Focusing/Live View Canon 1000D

[Catweazel]

Hi all,

I have a Canon 1000D (unmodified) that I use for AP. I have managed to get a few pics (mainly moon but some Orion Neb) but am having a problem getting focused with other targets. I am using APT with live view mode on the 1000D and a Bahtinov mask on the scope. The problem seems to be that I can't see anything on the live view screen on APT; I know that live view works OK, and I can see the bright star in the viewfinder, but not on the LCD screen or in ATP? I wondered if the 1000D just isn't sensitive enough? Or maybe it's LP? I'm really not sure.

Any help much appreciated as always. CW

[Gina]

Use the maximum ISO for focussing. Find the brightest star in the sky and you should be able to see that in live view.

[Steve Ward]

As above ,

ISO 1600 and Bulb settings.

Pick a bright star and zoom in on it to focus.

I also find that setting the camera to Monochrome when focusing gets rid of the distracting red noise at 1600ISO making the mask pattern easier to tune.

Steve.

[Bizibilder]

Agreed, as above.

[Catweazel]

Thanks for replies.

Pick a bright star and zoom in on it to focus.

When you say zoom in, do you mean use the 5x, 10x function on the camera in live view? Sorry, I'm new to most of this

[Steve Ward]

Sorry for being so vague . .

Yes you can zoom on on the star with APT in Liveview , top right of the main window.

Steve.

[Catweazel]

I got it to work in live view earlier, saw the star @ 10x mag in APT, focused, then by the time I picked a target, the scope was out of focus again. I think that the camera may be too heavy for the Megrez, and is pulling the focusing tube down?

[Bizibilder]

There should be a lock-screw on the focusser to prevent it slipping.

[gkec]

Some very useful advice. I thought it was just me having problems focusing a 1000D!

[Catweazel]

There should be a lock-screw on the focusser to prevent it slipping.

Yes there is a lock screw, but I'm guessing that the focuser tube is a bit loose, as the more vertical the scope is the faster it slips, it's quite difficult to keep an eye on APT, focus and tighten the screw, think I might need an extra pair of hands

[Steve Ward]

Focus on the star , lock the focuser carefully then recheck the diff. pattern .

Focus can shift slightly when locking so you may need to "over-focus" to compensate for this.

I always make the last focus adjustment "outwards" to make sure that any backlash is taken up and the focuser has less chance of minute slippage.

Steve.

I'm using USB controlled motor focuser but principal the same for manual focus.

[Catweazel]

Thanks Steve, will give it a try next time out

[Yoddha]

Yes there is a lock screw, but I'm guessing that the focuser tube is a bit loose, as the more vertical the scope is the faster it slips, it's quite difficult to keep an eye on APT, focus and tighten the screw, think I might need an extra pair of hands

If your focuser is similar to my ZenithStar you would have two screws one for locking and one that controls the tension. With the help of Allen wrench is possible to increase the tension but do not make too tight or the focusing know will not work.