Tough Triplet Decision - which is Best ?

[PembrokeSteve]

Hi,

I am very keen to upgrade from an Orion ED80 Doublet to something better for DSO imaging.

At present I am imaging with a Canon EOS 600D. I might go down the ZWO CMOS road some day in the future.

I cannot decide which is best out of these two scopes, and hope SGL can help. My choices are as follows:-

1. TS Optics Photoline 90mm f6.6 FPL3 Triplet , approx £1,059.00, combined with APM Riccardi Reducer & 0.75 Flattener, which will bring the scope down to f4.9, approx £359.00. TOTAL = £1,418.00

2. Skywatcher Espirit 100 ED PRO Triplet, approx £1,565, combined with Skywatcher Esprit Field Flattener, approx £155.                TOTAL = £1,720.00

I am well aware that option 2, the Espirit is a superb triplet. However option 1, the 90mm combined with what I believe is a superb Reducer from APM Riccardi, is very tempting to me, along with big savings financially for me.

Any ideas how these two scopes compare with each other, when fitted to the above mentioned Flatteners?

Grateful for any advice on this please,

Regards,

Steve

 

 

[assouptro]

Hi Steve

I cant offer you any advice on the telescopes, but what I can say is that in the past 10 or more years of imaging and wondering which piece of exotic glass will improve my images the most significant leap forward for me was buying a second hand Atik CCD and learning how to image in mono using filters. 

It was honestly a game changer.  I was reluctant as I knew it was going to take me out of my comfort zone but I am so glad I finally took the plunge.

Sorry to throw you a curve ball!

Maybe someone else will be more helpful?

Cheers 

Bryan

[DaveS]

You haven't said if you are guiding. If not, that would be the first thing to address. After that I agree with Bryan, a camera upgrade will make the next biggest improvement. leave the OTA upgrade till later.

[Skipper Billy]

If its a straight choice on scopes then the Esprit would be my choice.

If its how best to improve your setup then my choices would be...

1. Ditch the DSLR in favour of a cooled mono CCD/CMOS

2. Get guiding

3. Upgrade scope.

 

[Zakalwe]

I agree with all of the above. Get guiding and rapidly follow that up with a dedicated cooled astro cam, either OSC or mono. The difference in quality in the data produced by a cooled astro cam compared to a DSLR really is a massive difference. Having lots of low noise data with good star shapes makes it much easier to learn the dark art that is image processing.

The scope is such a small part of the overall DSO imaging malarkey..in fact it can be argued that it's possibly the least important bit. Having a decent mount, autoguiding and low noise data are an order of magnitude more important than a fancy triplet.

 

If I had my time again then I would have ditched the many nights trying to use a DSLR unguided. The camera just wasn't sensitive enough and without guiding I was dumping more subs than I was keeping. Then the frustration of trying to learn how to process with noisy data. The first night that saw the data from a OSC cooled camera I nearly wept with frustration at how much energy was wasted messing with a DSLR.

Edited June 15, 2020 by Zakalwe

[RayD]

Yep, all been mentioned above regarding camera & guiding.  With regards to the 'scopes, I have a TS 80 Photoline and Esprit 100 and of the 2, I would rate the Esprit slightly better overal in terms of image quality.  The dedicated flattener makes it very easy toget excellent stars across the whole field, which I found a little bit of a chore with the TS and the generic flattener(s).

Both very nice instruments, though, and both very capable.

[newbie alert]

I'd go esprit as I have a 80mm and it's superb..100mm be even better.. any reason you want it anymore than native f5.5? 

[Whirlwind]

There are other options that you can consider as well that fall within this type of budget range.  You could include the StellaMira 85mm or William Optics GT81 both with an associated flattener/reducer.  The benefit from the triplet is colour correction (which would be helpful with a DSLR to avoid some bloat).  My concern with a TS telescope is that I'd expect returns to become more difficult as pass the end of the year so may be worth factoring in (returning things to the US is truly a work of the devil with all the paperwork you need) and would expect this to be the same to the EU when the transition period ends (both ways).    

It can be quite difficult to compare two setups identically.  It's rare that people have duplicate scopes just to check certain combinations and even astrobin might have some examples the images will be dependent on seeing, image processing skills etc.  None are likely to be bad (though Melon'y Lemons do occasionally get through) so those that provide pre-checks can be a benefit.  

You will probably see the biggest change when you move to CCD/CMOS with guiding because of the reduction in noise compared to a DSLR.  

[PembrokeSteve]

Hi,

Just to say many thanks for all your excellent advice. I am not yet guiding and am still in the DSLR stage. However I will now take on board your advice and look seriously  into “getting into guiding”  and the possibilities of upgrading from DSLR.

My train of thought has been Triplet, Triplet, Triplet , when my Orion ED80 is more than capable of giving me great images, especially if I progress to guiding and go for a dedicated Astro OSC or Mono camera. To be honest, like many people relatively new to Astro imaging, just the thought of guiding can be scary, because there is the fear of failure and it doesn’t look easy ! Hence my desire to get a scope which can be reduced/flattened down to a fast f4.9. 

Again thanks for advice so far, much appreciated.

Steve

 

[DaveS]

I started off roughly where you are now, with a Megrez 90 ED doublet on an HEQ5 and no guiding. This was a step from an original visual set up, but with the intent of imaging later. I then added a WO flattener and my Canon 550D bodging out pretty dire unguided stuff.

The first big step up was when I started guiding with PHD and controlling the camera through APT, though my PA was still iffy due to having to set up almost from scratch each time, and rushing the PA. I was still using the DSLR so compounding the sins.

Big step number two was when I could afford a cooled mono CCD and filters, this made almost (Or possibly more) as much of an improvement as guiding.

From there on there have been more steps up, but they have been largely incremental rather than game-changing, the first two were the big ones.

[assouptro]

Just thought I’d add a couple of comparison images from the same scope, with different cameras. 

m27, canon 6D, lx200 12” with 6.3 focal reducer field flattener mid summer 

 

same scope and flattener with an Atik 460 and filters also round midsummer. The smaller chip of the Atik gives a smaller Field of view.

I still have a lot to learn when it comes to processing. 
both were guided, and as others have said, guiding is probably your first real step to improve images, without it you’ll struggle to take long enough sub frames. 
phd guiding is fairly straight forward. There is always a learning curve but there is also someone on this site ready to help should you come across a stumbling block. I know, I have been pulled out of the mire of frustration often enough! 
What ever decision you make just try and enjoy the night sky and remember why you want to pursue this hobby! 

cheers 

Bryan
 

 

[Louis D]

On 14/06/2020 at 19:28, PembrokeSteve said:

1. TS Optics Photoline 90mm f6.6 FPL3 Triplet

Well, I use mine visually, and it's quite nice.  Star points are nice and tight and pretty much color free at best focus.  Airy disks are apparent on one side of focus, but not so much the other.  Is it a huge step up from my AT72ED (FPL-51 doublet)?  No, it is more incremental.  The big step up was from my ST80 to the AT72ED.  Is it as color free as a Newtonian?  No, but the tighter star images make up for it visually.

Photographically?  I think your money might be best spent elsewhere as others above have suggested.  Visually, moving from ED to APO wasn't nearly the game changer I had expected.  It's still not at the color free level of a Newtonian, but there's no central obstruction.

[StuartJPP]

I like to get the most out of what I have already got so in your case a small(ish) outlay to get you guiding will be money well spent as you can use that investment going forwards.

Then take it from there. 

I love it how people say that if they had to do it all again that they would do it differently....I don't think so. Imagine considering a new hobby.....I don't know.....fishing.....and before you even cast off you need to spend £2499.99 on a fishing pole (just the pole), £4500 on a reel, £849 on hooks and fishing line and £750 on waders. You'd never take up fishing in that case.

However investing a rather large sum of money on a new scope and retaining the rest of your imaging setup will most probably end in disappointment.

Just my thoughts.

 

 

[Knight of Clear Skies]

Agree with the above, I'd think more about the camera than the scope. I'd just like to add, guiding isn't essential with a low-read noise CMOS camera. This was taken with 30 second unguided subs using the 1600MM cool.

[newbie alert]

I'd get guiding first, a 80ed punches above it price tag in performace.. you can adapt the finder into a guider with an adapter, so all you would need is a guide camera, and adapter.. a rs232 cable to usb or a st4 cable..and downloaded phd2..

What mount are you using?

[PembrokeSteve]

Hi,

I am so glad I submitted my “Triplet query”. After all your advice, I am putting the triplet idea on the back burner  for now, and instead will concentrate on beginning guiding and utilising the gear I already have - mainly my Orion ED80 and NEQ6PRO mount. It will pay off dividends for me when I can guide, because then I will also be able to get some use out of my Vixen VC200L, which up to now , I have only really used on the Moon and Planets.

I will also start looking a ccd cameras !

Many thanks again,

Steve

[Zakalwe]

7 hours ago, PembrokeSteve said:

I will also be able to get some use out of my Vixen VC200L, which up to now , I have only really used on the Moon and Planets.

Imaging at 1900mm and f9 is a tough gig...

[DaveS]

Thinking about it, possibly the biggest improvement in my imaging was the most expensive and most recent, when I upped sticks and moved from light polluted London to dark sky Dorset, Bortle 8 SQM 18.25 to Bortle 4-3 SQM 21.66. Galaxies are now, at last, doable.