Skywatcher Esprit 100ED vs William Optics GT102

[PhotoGav]

Hello wise astronomer people.

I am chasing my tail over which telescope to purchase. I am after something in the 550mm range for imaging with my QSI 683 and have identified my three favourite options;

1. Takahashi FSQ106 (530mm, F5, about £5500)

2. William Optics GT102 with Reducer (560mm, F5.5, about £2600)

3. Skywatcher Esprit 100 with Flattener (550mm, F5.5, about £1700)

The problem is that I can’t decide which to go for. I have realistically eliminated the Tak as it is too expensive. If money were no object I think I would just get that and then not be able to blame equipment for my failings as it appears to be the ‘gold standard’ of imaging scopes. I could just save up for one, but that will take a while and I have springtime projects that I need the scope for. So it is down to the SW or the WO.

I have heard very good reports about the SW Esprit and have almost decided to go with that option, but I have that nagging devil on my shoulder whispering in my ear that perhaps the WO would be better. Would it? Does anyone reading this have a WO GT102 and can they please give me their opinion? One bonus with the WO would be the option to use it without the reducer, giving me 703mm at F7 - that could be useful. On the other hand, the SW would do the job very nicely and is the cheapest option. Oh my, choices, choices!

I look forward to hearing your thoughts and experiences of these scopes and to your help with spending my money!

[alan potts]

I have to say I am looking very hard at at a few scopes now myself and whilst I could afford either a Tak or another APM I keep getting drawn magnetically towards the Espirit, this model too. I know one of the Mods has a 150mm Espirit and he know a thing or two about AP, it's good enough for one of the best imagers here or anywhere, so I guess it, or I should say the smaller one, will be good enough for me.

[PhotoGav]

Alan, exactly, I know who you are referring to and indeed his results speak for themselves. That’s why I’m close to hitting the button for the Esprit 100, but just want to be sure I’m not missing something, to be sure!

[Jkulin]

I have the Esprit 100ED and have been blown away with the quality, simply amazing, the focuser is excellent and for £300 you can motorise it within your budget if you look around.

I was so impressed that I went and bought the Esprit 80 as well.

[PhotoGav]

6 minutes ago, Jkulin said:

I have the Esprit 100ED and have been blown away with the quality, simply amazing, the focuser is excellent and for £300 you can motorise it within your budget if you look around.

I was so impressed that I went and bought the Esprit 80 as well.

Excellent, thank you John. That’s quite an affirmation of the Esprit! I use the Lakeside motor focus system, so will definitely connect that up. Another step closer to the Esprit ‘Buy’ button!

[Jkulin]

If you use the lakeside then don't buy a new box just get like I have for the 80 a new motor and mount for just over £100 and switch between them, in fact I am going to fit the motor to the 80 this evening and hopefully get imaging tomorrow night if it stays clear.

[PhotoGav]

3 minutes ago, Jkulin said:

If you use the lakeside then don't buy a new box just get like I have for the 80 a new motor and mount for just over £100 and switch between them, in fact I am going to fit the motor to the 80 this evening and hopefully get imaging tomorrow night if it stays clear.

Absolutely, I have a stepper motor already from a previous scope. I just need the bracket and coupler. 

Do you have any images taken with the Esprit 100 that I could look at, please?

[Jkulin]

Here's a quick grab from my screen of the PacMan in Ha I did at the beginning of January with a full moon, it has been calibrated but apart from that nothing else has been done to it.

 

[ollypenrice]

Second hand Tak FSQ106N. Mine came in at about £2K. The other one, Tom O'Donoghue's, was a bit dearer but was much younger when he bought it. If (unlikely ) Tak offered to swap my Fluorite 106 for their latest Flatfield 106, I would decline. I prefer the old one. It is less sensitive to focus drift while cooling and I don't want to use the reducer. The captain's wheel hasn't made many friends, either. Give me a 106N (or two!)

I love this rig because it works:

Olly

 

[Ken82]

Could anyone tell me how the Espirit and WO scopes get on when using a full frame sensor? Im looking at the espirit 120 or 150 but put off by f7 and lack of focal reducer.

Edited January 28, 2018 by Ken82

[PhotoGav]

Thank you John, do you use the dedicated flattener?

Thank you Olly, that’s what I fear. You have just reintroduced the earlier eliminated FSQ106 and potentially a large dent in my Astro budget (I was thinking that a ‘cheaper scope’ would enable a filter upgrade)! I have seen the occasional second hand one, but generally around £3k. The most recent was in Rome, which makes viewing and collection a bit expensive, but a rather lovely experience! Perhaps I could borrow your rig for a bit - a Mesu 200 and a pair of 106s would be nice...

 

[Jkulin]

Hi Gav, Yes I do use the SW Flattener, but haven't noticed the field any flatter because of it.

[ollypenrice]

11 hours ago, PhotoGav said:

Thank you John, do you use the dedicated flattener?

Thank you Olly, that’s what I fear. You have just reintroduced the earlier eliminated FSQ106 and potentially a large dent in my Astro budget (I was thinking that a ‘cheaper scope’ would enable a filter upgrade)! I have seen the occasional second hand one, but generally around £3k. The most recent was in Rome, which makes viewing and collection a bit expensive, but a rather lovely experience! Perhaps I could borrow your rig for a bit - a Mesu 200 and a pair of 106s would be nice...

 

The last time I looked, Gav, the fluorite 106Ns were not fetching £3000. They have the blue rather than the red bands round them.

Olly

[RayD]

The Esprit 100 really is excellent for the money in my opinion Gav. You could certainly do far worse.

I use mine with the SW dedicated FF and it provides a very flat field across my APS-H sensor, which is only just short of full frame, but I do need to use 2" filters on that.

The stock focuser is very good, and using the Lakeside works a treat on it.

I really can't fault it for the money and wouldn't part with mine.

Below is a pic of mine with the Lakeside on, and one mounted and ready for work. Also is a single 1200s sub of the Pelican (Ha with only a brief stretch & curves) to give you an ideal of the FOV with the APS-H sensor, and the flatness across that FOV.

I honestly don't think you would be disappointed and, as with the Tak, you only have to look to see how few there are available used to give you an indication of how good they are.

Edited January 29, 2018 by RayD

[swag72]

For me the question would be..... will the Tak 106 increase the quality of your images over the Esprit? Personally I would suggest not. The big thing going for the 106 of course is it's massive imaging circle. You'd never have to worry about not being able to get a bigger chipped camera..... but with that change invokes new BIG filters and that's a pretty expensive pill to swallow.

If you want to waste money then a Tak 106 (the new kind!) ... if you want value for money then the Esprit range. If I didn't have the FSQ85's then I'd be buying the Esprit for sure. It makes so much sense.

[PhotoGav]

@Jkulin - the reason I asked was because I noticed significant star elongation in your image’s corners, which looks like coma to me that would normally be sorted by the flattener. As you are using one already, could this be a spacing issue?

@ollypenrice - thank you for that clarification. I will keep my eye out for the 106N, but fear it may not happen in time for my imaging plans. An interesting addition to the problem though! You are the devil on my shoulder!

@RayD - thank you for your post. You have been a strong advocate of the Esprit throughout my research and it is good to see one of your subs, which looks great across the whole image and restores my faith!

@swag72 - absolutely, that is why I had eliminated the Tak, until the French Devil re-opened that argument!!

So far the Esprit has plenty of support, while the WO has zero input / feedback... interesting!

[alan potts]

Sending button pressing thoughts to you from afar. Oscar Wilde, the only way to deal with temptation is to yeild to it.

Alan.

[LightBucket]

50 minutes ago, RayD said:

The Esprit 100 really is excellent for the money in my opinion Gav. You could certainly do far worse.

I use mine with the SW dedicated FF and it provides a very flat field across my APS-H sensor, which is only just short of full frame, but I do need to use 2" filters on that.

The stock focuser is very good, and using the Lakeside works a treat on it.

I really can't fault it for the money and wouldn't part with mine.

Below is a pic of mine with the Lakeside on, and one mounted and ready for work. Also is a single 1200s sub of the Pelican (Ha with only a brief stretch & curves) to give you an ideal of the FOV with the APS-H sensor, and the flatness across that FOV.

I honestly don't think you would be disappointed and, as with the Tak, you only have to look to see how few there are available used to give you an indication of how good they are.

Please forgive me as slightly off topic, but just noticed in your image above of your scope and set up, you have a Pegasus hub, can you tell me if the focuser controller built into that works ok with the Lakeside motor on your focuser..??

Again sorry all for the off topic question, it won’t happen again...

[RayD]

18 minutes ago, LightBucket said:

Please forgive me as slightly off topic, but just noticed in your image above of your scope and set up, you have a Pegasus hub, can you tell me if the focuser controller built into that works ok with the Lakeside motor on your focuser..??

Again sorry all for the off topic question, it won’t happen again...

Yes it works great.  You have to make a lead up as the focuser socket on the Pegasus is RJ12, but it is really easy as Pegasus give you the pin outs on their web site.  I just bought a standard RJ12 flat lead 2m long, cut one end off and soldered on a D sub socket.  The 2m lead was enough to make 2 leads.

Took 20 minutes and focuser works a treat.  

Apologies @PhotoGav

Edited January 29, 2018 by RayD

[Jkulin]

39 minutes ago, PhotoGav said:

@Jkulin - the reason I asked was because I noticed significant star elongation in your image’s corners, which looks like coma to me that would normally be sorted by the flattener. As you are using one already, could this be a spacing issue?

As I said this was just a calibrated image in Ha that I have done nothing else with, I thought that it was better to provide something like that.

No spacing issue as bang on the measurements quoted for it.

[Astroscot2]

Ive been thinking of buying a refractor recently so this thread is of some interest to me,  Ive owned the older FSQ once upon a time and really enjoyed imaging with it.  the only reason I sold it was that I wanted to image at longer local lengths and knew a better mount would make life easier, turned out my EQ8 was not up to the job.  Anyway not having the funds nox for an FSQ Ive been looking at various reviews on a number of refractors, I narrowed it down to either the WO 130,  Esprit 100 or 120, I do fancy the longer focal length of the WO130 & SW120.   Looking at various astro images on line and Rays pelican shot above, The Esprit's FOV looks to be well corrected up to APS which would be fine for me.  Would like to see is individual subs though RGB so I can determine if there is any bloat in the blue channel, narrowband only tells 1/2 the story.

Mark 

[Ken82]

What about a 6 element ts scope as an alternative ? Good value but has anyone got a review ?

https://www.teleskop-express.de/shop/index.php/cat/c224_Flatfield-APO-Refractor-Teleskope.html

[RayD]

9 minutes ago, Jkulin said:

No spacing issue as bang on the measurements quoted for it.

I found mine to be quite critical, and literally down to cutting a 0.3mm spacer from the lid of a spread tub.  Took me a fair while to get it right, but that was over the APS-H sensor, which is pretty big.

[Jkulin]

25 minutes ago, RayD said:

I found mine to be quite critical, and literally down to cutting a 0.3mm spacer from the lid of a spread tub.  Took me a fair while to get it right, but that was over the APS-H sensor, which is pretty big.

Your using the 16200 Ray which correct me if I am wrong is exceptionally critical, I believe with the 383 and my imaging chain that I can't do anything better than what I have, apart from human error and that my focusing could improve which I am working on.

[RayD]

3 minutes ago, Jkulin said:

Your using the 16200 Ray which correct me if I am wrong is exceptionally critical, I believe with the 383 and my imaging chain that I can't do anything better than what I have, apart from human error and that my focusing could improve which I am working on.

No not saying there is anything wrong with yours John, just that I found on my larger sensor the FF was subject to very small adjustments.  I doubt this would be anywhere near as critical on an 8300 sensor, but definitely worth having a play around with (+-1mm) as there can be a small variance in the sensor distance within the camera.