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Skywatcher Quattro f/4 imaging Newtonian


nephilim

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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:

Wise. And that's what I am doing. And a million others. And all for the same reason: the learning curve s steep - though great fun - and there are a lot of different parts to master.

You want the scope to just "work" without constantly fiddling with collimation like you will be doing with a F4. You'll will need to master stuff like focusing for instance. Sounds simple but its more subtle than you might think. At least with an ED80 you know the scope is OK and if images look a little blurry then its not an issue with collimation. With an F4 as a newbie you'd be lost as to what the issue was - or at the very least it would delay your progress. Steve in his book states a couple of times the importance of getting some early successes.

Rgds, Steve

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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!

Thanks Olly, that photo is possibly one of the very best i've ever seen!! I'v read most of Steve's book now & the idea of starting off with a fast newt seems very naive now, I didnt realise that a small refractor is going to give me some great images & give me time to practise n hone any skills I pick up. I think if I started with the newt i'd probably become very confused & frustrated & end up selling all the gear, so i'm going to go for the more acheivable option of an ED80 on an EQ6 syntrek & take it from there. Thanks for the advice.
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Wise. And that's what I am doing. And a million others. And all for the same reason: the learning curve s steep - though great fun - and there are a lot of different parts to master.

You want the scope to just "work" without constantly fiddling with collimation like you will be doing with a F4. You'll will need to master stuff like focusing for instance. Sounds simple but its more subtle than you might think. At least with an ED80 you know the scope is OK and if images look a little blurry then its not an issue with collimation. With an F4 as a newbie you'd be lost as to what the issue was - or at the very least it would delay your progress. Steve in his book states a couple of times the importance of getting some early successes.

Rgds, Steve

As a total novice to this I just thought that the bigger the better haha, I now realise that isnt the case at all & i'm starting small with the ED80. Thanks for the advice. :laugh:
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Don't take my advice Nephilim - I am a noob at this game; take the experts advice. People like Steve Richards recommend an ED80 to start with many folk on here - me included. And if Steve says that's a good idea, then its a good idea...

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As a total novice to this I just thought that the bigger the better haha, I now realise that isnt the case at all & i'm starting small with the ED80. Thanks for the advice. :laugh:

Technically bigger is better- but the difficulties are such that that you would most probably give up in frustration before getting a decent image. Starting small with a fuss free instrument seems to be the advice.

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I have to agree with the guys above, I'v been imaging a couple of years now using a 250pds newt @ f5 and a C11 @ f10/6.3 in which i'd like to think of with relative success. So I thought it was time to treat myself to a new 8inch quattro. I promtly collimated the quattro with a cheshire the same as I do for my 250pds newt. I then had the chance of first light with a atik 314l+ on board, well I must say I was so disappointed with my results. the stars were all egg shape the diffraction spikes were off center and I even thought the mirror was showing signs of astigmatism. now this is where i agree with Olly as I wasted the majority of that night tweeking the primary to no avail, obviously it was the secondry that was miles out. Back to the drawing board as they say, I recollimated the quattro taking a little more thought and care this time. Then the second light was a massive improvement for me, what i thought was astigmatism had gone the diffraction spikes looked on center and the stars were nearly almost round I say almost as I think the mirror maybe slightly pinched, i'll investigate this before third light. what i have learned so far is that the tolerances on the quattro is critical, you only have to breath on the focuser for fine adjustment, I know this scope is going to be a real cracker once i'v mastered the collimation. I was Taking just 180 second exposures on M81in my artemis software and it was showing 31357ADU's now that is fast for what i'm use to. Tims criteria for the quattro is Spot On. IMHO the quattro is not for begginers. @ Kirkster501& Nephilim thats a great choice with the Ed80 I love mine that much I have now bought two. These scopes have to be the best bang per buck you can buy as our friends across the pond say!

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I have to agree with the guys above, I'v been imaging a couple of years now using a 250pds newt @ f5 and a C11 @ f10/6.3 in which i'd like to think of with relative success. So I thought it was time to treat myself to a new 8inch quattro. I promtly collimated the quattro with a cheshire the same as I do for my 250pds newt. I then had the chance of first light with a atik 314l+ on board, well I must say I was so disappointed with my results. the stars were all egg shape the diffraction spikes were off center and I even thought the mirror was showing signs of astigmatism. now this is where i agree with Olly as I wasted the majority of that night tweeking the primary to no avail, obviously it was the secondry that was miles out. Back to the drawing board as they say, I recollimated the quattro taking a little more thought and care this time. Then the second light was a massive improvement for me, what i thought was astigmatism had gone the diffraction spikes looked on center and the stars were nearly almost round I say almost as I think the mirror maybe slightly pinched, i'll investigate this before third light. what i have learned so far is that the tolerances on the quattro is critical, you only have to breath on the focuser for fine adjustment, I know this scope is going to be a real cracker once i'v mastered the collimation. I was Taking just 180 second exposures on M81in my artemis software and it was showing 31357ADU's now that is fast for what i'm use to. Tims criteria for the quattro is Spot On. IMHO the quattro is not for begginers. @ Kirkster501& Nephilim thats a great choice with the Ed80 I love mine that much I have now bought two. These scopes have to be the best bang per buck you can buy as our friends across the pond say!

Have you considered using or making an 'artificial star'

http://www.telescopes.com/telescope-accessories/collimation-tools/astrozapartificialstarforcollimation.cfm

to collimate your scopes in daylight? You don't want wast imaging time making major adjustments.

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I want to make an artificial star. Collimating against a real star is too much of a pain unless the seeing is near-perfect.

James

That sounds like a great idea. It would be great being able to do s star test indoors and not faff about waiting for a clear night ;)

On topic, I'd just like to add my tuppence to the preceding respondents. I started imaging with a 200p. It was fraught with difficulty and complexities. About a year later I bought an ED80 and couldn't believe the difference. Compared to my experience with the newt, imaging with the ED80 was almost plug and play, almost no faffing about. Just set it up, focus, and start collecting photons. A real joy, wonderful :)

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Have you considered using or making an 'artificial star'

http://www.telescope...collimation.cfm

to collimate your scopes in daylight? You don't want wast imaging time making major adjustments.

Funny you should mention an artificial star for collimation, I was just discussing one of these with a friend of mine Only yesterday. Its something to seriously consider. thanks for the link!
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I've been following this thread with interest, as I'm currently looking into/saving towards a 'scope and had shortlisted the quattro. Having read all of the comments I think it'd be a bit much for a beginner setup, I don't want to put myself off through frustrations, and also want something I can use for observing without too much hassle. I've removed it from the shortlist leaving either an ED80 or 150PDS mounted on an HEQ5.

Great thread.

~Kb

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As a big fan of fast newts for imaging, I thought I should point out another pro for going for a big newt compared to a small refactor like the 80ed( which I also own).

A large newt is a great all-rounder and remember you will only be new to imaging for a small part of the time you will have your scope ( mine is still my scope of choice 8 years later).

I Use my 10" f4 newt for dso, planetary, Luna and solar imaging.

An 80Ed is great for larger targets like nebular and larger galaxies but most galaxies are better suited to the higher resolution a large newt brings to the table.

The images below were all taken with my 10" newt, using my DMK21 CCD to take the planetary,solar and Luna images and also as the guide cam for my dso images.

The 80Ed will defiantly be an easier start but the newt may serve you better in the long run.

Just some food for thought.

Mike.

The moon

moon%20mosiacx58-01-12-12.jpg

M33 ( a large galaxy up close)

m33-2012-LRGB5.jpg

post-730-0-93278400-1356173508_thumb.jpg

post-730-0-29598800-1356174094_thumb.jpg

post-730-0-39055500-1356174352_thumb.jpg

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Arrgghhhh........Just when I thought I'd finaly made my mind up, MikeD comes along with images like THESE!!! haha Seriously tho I do think my patience would be sorely tested with a fast newt, think i'll stick with the ED80 & upgraded when i feel confident enough. BTW great images Mike. :laugh:

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I don't mean to give the impression that imaging with a fast newt cannot be done, I do it, many others do it, and Mike does it very well. If you already have a lot of experience with newts, then collimating an F4 Quattro is not likely to faze you. On the other hand, if you are completely new to the game a scope like an ED80 definitely makes for an easier start, as Mike says.

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I've only been 'with' my first scope (Skywatcher 130m) and have no experience when it comes to collimation, which is why i need a lot more practise, an ED80 has been recommended by most people & as I'd like a small refractor for widefield views anyway it'd make sense to get the ED as it'd fill both my needs.

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As a big fan of fast newts for imaging, I thought I should point out another pro for going for a big newt compared to a small refactor like the 80ed( which I also own).

A large newt is a great all-rounder and remember you will only be new to imaging for a small part of the time you will have your scope ( mine is still my scope of choice 8 years later).

I Use my 10" f4 newt for dso, planetary, Luna and solar imaging.

An 80Ed is great for larger targets like nebular and larger galaxies but most galaxies are better suited to the higher resolution a large newt brings to the table.

The images below were all taken with my 10" newt, using my DMK21 CCD to take the planetary,solar and Luna images and also as the guide cam for my dso images.

The 80Ed will defiantly be an easier start but the newt may serve you better in the long run.

Just some food for thought.

Mike.

The moon

moon%20mosiacx58-01-12-12.jpg

M33 ( a large galaxy up close)

m33-2012-LRGB5.jpg

Not been mentioned in this thread so far - but the other thing that greater aperture gives is more resolution, i.e. the ability to see finer details. Whilst the ED80 is a great starter scope, the experienced imager would appreciate more the resolving power of the 8".

Great pics by the way. Is the moon shot a composite?

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Not been mentioned in this thread so far - but the other thing that greater aperture gives is more resolution, i.e. the ability to see finer details. Whilst the ED80 is a great starter scope, the experienced imager would appreciate more the resolving power of the 8".

Yes it has. :wink:

An 80Ed is great for larger targets like nebular and larger galaxies but most galaxies are better suited to the higher resolution a large newt brings to the table.

Is the moon shot a composite?

yes it is but I don't want to hijack this thread so here is a link to the details .

Mike.

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In theory the resolving power does go up with aperture, this is true. My experience of the reality, though, is that effect can be a less dramatic than you'd expect. Posting up an image for a back-to-back with one of Mike's staggering galaxy shots is a bit daunting but this is M33 from a 140mm refractor.

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/22435624_WLMPTM#!i=1793652078&k=Ssgv49C&lb=1&s=O

Although I image with scopes from 85mm to 0.35 metres (that one's not mine!) my favourite remains the 85mm refractor, but it's a good one.

However, Mike shows what can be done wilth relatively inexpensive kit when you are very expert and have it all tuned to perfection. Nobody posts better images on SGL, that is self evident.

Artificial stars? Easy and cheap.

1) Our regular guest and friend Ralf Ottow, an optical engineer of some genius, simply points a scope at a tiny gap in distant trees where sunlight is coming through and uses that as his point source. However, he can also collimate a New just by looking down the front and the empty focuser with no further tools of any kind, so maybe try this method for simplicity;

2) Glue a small ballbearing to a black card and illuminate it either by sunlight or a bright torch placed near the ball. Get well away from it with your scope (houses are usually too small so I used a friend's warehouse) and you'll get a perfect point source.

Olly

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  • 6 months later...

While waiting for my copy of "making every photon count" I've been reading this and other posts with interest, I have mainly been a visual observer but have was bitten by the AP bug about a year ago when I found out just out much more of M42 I could see with a 20s digital exposure, in short AP brings out details that my eye can't, even with 12" of aperture. I have tried the camera on the 12" at various exposures, done some stacking and have learned how to use a Bahtinov mask but the issue here is that my set-up is very much at the limit of the NEQ6 visual capacity as is, adding 3 -4 kg of guide scope (or more) is probably an exercise in futility so I will admit I am giving the Altair f4 and Skywatcher Quattros serious consideration.

I appreciate the refractor arguments but at the same time Newts are something I know and love and the visual observer in me is screaming BIG APERTURE, BIG APERTURE!. I really can't see how collimating an f4 Newt can be so scary my 12" is f4.9 and has issues with the weight of the mirror cell at times (must get bigger springs). So is it really that difficult and scary using a Quattro if you have a few years experience with a newt under your belt especially if you have dabbled in imaging already?

It also occurs that I'm going to have to buy an 80mm (ish) refractor as a guide scope anyway, so even if it's a lower end frac like a Star travel can't I cut my teeth on this (I do know the optics are no match for an ED80).

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I think you should go for a NEQ6 Mount, ED80 Pro, Canon 1100D, now my reasoning for this, the NEQ6 will when aligned stick a DSO right in the middle of the 1100D liveview screen, the ED80 will be far more forgiving than a 10" Reflector and a lot easier to get on with, i would forget the 8" not because is no good, its very good but the 10" will be better, the Canon 1100D refurbished of E-Bay around £200, the 1100D is a nice learning tool, if you still maintain the imagine bug you will need a CCD, Filter Wheel, Auto guiding, i think you will find the the ED80 and the 10" reflector properly don't use the same CCD type....Good luck and clear sky's....:)

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