DOB Goto or NEQ-5 Goto mount for astrophotography?

[gouroun]

Ok so ive decided either to buy a skywatcher 8" skyliner DOB or a skywatcher 200/1000 NEQ-5.When i want to upgrade my kit for astrophotography ill go either for the Skywatcher 8" DOB goto upgrade kit or Skywatcher NEQ-5 pro syncscan goto upgrade kit.Both of those investments cost the same money overall.

The question is which is best for astrophotography?The goto 8" DOB or the NEQ-5 syncscan?I like both telescopes for starters and ill upgrade them for sure in the distant future.

Thanks in advance,

Kiriakos

[JamesM]

An equatorial mount is the way to go for imaging as the axis of the mount head can be inclined to mimic the path of the stars as they move across the sky. It is this 'right ascension' (RA) movement known as 'tracking' that is the key to obtaining sharp focused stars that show no trailing. Now an alt/azimuth mount like that used by the proposed dobsonian or as found with fork mounted heads (used for schmidt cassegrains) track this curve across the sky using very small steps which is fine for observing but will produce poor images as these movements will be recorded in the final image. The way round this is to tilt or wedge the mount so that it resembles an equatorial mount or GEM mount as it is sometimes abbreviated. I think it is highly unlikely that you will be able to wedge the dobsonian mount and so the only imaging available to you with that set up will be with a webcam on either the planets or the moon but not deep sky objects because they need significantly more accurate tracking.

One other consideration is that if you don't have an observatory and you are going to have to set up the imaging 'rig' each time, polar aligning the mount to produce precise tracking will be a bit of a hit and miss affair. To that end many imagers use a device known as an auto guider which focuses on a nearby star to the object being imaged and which in turn adjust the mount's motors to ensure this star is held within its central cross hairs, thus improving the accuracy of the tracking for longer exposures. Now the HEQ5 facilitate this useful bit of kit by providing a port that will allow the motors to be adjusted, I don't believe the dobsonian mount has this capability. What I am trying to get at here is not that you should get all this kit up front but that if you choose the mount carefully (the mount is where the imaging starts) you can future proof what you spend because as your interest and competence grows, you have a mount that will keep pace.

Hope that helps.

James

[studio1one]

has to be the Equatorial mount for photography.

[gouroun]

thanks for the info guys!

do the goto syncscan NEQ-5 kit has auto tracking?

[studio1one]

yes it does.