Astrophotography With Meade Etx 90 Maksutov Cassegrain

[Lebster31]

Hello, I am new to this site but hoping to learn a lot from people on here. I recently purchased a Meade ETX 90 Maksutov Cassegrain telescope. I was hoping to take astrophotography with this telescope, but failed to find any reliable sources on what camera to buy. I was wondering if anyone knew any decent cameras that would fit on my ETX 90. Keep in mind I wouldn't like to spend more than 500 dollars on the camera alone. Any answers will be greatly appreciated, thank you!

[Owmuchonomy]

Hello and welcome to SGL. I believe your scope is f/13.5 and sits on an Alt/Az mount. If so, these present significant hurdles to doing any astrophotography. The equipment will restrict you to short exposures of bright objects only, just the Moon to be honest. If you wish to consider astrophotography seriously then the general advice will be get a faster scope and an Equatorial mount. Therefore my advice would be not to waste your money on trying to get a camera to suit.

Edited January 16, 2016 by Owmuchonomy

[JonC]

Depending on the mount it can be used in equatorial mode, some of the tripod combos come with an EQ wedge, my 105 is setup in EQ mode its an option on the controller on the 125.

I have only used my ETC105 for visual, but it does have a port on the back to allow camera attachment. A better start might be to piggy back a DSLR on top of the scope and use camera lenses. Something like an 1100d, T adapter and a 300mm prime would be well under your budget, it would also give the option to attach the camera to the back of the scope, although weight is a problem. But it will get you going cheaply. 

Edited January 16, 2016 by JonC

[carastro]

You'll be able to take the Moon and Planets OK with your telescope and mount, you will need a camera suited to video photography, such as a webcam or I think the IMGOH camera which is a bit more expensive will also do some Deep sky stuff. 

http://www.modernastronomy.com/shop/cameras/cooled-ccd/qhy-cooled-ccd-cameras/qhy-imgoh-mono/

The trouble with an Alt Az mount is the way it tracks which is not suitable for long exposure (which is what is needed for DS imaging), also your telescope focal ratio is too high for long exposure, it will take a lot longer to capture the required data, and of course with your mount this is not going to work.

If you got the IMGOH you might get away with doing some short long exposures i.e. not too long, (15 secs or something) and get away with it on bright targets, but you'll get field rotation when you come to stack them, so you will be limited.

If you do have a wedge on your tripod as suggested above, this might improve the situation.  

HTH

Carole 

Edited January 16, 2016 by carastro

[NSS_Ian]

Hi Lebster

If I am not mistaken the New ETX is on a wedge mount and you can set it for EQ tracking. I have yet to hear how well it works though. Did you have any success ?

 

[michaelmorris]

I owned a ETX 90 for years.  The optics are really nice and it's well suited to imaging the Moon, Sun and brighter planets.  Unfortunately, the mount is a bit pants.  IMHO the only useful imaging of DSOs that can be achieved with an ETX 90 is mounting it on an equatorial wedge and using it for piggy-backing a DSLR with a wide field lens.

[michael8554]

Yes NSS_Ian, the latest ETX's seem to have a tripod with a tilt head, to convert the Alt/Az Mount to EQ.

Hi Lebstar, for years I did planetary and solar imaging with an EQ tripod-mounted ETX 125, onto a tiny webcam chip.

Quite challenging to keep the object on the chip, should be easier with the slightly bigger 1/3" chips on modern budget planetary cameras, and $500 should get an even bigger one.

The RA drive on the ETX's has too much slop for long exposures of DSO's in my experience of the 125.

Michael

[Dov1962]

Hi Lebster   I am going to use a nikon D40  (a lightweight  dslr) on my 125 ETX on the polar mount   along with the t mount and  Meade back cell adapter..   dont buy a heavy camera  like the nikon or canon top ranges they are cast metal frames   the weight has been known to fracture the rear port of the etx with the meade adapter attached.  you could  fabricate and attach a metal bar to the bottom of the 90  supporting the dslr to the rear cell.. that has worked in the past.

[Red meteor]

Hi Lester.

I own an etx90ra and like you wanted to do some imaging. The RA model is very old and has no computer. I managed to get some lunar and planetary shots with a webcam and at the time was pleased with my pics of Mars and Jupiter. It was difficult to find the target though. I attempted the Pleiades at one point and got something but soon gave up

 The DSLR was just too heavy and restricted where you can point it.

To be positive I would suggest trying a camera like the zwo asi120. A lot less costly than your budget and really useful camera as a guider if you progress to dso's later. It will be good for taking lunar and planetary videos and can do longer exposure as well.  Also works well for capturing fireballs.

DSO's really need autoguiding but give it a try on something bright like the Pleiades. 

Good luck and don't give up too easily.

Graham