I'm using the Esprit 120; several of my most recent images have been taken with it. You can see them in my astrobin gallery (see signature).
Pros: By far the sharpest scope I've ever imaged with (compared to ED100, ED80, RC8).
Cons: QA issues (focuser not adjusted properly on delivery, focuser locking lever fell off) and missing accessories, all of which required me chasing up the distributor. Ultimately got everything sorted but it took a while.
Never had to adjust focus throughout the night before on any of the other aforementioned scopes, but this one needs it done very frequently. Most nights I can see the FWHM go up in every 8min sub. You'll either need lower standards for focus, be happy babysitting it a lot, or automated focusing.
Bottom line: Very solid performer. Would buy again.
I'm using the Esprit 120; several of my most recent images have been taken with it. You can see them in my astrobin gallery (see signature).
Pros: By far the sharpest scope I've ever imaged with (compared to ED100, ED80, RC8).
Cons: QA issues (focuser not adjusted properly on delivery, focuser locking lever fell off) and missing accessories, all of which required me chasing up the distributor. Ultimately got everything sorted but it took a while.
Never had to adjust focus throughout the night before on any of the other aforementioned scopes, but this one needs it done very frequently. Most nights I can see the FWHM go up in every 8min sub. You'll either need lower standards for focus, be happy babysitting it a lot, or automated focusing.
Bottom line: Very solid performer. Would buy again.
could it be because it is that much sharper that you notice the focus drift more easily?
could it be because it is that much sharper that you notice the focus drift more easily?
That's my guess as well. Maybe the spot size on the others was just so big than any drift was just unnoticeable. Still, it means to take advantage of it, you probably have to buy/make an auto focusing rig, which I didn't consider when making the purchase originally.
I ended up with Lee's focuser and yes it was not good , I have since spent a lot of time adjusting , adjusting , I ended up pulling it completly down and cleaning , re-lubing , adjusting ,,, adjusting . more adjusting .
Did I mention I had to adjust it ??? , its so finickey , but seriously it is a good focuser now and its just not really good enough on a scope of this caliber ( flag ship scope ) that this one slipped thru their QC ,,,
But now its as good as any I have ever had bar the FT I once had but it holds my 1kg Axiom 31mm LX in the vertical position without slippage and it lifts it easily .
Its a shame such a thing was allowed to get thru QC .
lol. Sorry Brian, I shouldn't laugh. I had been thinking recently, "y'know, I probably should have just kept that focuser, I'm sure it wasn't as bad as I recall." Hearing you say the above makes me glad I didn't keep it and try and motorise it.
Bart , its a R&P , a very nicely machined rack and pinion , great 10/1 reduction race , quality drive bearings , but the problem is in its overely complex adjusting system , a real head %$#k as you need to push/pull the opposing 1mm and 1.5mm allen head screws to get any feel , over and over and over an.... oh no !!! you over tightened the left rear ,,,,
back to the beginning ,,,
Again .over .... I cant count the times I dropped one of these tiny baby allen keys onto the dark workshop floor .
Once set now , it seems to be good , touch wood but I have used it lots with big Nagler and Celestron eyepieces and it seems to be holding its own .
Lee , I love a problem , its what I do ,,,,
,,, bring it on .
But thats only part of this scope , how are the optics ? that was the origonal Q and sorry for hi-jacking the thread Bart , but from what I have seen in the WWW these are as good as the best APO's out there no matter what price .
They are as I said before a 'FlagShip' telescope for Synta .
Once sorted well up to my visual self with my 127mm iStar .
Brian.
Last edited by brian nordstrom; 12-04-2016 at 10:23 PM.
All good Brian, info on the focuser is still very relevant.
I'm not sure if every scope would need the focuser adjusted and I hadn't factored in a FT focuser at this stage as I'm starting from scratch again and am buying everything from mount to camera to scope, etc.
Reviews on the web (accuracy??) generally indicate the focuser is quite good.
Oh..and the field flattener is built into the scope?
The field flattener isn't built in to anything, you have to get the correct spacing for it with adapters etc.
I'm not using the flattener at all, I find I don't need it with my small sony sensor. I've never actually used it so I can't provide any more advice on that.
I don't think the focusers are inherently crap, as I said in my original post, it's the QA that's terrible. You might get a good one, you might not.
I have the 100 and don't have a problem with the focuser. If I stuck something heavy on the back and pointed it at zenith it might slip a bit if unlocked, but nothing that couldn't be tightened up.
FWIW I focus then lock, regardless of whether it's carrying a DSLR or CCD+filter wheel, etc.
OK, so I think I get it now. The field flattener comes with the scope when you purchase it?
And much the same as any field flattener, it needs to be attached to the front of the imaging train to a specified setting (in this case 75mm?) to give correct distance to the chip.
Does the flattener support the threading on of a light pollution filter?
In Australia, the flattener comes with the scope, but it's up to the country-specific distributor as to what's included.
The scopes include the necessary adaptors to give the correct spacing with a Canon DSLR. In the case of the 120 and 150, this is an extension tube that threads on to the rear of the flattener. On the inside of this extension tube there is a 2" filter thread. For the smaller scopes, it's possible to use a third party adaptor that provides similar capabilities (Baader make a M48 to Canon EOS adaptor that a low-profile 2" filter can be threaded into).
Cool, I thought from the speil that it had a flattener in the back of the scope for some reason.
Appreciate the help, I'll call Bintel tomorrow as their website does not list the flattener as "in the box".
I bought an Esprit 80 recently and the R&P focuser slips easily.
The focuser looks fairly well designed but is way out of adjustment and worse, they've thread locked everything making it difficult to adjust.
There are two Teflon slides with two screws each that I tightened ~1/16 to 1/8th turn to remove the wobble from the drawtube and provide a little friction. Originally the drawtube rolled in an out just tilting the scope when I had the pinion removed. I didn't pull the drawtube all the way out as I recall reading somewhere that parts are held in place by the drawtube.
I want to get the micro-focuser off so I can put more tension on the bearing to increase load carrying ability, but the grub screw is so tight I've rounded out the hex head, so now I've ordered a screw extractor set to get that out. Once the micro-focuser bearing is tightened the focuser should perform very well.
The optics look fairly good, just a slight dent in a star halo.
Small allen heads stripout the heads because the turning pressure is too hard & too fast, using our fingers we can't help but do it, if you drill a small bit of dowel to fit the key into this gives you a handle for leverage too put a slow constant force on the screw, to defeat the Loctite use a small soldering iron(no solder, remove it) & heat the key while using SLOW finger pressure to undo the screw, take your time the heat softens the Loctite, if the head is stripedout do the same with an ezyout,I know heat expands but this works, 35 yrs as a bike mechanic has proven it.
Thanks for the advice Geoff, this one's got me beat though so I'm giving up before I wreck it. This particular grub screw is down inside a hole making it extra difficult to work on. The focuser holds a dslr and reducer now that there's a bit of tension on the drawtube.
Here's a photo of the pinion block removed from the focuser. You can see how the brake works, clamping onto the sides of the rack.
The pinion to rack mesh is set using the 8 push/pull screws.
Thanks for the advice Geoff, this one's got me beat though so I'm giving up before I wreck it. This particular grub screw is down inside a hole making it extra difficult to work on. The focuser holds a dslr and reducer now that there's a bit of tension on the drawtube.
Here's a photo of the pinion block removed from the focuser. You can see how the brake works, clamping onto the sides of the rack.
The pinion to rack mesh is set using the 8 push/pull screws.
Is it one of the 4 still in the block with the adjuster knobs on it?
Could try removing the rubber finger grips, heating screw area with heat gun/hairdryer, put long end of key in it, give key a hit to drive it in a bit & instead of trying to back out screw turn it all the way thru.
Next trick is to heat, use a new drill bit the size of the stripped screw head, cordless drill & as slow as possible drill screw out, we are not trying to put a hole thru the screw(yet) but to have the bit bite into the screw & turn it'self out the bottom of the block, keeping the heat on low while you do it helps(3rd hand)keeps any Loctite soft.
Mods apologies for the hi-jack.
I ended up with Lee's focuser and yes it was not good 
, I have since spent a lot of time adjusting , adjusting , I ended up pulling it completly down and cleaning , re-lubing , adjusting ,,, adjusting .
more adjusting .
Bart , its a R&P , a very nicely machined rack and pinion , great 10/1 reduction race , quality drive bearings , but the problem is in its overely complex adjusting system , a real head %$#k as you need to push/pull the opposing 1mm and 1.5mm allen head screws to get any feel , over and over and over an.... oh no !!! you over tightened the left rear ,,,,
.over .... I cant count the times I dropped one of these tiny baby allen keys onto the dark workshop floor 
.
I love a problem , its what I do ,,,,
