Just acquired an SX Lodestar, need a bit of advice please

[chrisshillito]

 A guide camera is not there to take nice pictures... I suppose I should try using dark subtracted guide frames but then what propblem would I be trying to solve?

But for 'sub pixel guiding' the quality of guiding is dependent on the autoguider being presented with a image upon which it can accurately calculate the centroid of the guide star. The better exposed the guide image, and the more dynamic range present, the more accurate the centroid results will be. I doubt guiding would ever suffer by using dark subtracted frames but, under some conditions it might just improve a tad.

Chris.

[triley4]

Thanks for your response - My main reason for getting it was Lodestar live as I struggle at the eye piece now cos of my health - I'd be taking crude images with it also - It would act as an alternative guide when I image with my dslr only.

Would hot pix hinder me in Lodestar live ? I expected at lot less with a chip rated class A.

[Astroboffin]

Thanks for your response - My main reason for getting it was Lodestar live as I struggle at the eye piece now cos of my health - I'd be taking crude images with it also - It would act as an alternative guide when I image with my dslr only.

Would hot pix hinder me in Lodestar live ? I expected at lot less with a chip rated class A.

Hi,

I have emailed Terry at SX and he has told me that because these cameras are not cooled there will always be hot pixels and that taking darks will sort it out, I, like you expected a lot less in a class 1 chip, but I think our expectations were a little too high.

Yours looks about the same as mine.

You do have to re take the darks each time in PHD 1 as they match the duration of the guide exposure, and that does get rid of 95% of them! also when testing indoors you will get a few more because of the warm, it will be better when using outside in the colder air.

One other thing I have noticed, is that if you use the Ascom driver instead of the native SX one, the image seems a lot better to me, much less noisier and less hot pixels, but not sure why, although I have read in a few forums that this Ascom drive is much better.

There is also an option with the Ascom driver to bin the camera, which again reduces the hot pixels and makes it a lot more sensitive, not that this camera need that, but over all I much prefer using the Ascom driver.

Try it and see. There is a link on the SX site to it.

Hope that helps a bit

AB

[triley4]

Hi,

I have emailed Terry at SX and he has told me that because these cameras are not cooled there will always be hot pixels and that taking darks will sort it out, I, like you expected a lot less in a class 1 chip, but I think our expectations were a little too high.

Yours looks about the same as mine.

You do have to re take the darks each time in PHD 1 as they match the duration of the guide exposure, and that does get rid of 95% of them! also when testing indoors you will get a few more because of the warm, it will be better when using outside in the colder air.

One other thing I have noticed, is that if you use the Ascom driver instead of the native SX one, the image seems a lot better to me, much less noisier and less hot pixels, but not sure why, although I have read in a few forums that this Ascom drive is much better.

There is also an option with the Ascom driver to bin the camera, which again reduces the hot pixels and makes it a lot more sensitive, not that this camera need that, but over all I much prefer using the Ascom driver.

Try it and see. There is a link on the SX site to it.

Hope that helps a bit

AB

It sure does thanks - Ref LS live Do you think the pix will effect viewing? I aprieciate dark frames in guiding will negate them but when I first saw the star field of hot pix with the cap on I thought that it would make distinqushing a star from a hot pix when merely observing was going to be an exspensive nightmare.

[Astroboffin]

It sure does thanks - Ref LS live Do you think the pix will effect viewing? I aprieciate dark frames in guiding will negate them but when I first saw the star field of hot pix with the cap on I thought that it would make distinqushing a star from a hot pix when merely observing was going to be an exspensive nightmare.

I think when you get outside with the camera, and set it up,on your scope pointing at a nice dark sky, you will barely notice the hot pixels, try it out and see, but I think you will be pleasently surprised with the difference, against using the camera inside with the cap on.

Let me know haw you get on

Regards

AB

[triley4]

Sure will - thanks

[JR1987]

I think when you get outside with the camera, and set it up,on your scope pointing at a nice dark sky, you will barely notice the hot pixels, try it out and see, but I think you will be pleasently surprised with the difference, against using the camera inside with the cap on.

Let me know haw you get on

Regards

AB

[JR1987]

I gotta agree there, once I took mine outside, hot pixels were not an issue.

Also, even if they were, stars are much bolder and easily distinguishable compared to any hot pixels you may encounter

[Thalestris24]

Hi

That's cos PHD autostretches the screen display

Louise

[triley4]

Hi All - First light at long last! An hour and an half set up time cos I am rusty but so chuffed with the results. What a remarkable piece of kit through an ED 80 on a humble EQ2-3. Never anticipated what a joy it was to use. As foretold the hot pixels where not an issue. Didn't bother with dark frames this time round but by my reckoning I only have a few when the temp is down. The first image is un-stacked and the second is stacked - got the horizontal banding some have reported on the stacked image but I don't know if this a cause for concern or not?  Thanks for the advice and I can't wait to get out again. Bring on the obys this summer so I can just point and shoot at leisure.

[triley4]

Stacked