Dilemma

[CHRlS]

Hi,

I currently own 2 telescopes, a skywatcher 130p heritage and a skywatcher st80. I use the former as my visual scope, from now on it's going to be for lunar and double stars. The only downside is it is a flex tube, allowing light in through the mid section. I keep making shrouds but they don't last. I also prefer a rack and pinion focuser compared to the helical focuser that the heritage is supplied with. The latter is what I use for e.a.a. The only downside I have found is it's too small for visual but perfect for e.a.a. Unfortunately I broke the dob base so I use a skywatcher az gti with both scopes. I'm looking to buy a new mount and tripod, this time with slo mo controls. I would then have a goto and a manual mount. The price of the mount and tripod is £259. For an extra £66 it would come with the same scope as my heritage but not having a helical focuser or a flextube construction. For an extra £130  it would come with an st102, a bit bigger than my st80 but not sure if it would compete with the 130mm reflector. Finally, for an extra £239 it would come with a skymax 127. This one seems to be calling out to me but my observing seems to be spur of the moment.  The only problem with the skymax that is stopping me buying it is the cool down time. I've never used this type of scope before so I have nothing to compare it with, unlike the other two.

In my situation which one would be the best thing to go for?

Thanks.

 

[RobertI]

If it’s lunar and doubles, I would think the Skymax 127 would give the nicest results, but understand that cool down might be an issue if you do short spur of the moment observing. Can you store the scope outside in a shed or garage to keep it closer to ambient temperature? 

[NGC 1502]

If it were my choice-

Skymax 127 for Lunar/Planetary and keep the ST80 for a wider view.  Those 2 scopes nicely complement each other.

Cooldown for the 127 should not be long with the suggestion already mentioned. 
 

Option 2.  Have another try at making a shield for the H 130, and live with the helical focuser. Many have fixed the focuser with PTFE (plumber’s) tape.

Ed.

[SwiMatt]

As a proud owned or a Mak 127, I never noticed excessive cool down times. I was also scared about it before I bought it, but it has not been an issue so far.

My typical observing routine is to walk 10-15 minutes to my observation spot with the Mak in a backpack, set up, and start right away on brighter objects until dark adaptation kicks in. In my experience, by the time I'm dark adapted, the Mak is ready to go. Also the few times I observe from my balcony (taking the scope directly from my apartment outside) I didn't notice problems. Also, I'm a noob, and I suspect that more experienced people might have more fine tuned experiences about this...

[davidc135]

Although there are dissenting voices the majority of experienced observers who have wrapped their Maks in insulating reflectix claim very positive results. But it sounds that it would be barely needed. Still, for pennies, why not try it.

David

[bosun21]

Maks definitely require cool down time to get the best from them. My SW 150 needs at least 1 - 1 1/2 hours if taken from the house directly to outside before it's ready to use. Of course I could use it before this but the heat in the tube is seen as a shimmering image. I also previously owned a 127 which could be ready in about 45 minutes give or take. Once cooled the images are clear and crisp.

[Zermelo]

I agree with the above. My 127 will usually be OK in around half an hour. Obviously, it depends on the difference in inside and outside temperatures on the day, and perhaps how fast the external temperature is falling. If I think I might be observing later, I just sit the Mak outside the back door to cool, and leave the setting up until I'm sure.

[CHRlS]

4 hours ago, RobertI said:

If it’s lunar and doubles, I would think the Skymax 127 would give the nicest results, but understand that cool down might be an issue if you do short spur of the moment observing. Can you store the scope outside in a shed or garage to keep it closer to ambient temperature? 

I would keep the scope in the shed so I guess that would help.

[CHRlS]

4 hours ago, NGC 1502 said:

If it were my choice-

Skymax 127 for Lunar/Planetary and keep the ST80 for a wider view.  Those 2 scopes nicely complement each other.

Cooldown for the 127 should not be long with the suggestion already mentioned. 
 

Option 2.  Have another try at making a shield for the H 130, and live with the helical focuser. Many have fixed the focuser with PTFE (plumber’s) tape.

Ed.

I might have to have a look at a new shroud even if I get the skymax, I would then have a different types of  telescopes rather than two of the same.

[CHRlS]

4 hours ago, SwiMatt said:

As a proud owned or a Mak 127, I never noticed excessive cool down times. I was also scared about it before I bought it, but it has not been an issue so far.

My typical observing routine is to walk 10-15 minutes to my observation spot with the Mak in a backpack, set up, and start right away on brighter objects until dark adaptation kicks in. In my experience, by the time I'm dark adapted, the Mak is ready to go. Also the few times I observe from my balcony (taking the scope directly from my apartment outside) I didn't notice problems. Also, I'm a noob, and I suspect that more experienced people might have more fine tuned experiences about this...

I guess I probably wouldn't notice the difference either as I still class myself as a noob. If you can use it straight away on your balcony, I guess taking mine out from an unheated shed would be even better?

[CHRlS]

3 hours ago, davidc135 said:

Although there are dissenting voices the majority of experienced observers who have wrapped their Maks in insulating reflectix claim very positive results. But it sounds that it would be barely needed. Still, for pennies, why not try it.

David

For the cost, maybe every little helps 

[CHRlS]

3 hours ago, bosun21 said:

Maks definitely require cool down time to get the best from them. My SW 150 needs at least 1 - 1 1/2 hours if taken from the house directly to outside before it's ready to use. Of course I could use it before this but the heat in the tube is seen as a shimmering image. I also previously owned a 127 which could be ready in about 45 minutes give or take. Once cooled the images are crisp

Perhaps I could cut that time in half by storing it in the shed rather than a house.

[CHRlS]

2 hours ago, Zermelo said:

I agree with the above. My 127 will usually be OK in around half an hour. Obviously, it depends on the difference in inside and outside temperatures on the day, and perhaps how fast the external temperature is falling. If I think I might be observing later, I just sit the Mak outside the back door to cool, and leave the setting up until I'm sure.

I like the idea of leaving just the scope outside just in case.

[Carbon Brush]

My experience has been that cool down time does matter - but how much?
If you were to carry your scope/mount/tripod in one lump from from a 23C room to a 0C outside and expect to immediately count Jupiters bands, GRS, etc, yes it matters.

Storing the scope in a cooler room, or a shed, or garage, or in a (not recently driven) car will help.

In practice we tend to carry things out separately and assemble outside. It takes longer, eating into cool down time.
Then of course we tend to look at an 'easy' target, low magnification, to check the scope is all OK, finder aligned, and the sky is as clear as we thought.
Finally we get around to viewing something at high magnification.
The quickest setup is of course a manual dob. Anything with goto has the levelling and alignment time.

HTH, David.
 

[bosun21]

When I take my 150 Maksutov outside from indoors and set it up in daylight I looked through it at low magnification to check my finder alignment it was like looking through water. I returned 1 hour later and although greatly diminished the shimmer was still detectable. Another 30 minutes and it was perfect. As I use this primarily for planetary imaging it’s crucial to cooldown fully. The 127 is about half this time and significantly less again if stored in a shed or outhouse.

[CHRlS]

19 minutes ago, Carbon Brush said:

My experience has been that cool down time does matter - but how much?
If you were to carry your scope/mount/tripod in one lump from from a 23C room to a 0C outside and expect to immediately count Jupiters bands, GRS, etc, yes it matters.

Storing the scope in a cooler room, or a shed, or garage, or in a (not recently driven) car will help.

In practice we tend to carry things out separately and assemble outside. It takes longer, eating into cool down time.
Then of course we tend to look at an 'easy' target, low magnification, to check the scope is all OK, finder aligned, and the sky is as clear as we thought.
Finally we get around to viewing something at high magnification.
The quickest setup is of course a manual dob. Anything with goto has the levelling and alignment time.

HTH, David.
 

I guess I've been blessed with the heritage, being able to just grab it out the shed and being able to start using it straight away, especially with it being a flex tube. 

[davidc135]

1 hour ago, CHRlS said:

For the cost, maybe every little helps 

Many, again experienced observers, feel that Reflectix made a revolutionary difference to their observing with larger Maks i.e being able to observe virtually straight away when previously they needed an hour or so of cooling.

It works, non intuitively, by slowing the rate of heat loss from the OTA.

Certainly with my 8'' sct wrapped in two layers, it seems ready to go from the off although it would be worthwhile comparing 2 scts of similar quality, with and without the covering, to be sure of the effect.

David

[Louis D]

8 hours ago, CHRlS said:

The only downside is it is a flex tube, allowing light in through the mid section. I keep making shrouds but they don't last. I also prefer a rack and pinion focuser compared to the helical focuser that the heritage is supplied with.

For all of these reasons, and to be able to use 2" eyepieces and a GSO coma corrector, I went with a GSO 6" f/5 Newtonian Reflector Telescope with LB Focuser.  The focuser works fine once the tension is adjusted just right.  The central obstruction is a bit large for visual use, but the scope is intended for imaging.  It's pretty light for its aperture and steel tube.  The images through it have been fantastic.  The mirror seems very well figured.  I use it on a manual alt-az mount with no issues.

[Zermelo]

6 hours ago, CHRlS said:

I like the idea of leaving just the scope outside just in case.

... as it is doing right now ...