SPC900NC Finderguider

[WireD64]

Im in the process of building a finderguider out of my Skywatcher 9x50, i have a spc900nc with 1.25 adapter ready to fit.

My questions are:-

Is the LX mod necessary to use this as a guider? will it still work well enough without being lx modded. 

Should I fit a UV/IR filter?  I do not plan on using the webcam for anything but guiding so what filter if any is best?

Rich

[astromerlin]

Hi Rich, No filter is needed other than to keep dust out of the sensor but if it is always kept in the finder why bother, I dont.

You might find finding stars a problem without lx modding it, some targets are ok with a bright star in the fov ie the veil nebula. I use mine at around 2 sec exposure and never had a problem getting a star in the fov of the finder.

[WireD64]

Thanks for the input John. Is yours LX modded then?

[astromerlin]

Hi Rich, Yes I modded it myself. The spc900 is quite easy to mod, the first one I did was the Philips Vesta and really needed micro surgery.

http://www.home.zonnet.nl/m.m.j.meijer/D_I_Y/spc900nc.htm

[WireD64]

Thanks, i might be biting off more than i can chew with that circuitry mod.

Just out of interest now, what is the amp-off mod used for?

[astromerlin]

The amp-off mod is used to lower the amplifier voltage when in long exposure, images taken with very long exposures say 10secs and longer get a bright patch on the image. You wont need the amp-off mod for just a guider.

[WireD64]

Great, thanks for the info.

I shall find someone I know to tackle the lx mod for me.

[iksobarg]

Hello, this technique is new to me. wired64. You want to make an autoguider out of a 9x50 finderscope and a webcam?? How effective is this?

Looking this up...

It must truly be an expensive way to autoguiding.

[WireD64]

Hello, this technique is new to me. wired64. You want to make an autoguider out of a 9x50 finderscope and a webcam?? How effective is this?

Looking this up...

It must truly be an expensive way to autoguiding.

I have chose this option as it is actually a much cheaper solution for me, I already have the 9x50 finder scope so no cost there, and the SPC900NC cost me £50 so it should only cost me a few pounds extra getting it attached, I will make my own adapter to fit this to the finderscope although these can be bought for around £35.

I will be guiding through PHD, ive seen this done with a Logitech quickcam 4000 pro to good result. (See Quatermass' EQ5 dual axis project) So thought the SPC900NC should be a little clearer.

[iksobarg]

Hi,

I meant inexpensive.

Ooops,

John

[WireD64]

Hi,

I meant inexpensive.

Ooops,

John

Ah thats makes all the difference now. 

If your thinking of going this route let me know how you get on

[wuthton]

I used an unmodded Philips for years as a guider to great effect.

I would recommend upgrading the camera when funds allow though. The bigger chips on the likes of the QHY5-II give a much greater selection of guide stars.

[WireD64]

I used an unmodded Philips for years as a guider to great effect.

I would recommend upgrading the camera when funds allow though. The bigger chips on the likes of the QHY5-II give a much greater selection of guide stars.

Thats great to hear it works unmodded, I shall give it a test first then see how I get on without the LX mod

[iksobarg]

I'm all in for methods that are cost-minded. As I have yet to select a mount I'm definitely interested in learning more about how to do this.

I've still not looked the topic/instructions up but will. Share any links you may have?

[WireD64]

This is pretty much what got me thinking about it, http://astrocasto.blogspot.co.uk/2012/02/how-to-set-up-guiding-system-for-your.html

My plan is to do exactly the same but with the SPC900NC rather than the Logitech 4000