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Hi,currently owned 70mm refractor, want to upgrade and many suggested me to get 6" dobsonian.

The only 6" dob i can find in my country is GSO 150mm/1200mm dob (https://www.opticaluniversescientificinstrument.com/products/gso-6-dobsonian-telescope), is this brand and specs ok?

My main targets is planet and moon, maybe some star, i wonder is it hard to imaging planets? ill be using ccd eyepiece connected to laptop. 

I live in malaysia city area, very less likely i will bring the scope to darker area because its pretty far from my home,and the scope quite big, so its dobsonian suitable for minor light population? 

I heard that that dobsonian can affected by weather and cooling the scope be a big issue? 

hope expert can give some advice. thanks

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The 150 Dob is a very nice scope and would suit you well for observing  the planets and Moon. However it is not ideal for imaging as you have no tracking other than manual. It is possible to image the Moon because it is bright and requires short exposure times. 

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If you're handy, you can make yourself an equatorial platform to put under the Dob to get decent tracking for planetary imaging for an hour at a time.

As far as seeing, if you're near the coast, you may have excellent seeing owing to laminar flow off the ocean.  Cool down (warm up?) time should be minimal in the tropics.  It's all about the differential between the storage temperature and the observing temperature.  If you're in Canada in the winter, that could be as much as 90 degrees or more.  I've got to think it's much less in Malaysia.

Don't forget to budget for eyepieces and collimation tools as well.


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The 152mm Dob is a very good option for visual work. However as noted, it really doesn't work for any imaging. The reason being that it is a completely manual telescope.  Also as noted if you are handy you can build a motorized equatorial platform or you can buy one. They are quite expensive though. Another option would be to buy the Skywatcher AZ-GTi, the EQ wedge for it, and use your 70mm refractor for imaging. This will be a less expensive option than buying a platform if you cannot or do not want to make it. 

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Hello Mr GuGuzai

Dobsonians are a great choice, usually size 8 , or 203mm with 1200mm focal lenght is the sweet spot. (https://www.opticaluniversescientificinstrument.com/products/gso-8-deluxe-dobsonian-telescope



it depends on your budget at the end. all should do well for planets. I see planets fine in my 130mm and 250mm mirror telescopes. more detail in the latter.

Big mirrors does get affected by weather, change of temperature from warm to cold or vise versa (if telescope is stored inside then you bring it outside for example), it will require allowing the mirror to settle to surrounding temperature in the observing site. some use fans, but around 30 mins of waiting should be fine.

as for imaging, manual dobsonians and any manual Altazimuth mounts will make tracking obejcts hard, as you need long exposures to get good imaging. however some experienced astrophotographers manage to get ok images with dobs.


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GSO dobs are great scopes, and a 6" will show you much more than a 70 mm refractor. An 8" even more. Light pollution is not so much a problem for lunar or plantary observing, but you need steady air to see details. While you can experiment with imaging the brightest objects, a dob really isn't suitable for astrophotography, as other have said. But for visual use, a dob gives you the best bang for the buck. Good luck!

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