TAL 100RS or Mak 127 for lunar/planetary grab-n-go

[DevonSkies]

I currently have a nice 10" Dobsonian complemented with a ST102 f/5 achromat for grab-and-go sessions. Whilst the Dob is a great all-rounder, the ST102 shows its weaknesses during Lunar and Planetary viewing (mainly limited contrast due to CA). So I'm considering getting a third scope dedicated to lunar/planetary.

Currently I'm considering the TAL 100RS and the Skymax 127 Mak. Very different beasts, but essentially both long focal length scopes with 4-5" apertures.

Which do people think would be the better choice? I'm aware there will be some CA on the TAL, but how troublesome is it? What I'm looking for is crisp, satisfying views of the moon and (as far as seeing allows) planets.

Other suggestions also welcome!

Ed

[Chris]

My guess is that the Mak will have crisper views, and the Tal will have more charm

[brantuk]

I have both the SW Mak 127 and Tal100RS and I have to say there's not a lot to choose between them for clarity and crispness of views. And I find them both a complete charm sat side by side on my Skytee2. The Mak has a longer focal length and focuses slightly further on a clear, transparent night - so you can get a little more detail on planets - conversely I find the Tal is a little wider  on the deep sky. But it's really not such a big difference to discern one from the other.

I would say get them both lol - but I think your criteria to choose only one will be more practical or aesthetic, rather than technical. Others will differ but hope that helps.

[Roy Challen]

I haven't used a Mak, but given the choices you list I don't think there will be a significant difference. The Mak has more aperture, so the image will be a bit brighter, but is obstructed so will lose some contrast. It will need longer to cool down, but it's short so doesn't need a heavy duty mount.

The Tal will have some CA, but only a bit. It does need a reasonably good mount - AZ4 or EQ5 size as a minimum.

Tough choice really.

I got a Tal, and don't for one minute regret it.

HTH

[Steve Ward]

Not a lot between them , but neither will produce views that come anywhere close to matching the 10" ... 

[Moonshane]

Out of the two, I'd go for the Tal but personally, I'd try and get a 100mm ED. My reasons:

• Cooldown almost instant with the frac
• Field is 50% more in the frac so wider field observing is possible when preferred
• If you wanted to get into white light solar, the frac would be great with a herschel wedge
• I'd imagine the views will be very similar at the same magnification

[DevonSkies]

Thanks for the comments so far. My heart says Tal, but my head says Mak due to its more compact size!

Good point about the 100ED, Moonshane. I already have the ST102 for wide field views, but I could consider the 100ED as a future upgrade path.

[Moonshane]

On reason I suggested the ED was that being used to the CA free views of newts, I found CA rather irritating and especially on planetary views, e.g. Jupiter.

I have never found it so on ED scopes. Obviously the Mak would be CA free I'd expect too but never really used one.

[happy-kat]

For me the mak then you have one of each and it is compact.

[spaceboy]

I'd get the Mak. Reasons: I don't see much point in getting another 4" scope despite the longer focal length. The Mak will take longer to cool and it will be a dew magnet but they offer completely false colour free, pin sharp stars across the field of view and with the longer focal length and aperture it will allow for more magnification when the seeing allows.

[DevonSkies]

I'd get the Mak. Reasons: I don't see much point in getting another 4" scope despite the longer focal length. The Mak will take longer to cool and it will be a dew magnet but they offer completely false colour free, pin sharp stars across the field of view and with the longer focal length and aperture it will allow for more magnification when the seeing allows.

Thanks, that makes sense. The Mak should complement the ST102 with its colour-free views. Further in the future I could consider upgrading the frac to an ED if I feel the need.

[Steve Ward]

I'd try and get to look through one or both before you buy either , the views will be disappointing when compared to the 250PX , I know this from experience having had the same dob as my first scope .

I get great views now through the Mak180Pro that I use for Lunar/Planetary observing but the extra resolution that the 10" gave was noticable.

[Peter Drew]

I can't see either of them beating a 10" Dob for the Moon and planets.

[laudropb]

I'd go for the Mak, mainly because it is more compact for a grab and go.

[nightfisher]

If you plan to keep the ST102 then get the Mak, but remember the Mak wont take 2" ep`s (they do make a 2" version but not available here)

[DevonSkies]

I can't see either of them beating a 10" Dob for the Moon and planets.

I'm not expecting it to better the Dob, I just want a small scope for grab and go that performs well on planets/lunar. The Dob is too heavy to haul out just for a quick look at the moon.

[DevonSkies]

If you plan to keep the ST102 then get the Mak, but remember the Mak wont take 2" ep`s (they do make a 2" version but not available here)

Shouldn't be a problem. I don't intend to use it for wide fields (I have the ST102 for that).

[nightfisher]

I see you have the Vixen porta, this would work with the mak but the finder scope might end up at 8 o clock

[RT65CB-SWL]

Mak's are good for terrestrial viewing too!

[DevonSkies]

I see you have the Vixen porta, this would work with the mak but the finder scope might end up at 8 o clock

Yes, you're right. Actually I thought I might splash the extra £100 for the version on the Synscan AZ goto mount. That version has the dovetail on the side instead of the bottom. Then I would have the option of using it on the goto mount for tracking or the Porta II for quick views. And I can also use the ST102 on the goto mount as a bonus!