How to shoot planets with a 150/750 Newton?

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sylvestrerato
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Joined: Mon Apr 01, 2013 8:32 am
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How to shoot planets with a 150/750 Newton?

Post by sylvestrerato »

Hi,

I have a Newton telescope and I usually try to shoot deep sky objects but I'd like to try planets. I wondered what was the best cheap method to do that? Do I need a barlow for instance?

Thank you for your help.

Cheers

Brian
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Re: How to shoot planets with a 150/750 Newton?

Post by Brian »

Hi there.

With planets you'll need to be working at focal lengths of somewhere between 3 and 5 metres in order to get an image scale on-chip which will show good detail. So yes, I think a barlow (x3 to x5) will be required. At your telescope's native focus you will still be able to image Jupiter and the Galilean moons around it, but the planet's disk will be small and probably just a burned-out white dot.

From the information you give, it seems that you already have a camera that you use for deepsky imaging, so initially I would test it for planetary. Maybe it will save you having to buy another camera for planetary work.

Which camera are you using at present?

regards,
Brian
52.3N 0.6W
Wellingborough UK.

254mm LX90 on Superwedge, WO ZS66SD, Helios 102mm f5 on EQ1, Hunter 11x80, Pentax 10x50
ASI120MC Toucam Pros 740k/840k/900nc mono, Pentax K110D
Ro-Ro roof shed

sylvestrerato
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Joined: Mon Apr 01, 2013 8:32 am
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Re: How to shoot planets with a 150/750 Newton?

Post by sylvestrerato »

Thanks Brian.

I'm using an old Canon 300D but I also have a Toucam Webcam.

Brian
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Re: How to shoot planets with a 150/750 Newton?

Post by Brian »

Toucam 740,840 or 900 all make good planetary cams :D
Brian
52.3N 0.6W
Wellingborough UK.

254mm LX90 on Superwedge, WO ZS66SD, Helios 102mm f5 on EQ1, Hunter 11x80, Pentax 10x50
ASI120MC Toucam Pros 740k/840k/900nc mono, Pentax K110D
Ro-Ro roof shed

sylvestrerato
Posts: 5
Joined: Mon Apr 01, 2013 8:32 am
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Re: How to shoot planets with a 150/750 Newton?

Post by sylvestrerato »

What's best with my telescope and Toucam? Barlow 3x or 5x do you think?

Brian
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Joined: Fri Dec 03, 2004 9:58 pm
Location: Wellingborough
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Re: How to shoot planets with a 150/750 Newton?

Post by Brian »

In my experience, it will depend to some extent on your mounting. As focal lengths increase the field of view on the CCD sensor gets smaller and tracking, together with ability to make fine adjustments in pointing, becomes an important consideration. It's your decision , but I'd suggest getting a x3 barlow lens. This will give you a bout 2 metres focal length, and if you can increase the distance between the barlow and the CCD (extension tube, diagonal) then you can get more than x3 with a good lens,

regards,
Brian
52.3N 0.6W
Wellingborough UK.

254mm LX90 on Superwedge, WO ZS66SD, Helios 102mm f5 on EQ1, Hunter 11x80, Pentax 10x50
ASI120MC Toucam Pros 740k/840k/900nc mono, Pentax K110D
Ro-Ro roof shed

PRBenson
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Re: How to shoot planets with a 150/750 Newton?

Post by PRBenson »

I know this discussion is going back a while but I was in the same position a couple of years back.

My solution was to purchase a Skywatcher Skymax 180 maksutov through UK Astro Buy & Sell since it had a basic focal length 3x that of the Newt. This means less reliance on the use of barlows. In my experience it is always best to try and minimise the amount of glass between the camera and your target. I then used the Newt just for lunar imaging and deep sky.

When imaging planets the disk size is always going to be tiny so the small chip of a webcam is definitely the way to go. I started off using a TouCAM and got some excellent results. I then upgraded to a DMK 21AU04 as the mono CCD and higher frame rate gave me much sharper results.
TMB152;Tak TOA150/FSQ106ED;Lunt LS152T/LS60THa;Orion 16" Dobsonian;Meade 14" LX200GPS
Canon 5DmkIII;DMK 21AU618;ASI 120M
AP 1200GTO;EQ6 Pro

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