MOTORS

[kev 102 42]

GOOD MORNING GANG would a Single-Axis D.C. Motor Drive for EQ3-2 be any good for imaging or would it after be a dual moter drive thank you .........kev[/]

[barkis]

I doubt it very much Kev. It would not be accurate enough on it's own to keep the target object steady for imaging.

Unless you have some means of guiding, ie, a seperate guidescope with a reticule, and a means to speed up, or slow down the drive motor, you will have a difficult time doing exposures of reasonable duration.

Of course, if the said motor is a stepper motor, they are controllable to a degree of accuracy, but you will still need a seperate guide system.

Ron.

[kev 102 42]

what is a seperate guide system and stepper motor thanks barkis.........kev

[John]

I'm not an imager but I think it might be ok for planetary and lunar imaging - I've managed some basic stuff with undriven alt-azimuth mounts so I'm sure an equatorial driven even on just one axis would be an improvement on that !.

You would need to ensure that your mount was polar aligned as carefully as possible.

For long exposure, deep sky imaging I'm sure you would need the sort of setup that Ron is referring to.

John

[Ant]

I've used an EQ3 with single axis (RA drive) and managed prime focus shots of between 20 and 30 seconds.

It will be a good start to imaging... but you'll need to be realistic to how high you can go with that.

You'll get some nice results though, but you'll not be able to go over the 30 second limit without some luck in polar alignment - even then I wouldn't expect to get anything over 40 maybe 45 seconds before trailing shows...

Ant

[kev 102 42]

i only want to image m42 and some stars just the easy stuff, as im not well enough to really get into imaging..........kev any info will be appreciated thank you

[jgs001]

Kev, I've no tried imaging with any form of eq mount, but I'm getting results with my AltAz mount. I'd suggest, as long as the costs aren't prohibitive, then go for it and see how you get on. At 15 to 30 seconds there's a lot of targets you can image, at 45 seconds I was able to get the bubble nebula, ok I took a huge number of frames.

[kev 102 42]

thhanks ant and john thats what i want hear :hello1: it can be done .......kev

[jgs001]

Kev, the key is to understand that you will face, hit and probably bounce off the limits of what the gear is capable of. Accept that, identify what you can achieve by trial and error and choose targets accordingly.

[Psychobilly]

Excellent Advice there for you Kev and like John's comments

[MartinB]

Of course you can do it Kevin! There's no point in having the dec driven except for fine tuning position independently of the slo mo controls or if you are doing guided imaging. If you can motorise your RA you are up and running for deep sky imaging. You will be plonking yourself right at the bottom of the learning curve which is a great place to be. I still remember the thrill of my first DSOs.

Try to get a good polar alignment - doing this by eye isn't really good enough. A polar scope helps but drift aligning is best. It takes a bit of practice but is pretty quick once you get the hang of it.

Avoid long focal length scopes since they amplify tracking errors. A short focal length refractor is ideal.

Expose for as long before the stars start to trail too badly. Slighly oval stars are ok. The longer the exposure the less noise you will have in your images. With a reasonalbe polar alignment 60 secs should be ok. You will find that sometimes you get more trailing than others because of where the mount is on its PE curve.

Here is a link to some of my early unguided images using a very simple ATik 2HS - a modded web cam.

http://www.astropixels.co.uk/Atik_images.htm#Atik_images

[kev 102 42]

Thanks. all i want to do is have ago at imaging as cheap as possible, cos im ill most of the time and when im ok get out with the scope and camera and have a play ,i could go out and get all the gear and only use it about 10 times................kev

[kev 102 42]

thank you Martin great advice ,and billy i will be watching you like a hawk i got a bit of a buzz going i want to start imaging NOW ............kev

[steppenwolf]

Kev, I think you should give it a try despite the limitations. If you concentrate on the brighter objects (you mention M42 which is a good choice as is the beautiful open cluster M45) to allow shorter exposures you will achieve some reasonable results but I would agree that your exposures will be limited to a maximum of 30 - 45 seconds although you could certainly try longer, say up to a minute and just discard the images that show star trailing.

For reference, the enclosed image of M45 was taken with an EQ3 mount and single RA motor, a DSLR and an 80mm achromat. I took 2 exposures of 70 seconds each and combined them in Registax. As you can see, the stars have just started to trail but if I had taken lots more subframes, I believe that this would have made a very nice image. The EQ3 is a little more substantial than the EQ2 but the motor-drive is no better!

Give it a try!

[kev 102 42]

hi Steppenwolf if i can take a pic like your m45 i will be well chuffed............kev im going to order the motor from FLO now thank you all.........kev

[kev 102 42]

i also have a very heavy weight to hold my mount rock solid.

[Psychobilly]

Kev,

Which scope are you palnning to image through... As Steve has hinted youd be much better off with a Short focal length refratcor or even usign the camera with a lens piggy backed to started and move on as you start seeing results... Some nice tracked widefield images would be a great confidence booster

Billy....

P.s. Dont watch me because I just fly by the seat of my pants haven't got a clue what i'm doing really just let the technology take care of things.... Haven't even considered drift alignment...

[kev 102 42]

ive got the 102 evostar F=1000mm to long is it?

[Psychobilly]

ive got the 102 evostar F=1000mm to long is it?

Yes and no...

Something around 300-400mmm would be a lot more forgiving... but its not 2000m like an 8" SCT...

Lets hope we get a chance to get out the weekend after next

BIlly...

[steppenwolf]

A 1000mm focal length won't help your cause much I'm afraid as it is relatively long but back to bright objects, short exposures and lots of them! I am assuming that you have a DSLR so don't forget that you can take great wide field images with a camera lens and these wider field of views will allow longer exposures - lots to try once you have a motordrive!

[Psychobilly]

Will Kev need an extension piece to achieve focus with the DSLR? or should he be ok without one... Did you get an EOS - T mount adaptor Kev?

Sure Steve at FLO will make sure you have got everything you need...

[kev 102 42]

T-mount adapter what is that ,i have a camera adapter ,will i need an extension piece?

[kev 102 42]

T-mount adapter what is that ,i have a camera adapter ,will i need an extension piece?

just had a look it comes with a Direct SLR Camera Connection?

[Helen]

I think that means you don't need a t-adapter but if you need a t-adapter I've got one you can long-term borrow!

Helen

[barkis]

Kev, I apologise mate. My post was based on my attempts at imaging from many years ago.

It probably put you off a bit, but of course todays software aids and digital cameras do make it possible to capture images by combining multiple short exposures, and building a good result.

I should have put more thought into my first answer.

Good luck with your imaging.

Ron.