaging?", but also "Is it a good scope for starting imaging?" The answers may not both be "yes".

James

Thanks James, I understand what your saying & i think i'd be pushing it with my VERY limited knowledge ( It's the old aperture bug im afraid, thinking that if I'm going to shell out big money then i want the best i can afford) As i've posted above to ravestar, maybe it'd be best starting smaller ( I'v read good things about the ED80 pro so maybe that would be the way foreward )& then maybe up-grading. I do know that a good mount is the priority so i'd be saving for that first & hopefully gain some knowledge from Steves book. Lots of research first as I have a good year or so till i'd have saved up anyway. :smiley:

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i have just got the F4 8 inch quattro have to say i still haven't nailed the collimation i have just bought the farpoint auto collimator to aid collimation, my laser ( baader mkll) and my cheshire just dont get me there and after seeing the review on the auto collimator its a must for fast newts, but im loving the photon eating machine :grin: so if i was you get the 8 and spend the rest on a coma corrector and some collimation tools and you will not be disappointed. heres 5x4 min subs on the bubble as you can see my focus is a lil off but it shoes how fast these are

post-6284-0-50210400-1355069464_thumb.pn

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You have started in the right direction ie having a good solid mount for starters, read Steves' book "making every photon count" before any further spend.

What camera have you in mind? and will you autoguide (highly recommended), will you have an obsy to house the kit or are you going to set up each time?

If you have to set up each time I would go for an ED80 with flattener plus a Canon camera, QHY5 to make a finderguider, that would be a "relatively" cheap start, remember aperture is not critical for imaging.

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I kind of have the impression that starting with an ED80 is a bit like "doing your apprenticeship" in imaging. You get to learn loads with a (relatively) forgiving instrument and to develop your skills before moving on to other things if you decide you want to. The lure of going straight for a large aperture "photon hoover" might be strong, but a small aperture scope can do many of the same things; it might just take a little longer...

James

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You have started in the right direction ie having a good solid mount for starters, read Steves' book "making every photon count" before any further spend.

What camera have you in mind? and will you autoguide (highly recommended), will you have an obsy to house the kit or are you going to set up each time?

If you have to set up each time I would go for an ED80 with flattener plus a Canon camera, QHY5 to make a finderguider, that would be a "relatively" cheap start, remember aperture is not critical for imaging.

I honestly dont know wether to go 4 a CCD or DSLR, I'd be setting up each time as an obsey is out of my pay range haha, I'm really just trying to get as much info as possible. I'll be giving Steve's book a good going over in the nxt couple of weeks and then the saving will begin (plus no doubt, many questions. :grin: )

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Here is a very cheap way of having a "mini obsy" which at least negates the need to set up the mount.

http://stargazerslounge.com/topic/46537-what-lies-beneath/#entry889126

I upgraded to a roll off shed, note not a roll off roof! I had a 6x4 standard shed that was modded - cost £270 plus 4 rollers at £4 each, it works a treat and you can leave the scope set up as well.

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The Quatro series are great scopes but might be tricky for begginers to master due to the afforementioned collimation requirements. It's not as difficult as some people might suggest- but unlike a refractor it's not 'plug-and-play'. To get the most out the scope for imaging you'll also need to budget for collimation tools and a decent Coma Corrector. I have been advised that the steel tube versions don't like a lot of weight hanging off the foccuser as this causes uncontrollable flex in the tube around where the focuser is bolted on? I have not experienced this effect myself- but I'm only using light weight cameras.

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I have stuck with the more plug and play refractor option and I have to say that it has worked well. Steve's book is an excellent read and will really help to put it all into context. The 80ED really is a proven scope and there are many on here that use 80mm scopes. Regarding a camera, either DSLR or CCD - That is a can of worms!! Have a look at one of the field of view calculators (http://www.12dstring.me.uk/fov.htm) and you can get a feel for the field of view you will get with a scope and the 2 different camera's.

The sensitivity and versatility of the mono CCD can not be beaten, but you will also need filters and a filter wheel, which adds to the already escalating costs. A OSC (One shot colour) CCD is an alternative, similar to the DSLR you are collecting colour data in one go and they are more sensitive than the DSLR. Chip size though and price is where the DSLR wins hands down. Have a look in the imaging section and people's signatures, there's some great DSLR images out there. If the DSLR is modded then that will work even better.

It will all become clearer in Steve's book if the above sounds a bit foreign at the moment!

Just be aware as well of the time that imaging takes. The data capture itself (which can run into many hours) is only the start and processing the data to get an image out of the other end can take almost as long again. Software can be purchased and can be expensive, or there is free stuff out there (such as GIMP for processing and DSS for stacking).

Hope that helps.

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Here is a very cheap way of having a "mini obsy" which at least negates the need to set up the mount.

http://stargazerslou...th/#entry889126

I upgraded to a roll off shed, note not a roll off roof! I had a 6x4 standard shed that was modded - cost £270 plus 4 rollers at £4 each, it works a treat and you can leave the scope set up as well.

Excellent job there. :grin: Unfortunately my scope travels with me from Yorkshire where i live & the lake distrrict where my girlfriend lives ( Jet black skies) but that is definatley something to remember if the time for me 2 move up there ever comes.Thanks

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I have stuck with the more plug and play refractor option and I have to say that it has worked well. Steve's book is an excellent read and will really help to put it all into context. The 80ED really is a proven scope and there are many on here that use 80mm scopes. Regarding a camera, either DSLR or CCD - That is a can of worms!! Have a look at one of the field of view calculators (http://www.12dstring.me.uk/fov.htm) and you can get a feel for the field of view you will get with a scope and the 2 different camera's.

The sensitivity and versatility of the mono CCD can not be beaten, but you will also need filters and a filter wheel, which adds to the already escalating costs. A OSC (One shot colour) CCD is an alternative, similar to the DSLR you are collecting colour data in one go and they are more sensitive than the DSLR. Chip size though and price is where the DSLR wins hands down. Have a look in the imaging section and people's signatures, there's some great DSLR images out there. If the DSLR is modded then that will work even better.

It will all become clearer in Steve's book if the above sounds a bit foreign at the moment!

Just be aware as well of the time that imaging takes. The data capture itself (which can run into many hours) is only the start and processing the data to get an image out of the other end can take almost as long again. Software can be purchased and can be expensive, or there is free stuff out there (such as GIMP for processing and DSS for stacking).

Hope that helps.

Thanks, I'v got a great deal to learn so i'v A LOT of reading to do. I took this

Capture 12_9_2012 7_44_02 PM.bmp

with my 130m Skywatcher & X-Box combi last night & the proccessing took a long time so I do appreiciate that part of it. Steve's book should arrive tomorrow which i'm very much looking foreward to. Thanks for ur advice. :smiley:

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I started imaging with a f4.8 10" newt back in 2004, and I am still using the same scope today.

It's a steeper learning curve than say an 80ed but the principles are still the same you just have to be more accurate.

Mike.

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I started imaging with a f4.8 10" newt back in 2004, and I am still using the same scope today.

It's a steeper learning curve than say an 80ed but the principles are still the same you just have to be more accurate.

Mike.

Thats what i'd heard, iv just got Steve's 'Making every photon count', I think i'll start with the ED80 & take it from there. :smiley:
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I started imaging with a f4.8 10" newt back in 2004, and I am still using the same scope today.

It's a steeper learning curve than say an 80ed but the principles are still the same you just have to be more accurate.

Mike.

Fantastic photos Mike! I particularly like the ISS pic.icon_salut.gif

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Its a pretty sweet setup if you get the collimation right, some of the images are excellent with this mount and its very much advertised as an imaging scope. The EQ6 Pro again will give you great shots, love to see some of the images when you do get set up, sure you will have lots of fun.

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I'd agree with the thrust of this thread. Fast is good in imaging and aperture is neither here nor there, out of context. However, fast is also difficult and, if you want it to be less difficult, very expensive. This is because fast systems are intolerant of every possible optical and mechanical inaccuracy. The Quattro is admirably cheap but this means that it requires input to get it to where it might be if you bought it from ASA, Takahashi, etc and paid a fortune for it.

DS imaging is never going to be easy. How hard do you want to make it? I like refractors because they make it easier.

Just to repeat that aperture fever belongs in visual observing and not imaging, this image is a collaboration between four SGL members using refractors of 85 and 106 mm. What matters is signal. You get signal from long total exposure time and/or from fast optics. Both if possible!

http://ollypenrice.s...TEC CORE-X3.jpg

Olly

Edit: Ooops, a larger refractor contributed a tiny bit of the inner core. I'd forgotten that bit!

Edited by ollypenrice
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I'd agree with the thrust of this thread. Fast is good in imaging and aperture is neither here nor there, out of context.

Olly

Aperture, focal length and focal ratio (our F number or the 'fastness' of the system) are all inter-related, I wouldn't go so far as to say neither here nor there since one depends upon the other.

Let us consider three 'real world' imaging telescopes all of an arbitary 600mm focal length and in theory capable of producing the same image.

Top of Olly's list might be a super fast 115mm F5.2 apochromat triplet like this one:

http://www.teleskop-express.de/shop/product_info.php/info/p5174_TS-PHOTOLINE-115mm-F-5-2-Triplet-SuperApo-with-RICCARDI-Reducer.html

The light collection area of the 115mm lens is 16sq inches.

Moving down the budget scale is a 150mm F4 Newtonian (still 600mm fl):

http://www.teleskop-express.de/shop/product_info.php/info/p4762_GSO-6--Imaging-Newtonian---6--f-4---2--Monorail-focuser.html

The F4 scope has a light collection area of 27sq inches- meaning exposure times of almost half the refractor.

Moving back up the budget scale you could buy a 200mm F2.8 Boren-Simon PowerNewt:

http://www.teleskop-express.de/shop/product_info.php/info/p4611_Boren-Simon-8--f-2-8-PowerNewton-Astrograph---Carbon-Tube.html

The F2.8 scope has a light collection area of 48sq inches or in practical terms- roughly a quarter the exposure required by the fast refractor of the same focal length.

For ease of use (especially for Olly's visitors who are on holiday and thus have no real time to tinker) the fast refractor is the way forward. Anyone with enough time to play (and a suitable dark sky site (F2.8 will punish any hint of light pollution!)) might try out the 200mm/F2.8 rig. Anyone on a tight budget could use the 150mm/F4. Horses for courses really- but if you're imaging ultra faint targets or maybe using narrowband filters then the Newtonians must have some attraction?

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By way of comparison to Olly's stunning M31 image here:

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-FGgG233/0/X3/M31%20LES%20OLLY%20TOM%20TEC%20CORE-X3.jpg

this is what M31 looks like after just 10 seconds through a 300mm f2.9 (badly collimated!!) scope from my light polluted site.

DSIR5952_noels_002_.jpg

Imagine the faint signal that could be collected after a couple of hours.........

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I thnk that's fair enough. I suppose my thinking would be that you often get few good nights in the UK (and here too, at the moment!!!) and a fast scope will make the most of them provided it is ready to go. But if it ain't ready to go your clear night will be consumed by fiddling.

Very tough call.

Olly

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I thnk that's fair enough. I suppose my thinking would be that you often get few good nights in the UK (and here too, at the moment!!!) and a fast scope will make the most of them provided it is ready to go. But if it ain't ready to go your clear night will be consumed by fiddling.

Very tough call.

Olly

good advice that Olly, one of the reasons i chose the quattro not getting enough data, we get enough cloud cover to learn how to collimate them aswell :grin:

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