Would a 4 inch apo beat my achromat and maksutov

[Paz]

I am wondering if an apo around 100mm would better my st120/mc127 combination. 

I use my st120 mostly for white light solar with a wedge and solar continuum filter. Would the smaller apo do better in white light solar. In theory the extra aperture if the st120 would help it quite a lot.

Would a 100mm apo do better than my 127mm maksutov on doubles, lunar, etc. Again the extra aperture of the Mak is going to help it.

One 100mm apo costs more than my st120 and mc127 maksutov combined. I'd be interested in hearing any comments.

[John]

25 minutes ago, Paz said:

I am wondering if an apo around 100mm would better my st120/mc127 combination. 

I use my st120 mostly for white light solar with a wedge and solar continuum filter. Would the smaller apo do better in white light solar. In theory the extra aperture if the st120 would help it quite a lot.

Would a 100mm apo do better than my 127mm maksutov on doubles, lunar, etc. Again the extra aperture of the Mak is going to help it.

One 100mm apo costs more than my st120 and mc127 maksutov combined. I'd be interested in hearing any comments.

In my opinion a 100mm ED doublet would have the edge over an ST120 for white light solar observing with a wedge. I use my Lunt wedge with my Vixen 102mm ED and Tak FC 100 and the results are really good.

On double stars I think it would be a close run thing but personally I feel that good ED doublet refractors have provided the most satisfying views of double stars of any scope types that I have used. 

On lunar observing, again it would be a close run thing between a good ED 100mm doublet and a 127mm mak-cassegrain.

 

[Paz]

6 hours ago, John said:

In my opinion a 100mm ED doublet would have the edge over an ST120 for white light solar observing with a wedge. I use my Lunt wedge with my Vixen 102mm ED and Tak FC 100 and the results are really good.

On double stars I think it would be a close run thing but personally I feel that good ED doublet refractors have provided the most satisfying views of double stars of any scope types that I have used. 

On lunar observing, again it would be a close run thing between a good ED 100mm doublet and a 127mm mak-cassegrain.

 

Thanks that is helpful. I was thinking that I find it easier to see how I could replace the st120 and not so easy to see the maksutov going.

My idea has been to maybe replace the 4 smaller scopes I have (from 60mm to 127mm) with just a travel apo and a 4 inch apo so simplifying my kit.

If I can cover more bases with less scopes that would be good.

And besides, I think it has probably gone into the category of being an itch that has to be scratched at some point having noticed that smallish apos are a very common scope in the arsenal of the more experienced observers who still enjoy the hobby after many years doing it.

[Stu]

A good 4" apo is just such a useable and enjoyable scope which does most things well. White light solar with a wedge can be amazing when skies are steady. Double stars are beautiful and clean to view, I prefer the views over the slightly fuzzy stars you tend to get with a mak. You may lose a little resolution for lunar and a bit of reach for deep sky eg clusters would open up a little better in the mak perhaps. I've tried a few maks and keep coming back to my 4".

[nightfisher]

In white light solar i dont think you will see much difference between a 4" apo and the ST120, but the ST should have a slight edge on widefield, I would choose the 127 Maksutov for doubles and Luna

[joe aguiar]

I had a bad 5 in sw mak so as long the mak is excellent made.if it's the mass produced one maybe apo.

Once u use 6 inch  or bigger mak cooldown takes to long.

I think for moon and doubles its probably very close but images still cleaner in apo, but if portability is number 1 concern then stick with mak

Joejaguar 

[Ben the Ignorant]

Not sure about the 100mm apo vs 127mm mak thing but the large achro with a steep f/5 would be bettered by many well-corrected scopes of a sligthly smaller diameter. I would sell the achro to a beginner. Don't forget the 115mm apo diameter, on paper it's in-between the 100mm apo and the 127mm mak but it outperforms both without weighing much more than the 100mm.

[celestron8g8]

IMPO , a true APO  wins over your two scopes . However if funds are there the bigger the better if you could afford it . True APOs’ can take high power much better than any achro can and probably the mak too without degrade . However with true APOs’ to get the best view you need good EPs’ Televues for example . However the best you can afford is your choices . Example in the USA  , Stellarvue make their own EPs’ to help match up their scopes . They can give great views . Also a factor is if you image an APO can give you excellent images and colors . Good luck on your choice of scopes tho ! 

[mikeDnight]

The 4" apo will take higher powers than the Mak while maintaining a sharper star image, and so may prove to have the advantage in double star observing despite its smaller aperture. Again, when it comes to lunar and planetary, its sharpness will not be beaten by the Mak, with the apo sailing along at 300-400X on some targets, while the Mak would struggle to keep up. It stands to reason then that the advantage of a good apo on both stellar and lunar and planetary, then that would also translate when it comes to solar observing.Having said that, the 127mm Maksutov is a remarkably good scope, which in my view is probably the best out of the SW Mak range. The 127 is also a great portable scope. Whether you'd use the Mak much after buying an apo only time would tell.

[Rob Sellent]

@Paz: with reference to a 2 scope combo, from my own experience, I've found the most pleasure using the largest refractor I can comfortably afford, mount and use most often, twinned with the largest Dobsonian I can comfortably afford and use most often. In my own case, this happy medium is a 4" frac and a 10" dob.

From use of a TeleVue 76, a Vixen Fl-102s and a Mak 127, I feel the 127 is a compact, easy to mount scope giving nice, colour free views on a very sensible budget. In terms of performance/£ ratio, the Mak 127 is a fine telescope, costing much the same as a single premium eyepiece, for example.

Nevertheless, I don't feel it's a fair comparison comparing such a scope to a decent apo. If there is any deficit in the apos' light gathering capacity this is more than made up for through the apo's  superior contrast, sharpness, colour correction and quality of the visual image. I feel this visual definition is significantly superior - as is the cost - with the apo and this depends chiefly on the better quality of the optical system.

[rwilkey]

On 12/10/2019 at 01:34, John said:

In my opinion a 100mm ED doublet would have the edge over an ST120 for white light solar observing with a wedge. I use my Lunt wedge with my Vixen 102mm ED and Tak FC 100 and the results are really good.

On double stars I think it would be a close run thing but personally I feel that good ED doublet refractors have provided the most satisfying views of double stars of any scope types that I have used. 

On lunar observing, again it would be a close run thing between a good ED 100mm doublet and a 127mm mak-cassegrain.

Hi Paz,

I agree entirely with John's suggestion, I find my ED100 is a good 'all-rounder', if there is ever such a thing, great for planets and doubles and also solar.  The only thing I found was that I had to up my game in eyepieces to get the most out of the opportunities that a semi apo offers, and to be honest, I have never looked back.  Whether it would beat your combo I have no idea as I have not used the scopes you refer to, but it would give them a bl**** good run for the money.