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New ES 140mm f6.5 FPL-53 Scope - Pictures and Impressions

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#26 Tyson M

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Posted 09 February 2019 - 09:16 PM

This scope sounds like a winner from ES! 

Definitely not cheap: a premium scope from this maker. 


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#27 SkyHunter1

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Posted 09 February 2019 - 09:18 PM

2585,

The tube ring only has one hole, so I don't have a choice there. The screws are in tight and deep into the tube ring assembly. The much wider Losmandy plate is flush to the flat bottom of the tube rings, making much more total contact than the Vixen. That should improve the stability substantially I would think. I agree with you in that I would have liked 2 screws as well just for peace of mind, but don't think its going anywhere and its definitely more solid than before.

 

Regards,

Skyhunter1


Edited by SkyHunter1, 09 February 2019 - 09:20 PM.

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#28 dscarpa

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Posted 10 February 2019 - 11:19 AM

 Excellent review! Thanks. Skyhunter where did you get that deal on the ES 140 for $4,300? David


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#29 SkyHunter1

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Posted 10 February 2019 - 12:10 PM

Dscarpa,

Its a long and involved story where it was black friday, a little wheeling and dealing, and a little luck. I will tell you this though...

 

https://explorescien...ges/mailinglist

 

If you sign up for the Explore Scientific mailing list, you get 10% off your first purchase

 

That brings you to $4500 for the ED140 and $2700 for the ED115... A nice little discount smile.gif

 

Hope It helps you and others in the community get their dream scopes.

 

Regards,

Skyhunter1


Edited by SkyHunter1, 10 February 2019 - 12:31 PM.

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#30 woody wood

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Posted 10 February 2019 - 11:14 PM

Sounds like a great deal. Thanks SkyHunter. I’m sure this is going to be very helpful to people looking to step up to a larger refractor. 


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#31 SkyHunter1

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Posted 11 February 2019 - 10:03 AM

Woody,

Doing my best to provide as much info as I can. If you have any questions please feel free to post them here.

 

Regards,

Skyhunter1



#32 AxelB

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Posted 11 February 2019 - 11:04 AM

If only they could offer a 127mm f6.5 triplet!

The focal length and light grasp of my AR127 is just perfect for me. If I could just upgrade it to an fcd100 or fpl53 triplet that would make it much more versatile.

115mm is a bit small for visual and 140 is a bit on the heavy side for my AVX and my unbalanced Stellarvue M2. There’s the fcd100 127mm but it’s f7.5 so not so good for wide field.

Keep us posted about that 140mm f6.5. If it can withstand the test of astrophotography with bright stars without too much CA, for sure a 127mm f6.5 would be even better. Maybe they could even make a 5" f6...

Edited by AxelB, 11 February 2019 - 11:08 AM.

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#33 pollux

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Posted 11 February 2019 - 11:28 AM

This one IMO is the best balance/compromise between size and aperture.

6-inch aperture will be ideal but the typical focal length is 1200mm which makes that tube too long to be practical in terms of handling.


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#34 SkyHunter1

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Posted 11 February 2019 - 03:36 PM

Axel,

A 5" f/6 would be a fast scope at that aperture and probably cost quite a bit more as a result. Being that the 127mm is one of ES's most popular scopes, I agree that a f/6-f/6.5 model would be a sweet spot for a lot of people. 

 

I'm also thinking if the ED115 isn't sufficient for your visual purposes at 632mm and the ED140 is good enough but too heavy at 910mm, that a 127mm f/6 at around 762mm FL wouldn't be vastly better for visual and probably only within 2 or 3 pounds of the ED140. (the ED115 is 16 pounds, and the ED140 is 21)

 

I do agree if they made a 127mm model at f/6.5 people would flock to it if it was priced right.

 

I think Pollux is correct in that the ED140 is the best balance between size and aperture. The ED115 would have been a killer wide-field astrograph level apo though...

 

I hoping to get some lunar AP in the next few days (snowstorm coming) and some deep sky in the next month or so when the weather gets a little better by the beach where I image. 

 

I'll keep you all posted smile.gif

 

Regards,

Skyhunter1


Edited by SkyHunter1, 11 February 2019 - 03:44 PM.


#35 droe

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Posted 11 February 2019 - 09:33 PM

That scope is absolutely beautiful. I have the 127mm CF FCD100 version. The biggest wow factor for me was the Moon; I never expected it to be so crystal clear. Anyway, it would be great to see a side-by-side compare with FCD100 version with a FPL-53 version. People speak so highly of the FPL-53 scopes that I need to see one someday. It must be a real treat.

 

Hope to see some images from that scope. I am looking at getting a ZWO 294MC Pro so and image with that camera would be awesome. 


Edited by droe, 11 February 2019 - 09:33 PM.

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#36 gnowellsct

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Posted 11 February 2019 - 10:05 PM

Explore Scientific has a good rep, this is an ED scope and it sells for $5k which isn't nothing, there's room in that price to build in some performance.

 

Nonetheless:  if you want to evaluate the color accuracy at the scope, an 8.8 mm eyepiece isn't going to do it.  A 140 f/6.5 is 910 mm, divided by 8.8 is 103x.  (I hope I've found the right specs).

 

That is not a rigorous test of a 5 inch scope's ability to hold a sharp image or its color correction.  For that you begin to get into the game at 1x per mm or 140x, and the real test is at 2x per mm or 280x and above, in a 140mm scope.   The FS128 for example shows excellent visual color correction on Jupiter at 296x.  

 

I'm not saying this scope can do it, and I'm not saying it can't do it.  What I'm saying is, an 8.8 mm is not a rigorous test of the ability of the optics to deliver sharp magnification or the quality of the color correction.   That test would require something like a 3 to 3.5mm eyepiece or a 7 mm barlowed 2x, etc.  Since barlows can introduce their own color it's best to have a reliable eyepiece.  There are plossls in this range but I'm not sure if there are good ones suitable for color evaluation.  All the eyepieces I know in this range are pretty expensive (XW 3.5, XO 2.5, Delos 3.5, all pricey).  There's an Orion Stratus at $150 and an Astrotech 3.5 mm for $80, I don't know how its optics hold up.

 

It's quite possible this scope will show little to no chromatic aberration when tested at 2x per mm of aperture, Explore Scientific does good things.  But the report I read above indicates it hasn't really been pushed into the testing zone.  

 

regards

 

Greg N


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#37 Kevin G

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Posted 12 February 2019 - 12:22 AM

I actually like carbon fiber in my refractors as well, with one major caveat: no solar work with them for their black color.

 I'm very interested in this scope, but wanted to know why the black color of the CF would be bad for solar observation?

 

Thanks.


Edited by Kevin G, 12 February 2019 - 12:42 AM.

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#38 SkyHunter1

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Posted 12 February 2019 - 12:41 AM

Greg,

I agree that the scope needs to be pushed harder to get a real test. I know that I need to get closer to 300x to push the optics to the optics enough to make a real determination. My 8.8mm with my 2.5x powermate will bring me to about 260x, but I would want a better eyepiece and forgo the barlow if possible to introduce the least amount of additional optics to make sure any issues I may see are due to the scope itself.

 

My imaging buddy has a set of 2" televues that I asked him if I can borrow a few days ago to make sure that I have a better quality eyepiece fine enough to perform a fair test at higher magnifications. As I am almost exclusively an imager, I don't own eyepieces that fit that bill. You are very correct in that 100x is not pushing the scope to where it can be compared to scopes of similar cost and specifications. I was just giving the scope a preliminary test, but I will most certainly push it harder for the next one.

 

I appreciate your input and my next visual report will address your post.

 

Regards,

Skyhunter1


Edited by SkyHunter1, 12 February 2019 - 01:05 AM.

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#39 SkyHunter1

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Posted 12 February 2019 - 12:46 AM

Kevin,

Although addressed to Tyson, I'm going to assume the black carbon fiber doesn't reflect the the sunlight and that absorption heats the OTA and the air within which would therefore affect the views. 

 

Tyson can correct me if I am wrong in this assumption.

 

Regards,

Skyhunter1


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#40 SkyHunter1

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Posted 12 February 2019 - 12:13 PM

Droe,

To be honest I think the FDC-100 glass would have been sufficient for me. The numbers as compared to FPL-53 were quite close. The reason I chose the ED140 was because its fast... I wanted the speed. FPL-53 is a nice touch and usually standard on high end fast scopes, but I would have taken a fast FDC-100 if it was available. Don't get me wrong though... I like having the FPL-53 :)

 

I will try to do some lunar imaging as soon as the weather permits. I have a 183mc and a 294mc. I will try to use both to get the highest resolution possible.

 

If you're looking at the 294, get it... amazing camera for the price...

 

Regards,

Skyhunter1


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#41 gnowellsct

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Posted 12 February 2019 - 04:14 PM

Greg,

 

 

I appreciate your input and my next visual report will address your post.

 

Regards,

Skyhunter1

Good luck I'm sure it will be a peach.  This is the second post I've seen in a few days of someone evaluating color correction at less than 1x per mm so I'm trying to nudge people towards a little more rigor.  Looks like you're on top of it.  GN


Edited by gnowellsct, 12 February 2019 - 04:15 PM.

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#42 gnowellsct

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Posted 12 February 2019 - 04:22 PM

 I'm very interested in this scope, but wanted to know why the black color of the CF would be bad for solar observation?

 

Thanks.

Because black absorbs heat and doesn't want to let go of it.  You're much better off with white.    Black makes a little daytime oven inside your scope.  I suppose you could get some white construction paper or tinfoil and wrap the scope in it before you take it out, but it will injure your sense of aesthetics.  And when did anyone ever get a date with an apo wrapped in tin foil?

 

There are many other reasons why you want white.  If you get a white refractor you just tell the missus "this is my white refractor" (say, your 4" Explore Scientific ED doublet).  Later on you get a Takahashi 6" triplet apo.  She looks at it and says "is something different there?"  And you say, no, this is my white refractor.  

 

If you move from black to white or white to black you can get in heap big trouble.  Just always have a white refractor.  Call it your white refractor, whether it's an 81 mm Vixen or a TEC 180, it's just a white refractor.

 

Greg N


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#43 Bill Dean

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Posted 13 February 2019 - 09:09 AM

Hi Kevin,

When my carbon fiber ED127 is being used for solar observing it is pointed at the Sun and is impacted as much as any other color, same as my dark blue, black, orange, gold and white telescopes.

Clear skies,
Bill
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#44 Kevin G

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Posted 13 February 2019 - 12:02 PM

Thanks!
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#45 SkyHunter1

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Posted 14 February 2019 - 10:30 AM

Oh Well.... I tried... :(

Tried to get some lunar shots last night but the strong winter winds and high wispy clouds made imaging difficult. Weather has been really bad here in NYC. I was still able to get a couple of pretty good shots in the 20 min I was imaging, but will try again when the conditions are better.

 

I'll be away for a week but will be checking the thread while I'm away. If anyone has any questions, post away :)

 

Also, got the 3" .7 focal reducer from Explore last night... OMG its a monster... Biggest reducer I've ever seen... I'll post some pics later. I'm confident that this reducer will pair well with this scope. 

 

f/4.5 at 1.5 arcsec/px... sounds good to me :)

 

Regards,

Skyhunter1



#46 droe

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Posted 14 February 2019 - 10:52 AM

Oh Well.... I tried... frown.gif

Tried to get some lunar shots last night but the strong winter winds and high wispy clouds made imaging difficult. Weather has been really bad here in NYC. I was still able to get a couple of pretty good shots in the 20 min I was imaging, but will try again when the conditions are better.

 

I'll be away for a week but will be checking the thread while I'm away. If anyone has any questions, post away smile.gif

 

Also, got the 3" .7 focal reducer from Explore last night... OMG its a monster... Biggest reducer I've ever seen... I'll post some pics later. I'm confident that this reducer will pair well with this scope. 

 

f/4.5 at 1.5 arcsec/px... sounds good to me smile.gif

 

Regards,

Skyhunter1

I was thinking about getting that reducer for my 127mm. Give us a report on how well it works when you get it setup. Thanks


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#47 Mr. Mike

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Posted 14 February 2019 - 02:09 PM

Hey - fabulous scope and I like this thread!  I just purchased a 102mm Essentials triplet directly from ES(silver grade refurb) and scored a great deal on it!  Not as nice as your rig but Im in the ES club so to speak now.  Will have it next week and with some luck I can post pics and a quick view report if my upstate, NY weather cooperates, lol!


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#48 John Fitzgerald

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Posted 14 February 2019 - 02:18 PM

Is 1 bolt to fix each tube ring to your plate enough?  I would want 2 minimum. 

The tube rings on my ES ED 152 had only one 6mm threaded hole in each ring.  There were also two smaller unthreaded holes in each ring beside the threaded hole.  I threaded the other four holes to 6mm.  The rings are now held on to the dovetail by six bolts to a 1/2 inch thick solid  aluminum alloy plate machined to Vixen size to fit my Atlas mount.  Rings are 11 inches.apart center to center. The OTA feels very secure.  I think the rigidity of the plate has a lot to do with it.  Some of the stock Vixen style plates are not solid, and look extruded.  My plate is heavy.


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#49 SkyHunter1

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Posted 14 February 2019 - 04:08 PM

I was thinking about getting that reducer for my 127mm. Give us a report on how well it works when you get it setup. Thanks

Droe,

I believe your 127mm scope will work with this reducer as per ES's site:

 

"Recommended for our 127mm and 152mm refracting telescopes, this field flattener/focal reducer boasts fully multi-coated optics and comes with 1 adapter.

 

The field flattener/focal reducer offers 55 mm of back focus from the rear flange. The M42x0.75 adapter is 6.25 mm thick.

 

While technically this was designed for the F/8 system, through user experiences and our subsequent testing we have concluded that our 3-inch field flattener/reducer performs very well with our F/7.5"

 

Since the 127 is 952mm I'm thinking this will work with the 910mm ED140 as well. I had originally posted about the ED140 looking for a focal reducer. As a result of much research, some say that focal ratio is the deciding factor as to whether a given reducer will work. Some state that its focal length.

 

What I've seen is that a given reducer that is rated for a certain focal length is used on another scope within that range it will generally work.

 

If I were to use a FR rated for a 600mm scope on a 900mm scope, I would expect that I will have flattening for 2/3s of the field, and that I would get elongated stars on the remaining 1/3 of the field along the edges. 

 

There seems to be a debate about this, which is why I originally posted about the ED140. I believe that if this will work with a 127mm it'll work with a 140mm that's close to the same focal length. A 127mm being 952mm and a 152mm being 1216mm, I am surmising that the reducer will work well with scopes in this focal length range. In your case I believe that its been tested for your scope. 

 

If anyone can correct me on the above please do... It's nice that ES is allowing me to test with their reducer, but I'm not certain that this will work. Any FR experts here?

 

Either way I'll let you know. I'm thinking targets like Orion, Pleiades, Horsehead, Virgo cluster, Leo triplet, etc. in the ED140 @ f/4.5 632mm will be amazing. Nice and fast... I like that. I've done FOV checks on the astronomy tools site and these targets should frame well with real short sub times using the reducer. 

 

Regards,

Skyhunter1


Edited by SkyHunter1, 14 February 2019 - 04:33 PM.


#50 FTLAUDSKY

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Posted 14 February 2019 - 04:23 PM

WOW...beautiful scope. You are going to have a lifetime of wonderful views/images. ES hit this one out of the park if it performs as well it looks.


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