Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

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Jaq1967
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Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#1

Post by Jaq1967 »


Moving up from my Skywatcher 150P (150/750) what would be a big improvement from this scope? Visual and imaging.

Skywatcher 200P-DS or Skywatcher Quattro 8-S

I would like the 8-CF, but cannot see anyone selling the carbon tube in the UK. Other than weight and cool down time is the price a really worth it? I think they go for about £400-500 more than the 200P-DS.

Anyway, back to the two in question: Which one and why? The price different is £126.00 between the two OTA from the Tring Astronomy Centre. Is the extra £126.00 justifyable?

Or... how about a 190MN DS-PRO??? £755.00 more than the 200P-DS. I could get the 200P-DS and the 100ED DS Pro for the same money.

My mount is a HEQ5 Pro so the 190MN may be pushing it?

What say the forum???

:)
Telescopes: Altair Astro Starware 102ED-R, SW P150 reflector, SW SkyMax127 mak, Meade ETX90 mak, SW Startravel 80 Table Top Telescope
Mount: HEQ5-Pro, EQ3-2
Camera: Pentax K-50, Pentax K-70, Altair Hypercam 183C Pro TEC
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#2

Post by JayTee »


Hi,

When you want to go bigger for visual, don't drag AP into that rationale. AP does not need you to go bigger. This is the reason why most of the imagers have imaging scopes and visual scope. It sounds like it may be time for you, if you're interested and can afford it, to go this route.

Cheers,
JT
∞ Primary Scopes: #1: Celestron CPC1100 #2: 8" f/7.5 Dob #3: CR150HD f/8 6" frac
∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO
∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5
∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros.
∞ Mounts: iOptron CEM70AG, SW EQ6, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000
∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3
∞ Binos: 10X50,11X70,15X70, 25X100
∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°

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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#3

Post by notFritzArgelander »


JayTee wrote: Sun Sep 15, 2019 7:54 pm Hi,

When you want to go bigger for visual, don't drag AP into that rationale. AP does not need you to go bigger. This is the reason why most of the imagers have imaging scopes and visual scope. It sounds like it may be time for you, if you're interested and can afford it, to go this route.

Cheers,
JT
I agree. For AP it's speed not aperture so much unless you are really going after extremely faint objects. Why not a nice 150mm f4 Newt for AP to go with using your present scope for visual? https://optcorp.com/products/ao-at6in-6 ... agQAvD_BwE

I used to have the 8" f4 of this paired with an 8" f6.3 for visual. That was a nice combo and I might try to recreate it.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#4

Post by dritter »


When you say 190MN, I assume you mean the Mak-Newt MN190, or so it's known as in North America.

If so, the MN190 will be too much for an HEQ5.

My NEQ6-Pro barely carries mine well enough for visual use. And it won't carry it when loaded up with my AP gear. Others may vary in this opinion, technically it's within the spec. And I do know of at least one imager who very successfully uses an AZ-EQ6 with his.

But even so, on an EQ6 in any form, the MN190 still needs at least three counterweights for it to balance properly. So, it's unlikely that an HEQ5 is up to the task.

The reason is that the MN190 is quite a bit heavier than it appears to be when compared to a regular Newtonian. The meniscus lens up front turns out to be a rather formidable hunk of glass. And the tube is kind of long, and each end has cast parts to hold the mirror and meniscus. So it all adds up and when fully decked out, mine weighs almost as much an 11" SCT.
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#5

Post by Jaq1967 »


I gain nothing then from moving from a 6" f5 (150/750) to a 8" f4 (Quattro, being 200/800) - except for the extra f1 difference?

Seems like a pointless upgrade if going bigger means no massive improvement in image capability?

I think the 190NM isn't going to do anything for me and seeing my HEQ5 Pro isn't up for the extra weight then no point looking at it.

The Skywatcher Quattro 8CF (Carbon) is discontinued. No idea why.

So, the choice is between the 200PDS (f5) and the Quattro 8S (f4) - (Now known as the Quattro 200P). I gain nothing with the 200PDS on my existing 150P. Both are f5. So unless you are doing visual, for AP they offer nothing new? Not to mention lumbering a larger and heavier scope for my mount and essentially more to catch the slightest breeze!
Telescopes: Altair Astro Starware 102ED-R, SW P150 reflector, SW SkyMax127 mak, Meade ETX90 mak, SW Startravel 80 Table Top Telescope
Mount: HEQ5-Pro, EQ3-2
Camera: Pentax K-50, Pentax K-70, Altair Hypercam 183C Pro TEC
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#6

Post by JayTee »


So, the choice is between the 200PDS (f5) and the Quattro 8S (f4) - (Now known as the Quattro 200P). I gain nothing with the 200PDS on my existing 150P. Both are f5. So unless you are doing visual, for AP they offer nothing new? Not to mention lumbering a larger and heavier scope for my mount and essentially more to catch the slightest breeze!
You are correct. In fact you will make the situation worse, like you said, by adding the additional weight on the mount.

Also, typically, when someone asks for a recommendation when they currently own a 6" newt we say go up 4" minimum to see a significant improvement in the visual presentation from a telescope. So in your case that would mean a minimum of a 10" telescope.

Cheers,
JT
∞ Primary Scopes: #1: Celestron CPC1100 #2: 8" f/7.5 Dob #3: CR150HD f/8 6" frac
∞ AP Scopes: #1: TPO 6" f/9 RC #2: ES 102 f/7 APO #3: ES 80mm f/6 APO
∞ G&G Scopes: #1: Meade 102mm f/7.8 #2: Bresser 102mm f/4.5
∞ Guide Scopes: 70 & 80mm fracs -- The El Cheapo Bros.
∞ Mounts: iOptron CEM70AG, SW EQ6, Celestron AVX, SLT & GT (Alt-Az), Meade DS2000
∞ Cameras: #1: ZWO ASI294MC Pro #2: 662MC #3: 120MC, Canon T3i, Orion SSAG, WYZE Cam3
∞ Binos: 10X50,11X70,15X70, 25X100
∞ EPs: ES 2": 21mm 100° & 30mm 82° Pentax XW: 7, 10, 14, & 20mm 70°

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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#7

Post by notFritzArgelander »


Jaq1967 wrote: Mon Sep 16, 2019 2:51 pm I gain nothing then from moving from a 6" f5 (150/750) to a 8" f4 (Quattro, being 200/800) - except for the extra f1 difference?

Seems like a pointless upgrade if going bigger means no massive improvement in image capability?

I think the 190NM isn't going to do anything for me and seeing my HEQ5 Pro isn't up for the extra weight then no point looking at it.

The Skywatcher Quattro 8CF (Carbon) is discontinued. No idea why.

So, the choice is between the 200PDS (f5) and the Quattro 8S (f4) - (Now known as the Quattro 200P). I gain nothing with the 200PDS on my existing 150P. Both are f5. So unless you are doing visual, for AP they offer nothing new? Not to mention lumbering a larger and heavier scope for my mount and essentially more to catch the slightest breeze!
You gain a little in resolving power. The 6" has 0.95 arc seconds resolution, the 8" has 0.71 but you will only see that on nights of above average seeing where the atmosphere allows better than 1 arc second resolution. On average nights of about 2 arc second seeing you won't be able to tell.

Visually you gain in limiting magnitude for stars, point sources. The 6" has a (Baker) limiting magnitude of 12.7 and the 8" has 13.3. I find the Sidgwick limiting magnitudes more useful for which the limits are 14.6 and 15.2 but the human eye is fickle YMMV.

As far as AP is concerned the figure of merit I use is the square of the aperture divided by the square of the f ratio. That's where you'd see a difference. It's a measure of the relative anergy delivered to each pixel of the sensor. By that measure the 8" will give the same signal to noise ratio 2.8 times faster. So you'll get good images much quicker.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#8

Post by notFritzArgelander »


To compare with getting a 6" f4 that would give you a 1.6 faster exposure time advantage.

The 6" f4 has a 600 mm focal length so it would be easier to guide for AP than the 8" f4 at 800mm.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#9

Post by Jaq1967 »


notFritzArgelander wrote: Mon Sep 16, 2019 9:39 pm
Jaq1967 wrote: Mon Sep 16, 2019 2:51 pm I gain nothing then from moving from a 6" f5 (150/750) to a 8" f4 (Quattro, being 200/800) - except for the extra f1 difference?

Seems like a pointless upgrade if going bigger means no massive improvement in image capability?

I think the 190NM isn't going to do anything for me and seeing my HEQ5 Pro isn't up for the extra weight then no point looking at it.

The Skywatcher Quattro 8CF (Carbon) is discontinued. No idea why.

So, the choice is between the 200PDS (f5) and the Quattro 8S (f4) - (Now known as the Quattro 200P). I gain nothing with the 200PDS on my existing 150P. Both are f5. So unless you are doing visual, for AP they offer nothing new? Not to mention lumbering a larger and heavier scope for my mount and essentially more to catch the slightest breeze!
You gain a little in resolving power. The 6" has 0.95 arc seconds resolution, the 8" has 0.71 but you will only see that on nights of above average seeing where the atmosphere allows better than 1 arc second resolution. On average nights of about 2 arc second seeing you won't be able to tell.

Visually you gain in limiting magnitude for stars, point sources. The 6" has a (Baker) limiting magnitude of 12.7 and the 8" has 13.3. I find the Sidgwick limiting magnitudes more useful for which the limits are 14.6 and 15.2 but the human eye is fickle YMMV.

As far as AP is concerned the figure of merit I use is the square of the aperture divided by the square of the f ratio. That's where you'd see a difference. It's a measure of the relative anergy delivered to each pixel of the sensor. By that measure the 8" will give the same signal to noise ratio 2.8 times faster. So you'll get good images much quicker.
Thanks for that... all very technical. A real learning curve this.

We talk a great deal about the lens/scope and its ability to deliver information to whatever it sends this information too. How about the latter? The quality of the receiver, the thing that receives this information? The eye? The Sensor? Camera; be it CCD, CMOS sensor, a dedicated Astro camera or DSLR (modded or un-modded) is of equal, if not greater, consideration when pairing up with the scope? A good camera could afford to work on a less 'fast' and/or smaller scope?

I have an Altair Astro Hypercam 183C Pro TEC. I've yet to have tested this properly in the night sky. It seems to be fairly medium (to high?) in spec. Being dedicated (a reason for purchasing it), I'm kind of guessing it is a better option for AP than a modded DSLR? Is it better? What could I get away with (scope-wise) using this type of camera? I used to use an old Pentax KX (un-modded) with fairly good results, considering it isn't really designed for AP.

Thanks for your advise on this. I'm kind of thinking now maybe I should consider refractors as scope options for DSO AP now, and not just reflectors? They are lighter and smaller. I dare say more expensive? Evostar: 72ED, 80ED, 100ED and/or 120ED (...range of DS Pro). Hmmm....

Finally, I guess the bottom line is having the tools to hand is what you can do with them and how good you are at using those tools pre and post processing.
Telescopes: Altair Astro Starware 102ED-R, SW P150 reflector, SW SkyMax127 mak, Meade ETX90 mak, SW Startravel 80 Table Top Telescope
Mount: HEQ5-Pro, EQ3-2
Camera: Pentax K-50, Pentax K-70, Altair Hypercam 183C Pro TEC
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#10

Post by notFritzArgelander »


Jaq1967 wrote: Tue Sep 17, 2019 3:49 am
notFritzArgelander wrote: Mon Sep 16, 2019 9:39 pm
Jaq1967 wrote: Mon Sep 16, 2019 2:51 pm I gain nothing then from moving from a 6" f5 (150/750) to a 8" f4 (Quattro, being 200/800) - except for the extra f1 difference?

Seems like a pointless upgrade if going bigger means no massive improvement in image capability?

I think the 190NM isn't going to do anything for me and seeing my HEQ5 Pro isn't up for the extra weight then no point looking at it.

The Skywatcher Quattro 8CF (Carbon) is discontinued. No idea why.

So, the choice is between the 200PDS (f5) and the Quattro 8S (f4) - (Now known as the Quattro 200P). I gain nothing with the 200PDS on my existing 150P. Both are f5. So unless you are doing visual, for AP they offer nothing new? Not to mention lumbering a larger and heavier scope for my mount and essentially more to catch the slightest breeze!
You gain a little in resolving power. The 6" has 0.95 arc seconds resolution, the 8" has 0.71 but you will only see that on nights of above average seeing where the atmosphere allows better than 1 arc second resolution. On average nights of about 2 arc second seeing you won't be able to tell.

Visually you gain in limiting magnitude for stars, point sources. The 6" has a (Baker) limiting magnitude of 12.7 and the 8" has 13.3. I find the Sidgwick limiting magnitudes more useful for which the limits are 14.6 and 15.2 but the human eye is fickle YMMV.

As far as AP is concerned the figure of merit I use is the square of the aperture divided by the square of the f ratio. That's where you'd see a difference. It's a measure of the relative anergy delivered to each pixel of the sensor. By that measure the 8" will give the same signal to noise ratio 2.8 times faster. So you'll get good images much quicker.
Thanks for that... all very technical. A real learning curve this.

We talk a great deal about the lens/scope and its ability to deliver information to whatever it sends this information too. How about the latter? The quality of the receiver, the thing that receives this information? The eye? The Sensor? Camera; be it CCD, CMOS sensor, a dedicated Astro camera or DSLR (modded or un-modded) is of equal, if not greater, consideration when pairing up with the scope? A good camera could afford to work on a less 'fast' and/or smaller scope?

I have an Altair Astro Hypercam 183C Pro TEC. I've yet to have tested this properly in the night sky. It seems to be fairly medium (to high?) in spec. Being dedicated (a reason for purchasing it), I'm kind of guessing it is a better option for AP than a modded DSLR? Is it better? What could I get away with (scope-wise) using this type of camera? I used to use an old Pentax KX (un-modded) with fairly good results, considering it isn't really designed for AP.

Thanks for your advise on this. I'm kind of thinking now maybe I should consider refractors as scope options for DSO AP now, and not just reflectors? They are lighter and smaller. I dare say more expensive? Evostar: 72ED, 80ED, 100ED and/or 120ED (...range of DS Pro). Hmmm....

Finally, I guess the bottom line is having the tools to hand is what you can do with them and how good you are at using those tools pre and post processing.
The thing about the little analysis I did is that it is independent of the camera sensor. Whatever camera you use the 8" will get you to a good S/N ratio ~2.7-2.8 times faster. Now the business of optimizing the camera requires more math than I've done. But factors like thermoelectric cooling are certainly important.

Many folks recommend starting with a small refractor for easier guiding. I think starting off with something like a 500-600mm focal length is good. There's a charming little book by Stefan Seip, Digital Astrophotography which comes with downloadable data sets that you can use to practice processing.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#11

Post by Benjamin »


Something else to consider with an f4 Newt and imaging is the degree to which collimation matters. Mechanical alignment and general stability need to be really good and the coma corrector (which I think is mandatory) needs to be the right distance from the sensor. It’s taken me a good while to get close to round stars across an image, which boiled down to a well centered secondary and a tightening up of the focuser tube. Even some of the best images from these scopes show a bit of aberration in one or two corners. Quite a few who post their grievances on forums seem to give up imaging at f4 in frustration quite readily! Personally I love it. The amount of light I can collect at f4 in one session is amazing. If speed is a priority however the new RASA scopes image at f2! These are probably on the too heavy side for an HEQ5. If considering refractors (no messing about with collimation) I would ‘ideally’ be looking at a triplet refractor for imaging. Doublets tend not to focus blue light as well as the other wavelengths which can result in some blue bloating around stars. An Esprit 80 would be top of my list. The pixel size of the camera you have (2.4um) also suits the focal length of the Esprit 80.
Scopes:Skywatcher f5 12" Dob, f4 8” Quattro, Esprit 100
Mounts:Skywatcher EQ6-R (EQMod)
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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#12

Post by yobbo89 »


The skywatcher quattro is an extra 50mm fl over your Current 150p scope, not much of a resolution gain, it's an f4 which is better over your f5, I think a 20% improvement?, so it'll Collects light faster, an f4 scope requires an expensive coma corrector aswell, the faster the optics the better the correction is needed for coma. And then there's more weight to the mount.

The skywatcher 200p offers an extra 250mm fl over your 750 mm fl 150p at the same f ratio, still not a massive Improvement in resolution, there's two things to really look for in a scope for astrophotgraphy, focal length/ resolution, and optics speed. ( and the extras weight, ca, coma, ectt).

F5 is going to be more forgiving in price and with correctors, collimation.

If you want a longer focal length and faster imaging setup then prepare to spend $$ + mount upgrade.

I'm not sure what type of exact load your mount can take but you might be better off going with a refractor, deal with the longer expusure times if you want a longer fl model or get a short fl refractor if you would like a wider shot
scopes :gso/bintel f4 12"truss tube, bresser messier ar127s /skywatcher 10'' dob,meade 12'' f10 lx200 sct
cameras : asi 1600mm-c/asi1600mm-c,asi120mc,prostar lp guidecam, nikkon d60, sony a7,asi 290 mm
mounts : eq6 pro/eq8/mesu 200 v2
filters : 2'' astronomik lp/badder lrgb h-a,sII,oIII,h-b,Baader Solar Continuum, chroma 3nm ha,sii,oiii,nii,rgb,lowglow,uv/ir,Thousand Oaks Solar Filter,1.25'' #47 violet,pro planet 742 ir,pro planet 807 ir,pro planet 642 bp ir.
extras : skywatcher f4 aplanatic cc, Baader MPCC MKIII Coma Corrector,Orion Field Flattener,zwo 1.25''adc.starlight maxi 2" 9x filter wheel,tele vue 2x barlow .

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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#13

Post by yobbo89 »


The 190 mak looks nice, are they really coma free? I guess the pro is you don't have to fork out a few hundred for a Corrector, also no star diffraction spikes.,

BTW out of the two skywatchers I would pick the 200p, f5 is easier to deal with and you'll get a little bit more imaging resolution
scopes :gso/bintel f4 12"truss tube, bresser messier ar127s /skywatcher 10'' dob,meade 12'' f10 lx200 sct
cameras : asi 1600mm-c/asi1600mm-c,asi120mc,prostar lp guidecam, nikkon d60, sony a7,asi 290 mm
mounts : eq6 pro/eq8/mesu 200 v2
filters : 2'' astronomik lp/badder lrgb h-a,sII,oIII,h-b,Baader Solar Continuum, chroma 3nm ha,sii,oiii,nii,rgb,lowglow,uv/ir,Thousand Oaks Solar Filter,1.25'' #47 violet,pro planet 742 ir,pro planet 807 ir,pro planet 642 bp ir.
extras : skywatcher f4 aplanatic cc, Baader MPCC MKIII Coma Corrector,Orion Field Flattener,zwo 1.25''adc.starlight maxi 2" 9x filter wheel,tele vue 2x barlow .

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Re: Skywatcher 200P-DS or Quattro 8S (CF - but can't find them anywhere!)

#14

Post by notFritzArgelander »


yobbo89 wrote: Thu Oct 03, 2019 8:22 pm The 190 mak looks nice, are they really coma free? I guess the pro is you don't have to fork out a few hundred for a Corrector, also no star diffraction spikes.,

BTW out of the two skywatchers I would pick the 200p, f5 is easier to deal with and you'll get a little bit more imaging resolution
Yes all Maksutov Newtonian telescopes are completely free of coma.

Also as I indicated the figure of merit for comparing different apertures and f ratios with regard to exposure times is aperture squared divided by f ratio squared.

So 6" f4 gives 36/16 -> 2.25
"" 6" f5 """""" 36/25 -> 1.44
"" 8" f4 """""" 64/16 -> 4.00
"" 8" f5 """""" 64/25 -> 2.56

So an exposure with an 8" f4 is 2.56/4.00 = 0.64 as long as an 8" f5 to get the same S/N ratio. That's considerably more efficient.

The 190MN is about 1.99 since it is f5.3. So the 8" f4 will need only 1/2 the exposure time.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
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