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Help & guidance required on Astrophotography


Pankaj

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Hi. I have been doing visual observations on a dobson mount and non-tracking equatorial mounts for years now. Lately (about 6 months back), I had purchased a 10" Skywatcher (f 4.7) on a Dobson mount. About a month back I had also purchased a Canon EOS 1200D. Connected the camera on Prime Focus with the 10" dobson, and aimed at the moon with a Skywatcher 2x Barlow between the camera & the telescope and shot a 2 minute video. The results were amazing (at least to me the results looked very good).

Now come the topic where help is required....

(A) Can I use the same technique to vediograph Jupiter and Saturn ? Is video better for these two planets or still photography ?

(B) Can I use the same technique to videograph Binary stars like Alberio and Almaak ? Or should I take still photos.

© Is this technique also useful to capture M31....video or still ? which will be better ?

Request expert comments and personal experiences please.

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A) Yeah, video for Jupiter and Saturn. It really helps with a tracking mount but you can if you're really good push the scope in order to capture enough frames.

B) It'll probably be extremely hard since the starlight is a very narrow band of light, and the atmosphere makes it move. Longer exposures with a tracking mount is probably better, plus you get more context by seeing the surrounding stars. You could however try with high ISO and short exposure times, you might get lucky if the star is bright enough...

C) M31 is faint compared. You need to be using equatorial, tracking mount for this.

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You might get Jupiter and Saturn but the number of poor frames will be high, and there may not be that many good frames to stack into a good image.

Doubt that you sill get binary stars and DSO's are almost certainly going to fail.

Not sure how you will get Jupiter and Saturn as you cannot be at the scope tracking either, the camera will be where the eyepiece usually sits.

As said you have a visual scope that is not particularily suited to imaging.

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Not sure how you will get Jupiter and Saturn as you cannot be at the scope tracking either, the camera will be where the eyepiece usually sits.

Can in theory be done with Live View or live video output on a computer, but its going to be hard and even more super hard once you start stacking the magnification...

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Dear All. Thanks for the valued comments. I guess I'll have to go in for a EQ Motorized/GOTO mount. Which mount is suitable for the skywatcher 10" solid tube. Its a F 4.7, so I think, it'll do a reasonably good job in imaging. Please suggest suitable equatorial motorized mounts.

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Hi again

The 10" solid tube is not suited for imaging. Way too large, heavy and bulky for a normal mount to handle. Even the NEQ-6 will struggle with it. Unless you start looking at the really expensive mounts... but those are not good for beginning.

When you read about the load capacities of different mounts, you should always count that in half when imaging. A NEQ-6 will handle 20kg or so for visual, but it's only recommended to load 10kg for imaging. You honestly need a mount that can carry the telescope + extras and not struggle. If you overload the equipment you will have to throw images away. You can always get some results, but the goal is to get consistent results, not having to throw away 75% of the images due to vibration and backlash in the mount.

I would suggest getting a refractor like 80ED and a HEQ-6 or NEQ-6 mount to start out with astrophotography and keep your excellent dobson for visual.

However the first piece of advice is always, read Steve Richards book "Making Every Photon Count" before you buy anyhing else. It's an excellent guide and will probably save you a lot of money by avoiding costly mistakes. http://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

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Hi again

The 10" solid tube is not suited for imaging. Way too large, heavy and bulky for a normal mount to handle. Even the NEQ-6 will struggle with it. Unless you start looking at the really expensive mounts... but those are not good for beginning.

When you read about the load capacities of different mounts, you should always count that in half when imaging. A NEQ-6 will handle 20kg or so for visual, but it's only recommended to load 10kg for imaging. You honestly need a mount that can carry the telescope + extras and not struggle. If you overload the equipment you will have to throw images away. You can always get some results, but the goal is to get consistent results, not having to throw away 75% of the images due to vibration and backlash in the mount.

I would suggest getting a refractor like 80ED and a HEQ-6 or NEQ-6 mount to start out with astrophotography and keep your excellent dobson for visual.

However the first piece of advice is always, read Steve Richards book "Making Every Photon Count" before you buy anyhing else. It's an excellent guide and will probably save you a lot of money by avoiding costly mistakes. http://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

Thanks a ton Carl. This was a very valuable piece of information. Really appreciate it. Will start exploring a refractor with NEQ6 mount, for imaging purpose. Is there any other refractor and mount you would suggest ? How is the Orion Sirius mount ? Can that be used with 80ED ?

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Thanks a ton Carl. This was a very valuable piece of information. Really appreciate it. Will start exploring a refractor with NEQ6 mount, for imaging purpose. Is there any other refractor and mount you would suggest ? How is the Orion Sirius mount ? Can that be used with 80ED ?

Sorry, mean to say HEQ-5 and NEQ-6. The Celestron equalivents are Advanced VX and CGEM. Can't speak about any other mounts since I have no experience or know any people who use them.

THere are more expensive APO-refractors than the 80ED, also the 80ED is a type that comes from several manufacturers.

The PDS-range newtonians are good, using the 150 myself, but they need a coma corrector to take a flat field image, much the same as refractors need flatteners. It's a jungle of equipment out there, so be sure to read the book I recommended first, before buying ANYTHING else.

You can also look at the MN-190 if you want a good quality astrograph with high aperture, decent cost.

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An astronomy shop in India has suggested me to buy an Orion 80mm Shorttube OTA with Celestron Omni CG4 mount with dual axis motor drive for tracking. This this combination sturdy and reliable for astro-photography of DSOs ? Please suggest.

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Hi again.

The Orion 80mm has cheap lens setup (does not have ED glass) and will give chromatic aberration, hence not suited for photography. It's more suited as a guide-telescope or for simple visual observations.

The CG4 is weak and will struggle to give consistent results compared to a HEQ-5 or better mounts.

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Whilst there are short falls with the ST80 there are some nice images members have managed with it, my take as a novice stargazer if budget is limited spend on the best mount and compromise on the scope as that can be replaced later and the ST80 will always have uses as a grab and go or guide scope or keep saving.

A wobbly mount is a wobbly mount regardless how expensive the telescope on top.

http://stargazerslounge.com/topic/227259-short-andromeda-with-st80/?fromsearch=1

http://stargazerslounge.com/topic/228389-st80-40-minute-north-american-nebula/?fromsearch=1

http://stargazerslounge.com/topic/228722-noisy-cacoon-st80-dslr/?fromsearch=1

http://stargazerslounge.com/topic/228395-st80-veil-nebula/?fromsearch=1

Have you been able to read the book often mentioned? Making every photon count.

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Whilst there are short falls with the ST80 there are some nice images members have managed with it, my take as a novice stargazer if budget is limited spend on the best mount and compromise on the scope as that can be replaced later and the ST80 will always have uses as a grab and go or guide scope or keep saving.

A wobbly mount is a wobbly mount regardless how expensive the telescope on top.

http://stargazerslounge.com/topic/227259-short-andromeda-with-st80/?fromsearch=1

http://stargazerslounge.com/topic/228389-st80-40-minute-north-american-nebula/?fromsearch=1

http://stargazerslounge.com/topic/228722-noisy-cacoon-st80-dslr/?fromsearch=1

http://stargazerslounge.com/topic/228395-st80-veil-nebula/?fromsearch=1

Have you been able to read the book often mentioned? Making every photon count.

Hi. Was not able to get hold of the book. Its not available in the market in New Delhi. Besides, its not possible to order in US dollars fro India, as the issues of customs would arise. I have a cousin residing in Seattle, US. He'll be visiting india in Dec 2014. I have asked him to carry this book along. You certainly have a point when you suggested to invest in the mount. In your opinion, which mount should I go for considering that I will never go beyond using a 120mm APO refractor as its payload. GOTO can be avoided, as I am pretty conversant with the sky charts. please show me way forward. I am totally novice in selecting EQ motor driven mounts, and the dealers in India seem to be only interested in clearing their dead stocks. 

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