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3 minutes ago, Laurin Dave said:

You need to enter 206 mm as the focal length and 3.75 um  as the pixel size...  

Dave

Sorry, well spotted, Dave.  Fat fingers, this should of course be 3.75.

Edited by RayD
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Is that in the Minimum Star HFD value? 

 

ah nvm I've found it now, on the camera tab. 3.75 was already set as the pixel size. But 50mm was set as the focal length.

Edited by smr

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Just now, smr said:

Is that in the Minimum Star HFD value? 

No, that's in your camera pixel size.  Make a new profile using the wizard and when the questions are asked, you can have it try to detect your pixel size, but if it can't then enter 3.75 in your camera pixel size, and 206mm in focal length.

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They're the numbers you need to enter into the equipment profile for guidescope focal length and camera pixel size.. 

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So with it being set to a totally inaccurate focal length how would that affect the guiding? I don't understand the science behind it :)

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I think that having 50 mm as the focal length will result in corrections 4 times too big 

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with completely wrong values, everything will incorrectly calculate so the corrections will be wrong and the guider will go crazy

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3 minutes ago, smr said:

So with it being set to a totally inaccurate focal length how would that affect the guiding? I don't understand the science behind it :)

It would make it look like your images 😉

The software calculates how far your mount is moving from the guide star by calculating the distance from the 2 measurements above.  If they are out then it will have no idea what is happening as the corrective pulses will be wrong.

Edited by RayD
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Thanks guys. I think that was the problem then. It still needs further refinement and more precise calibrating, I did run through the guiding assistant again and applied the settings but it said something about not being able to guide in dec properly. 

Looks better now though

guide.thumb.jpg.11ec44f5e3858f9ccff3c7913eb9dea5.jpg

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Looks good to me.

Are your stars round? If so, enjoy the images and don't worry too much about PHD. 

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Certainly does... maybe  try balancing your mount so that the rising side and the camera end are slightly heavy as that may help  (it keeps all the gears engaged) .. but most of all enjoy the clear skies tomorrow and hope it goes well 

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26 minutes ago, Star101 said:

Looks good to me.

Are your stars round? If so, enjoy the images and don't worry too much about PHD. 

Yes round stars at 240 second exposures :) Very happy with that. 

21 minutes ago, Laurin Dave said:

Certainly does... maybe  try balancing your mount so that the rising side and the camera end are slightly heavy as that may help  (it keeps all the gears engaged) .. but most of all enjoy the clear skies tomorrow and hope it goes well 

Thanks. I actually did tonight for the first time, made it slightly east heavy.

Thank you very much for all your help and replies guys. I'll read the articles on guiding tomorrow on the first page. 

Finally got autoguiding. Fantastic.

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Nice one,i had the same nightmare,and when it happens it very frustrating,glad you got it sorted.

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Great stuff, looks good.  

The issue with the dec guiding is because it is seeing backlash there when doing the calibration (mapping what it expects to see against what it is seeing.  You don't need to worry, this happens often.

When and if you start tinkering (we all love a tinker) then you can run your PA out slightly and guide in one direction only in dec.  However, with 240 sec subs with good stars, I'd leave it like that and enjoy the very rare clear skies :thumbright:

Edited by RayD

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Looks much better now. Reminds me of when I started guiding! 1.25" RMS error isn't bad. It's about half your image scale of 2.22 arc seconds per pixel assuming your using what your signature says. That's about what you should be aiming for. I wouldn't get too hung up on the graph. You will get some good nights and some bad nights. Nature of the game! A good polar alignment at the start will make things much easier.

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Finally set about imaging bodes galaxy. Quite small in my fov so I will have to crop in, guiding seems good. 4 minute exposures.

 

bodes.thumb.jpg.6dc3206e4a10d0438c73d8d68ecdafd6.jpg

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5 minutes ago, mikeyj1 said:

it's better than my guiding now 😉

! :)  What do the numbers mean ?

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they show the average (rms) and peak guiding errors in pixels and arc seconds.   So long as your rms error is around half your scopes image scale (both in arc sec per pixel) all will be fine and your stars will be nice and round.  Not sure what camera you are using but with your scope focal length I'd expect it to be fine 

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7 minutes ago, Laurin Dave said:

they show the average (rms) and peak guiding errors in pixels and arc seconds.   So long as your rms error is around half your scopes image scale (both in arc sec per pixel) all will be fine and your stars will be nice and round.  Not sure what camera you are using but with your scope focal length I'd expect it to be fine 

Thanks, I'm using my Canon80D.

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I would start over with a new Equipment Profile.

This will take you through the settings step by step, including pixel size and  focal length.

Also your Star Profile is less than optimum.

The top of the profile should never be flat, probably over exposure as you are using 3 seconds, 1 to 2 seconds is more normal.

Then start guiding with the preset settings.

Michael 

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8 minutes ago, michael8554 said:

I would start over with a new Equipment Profile.

This will take you through the settings step by step, including pixel size and  focal length.

Also your Star Profile is less than optimum.

The top of the profile should never be flat, probably over exposure as you are using 3 seconds, 1 to 2 seconds is more normal.

Then start guiding with the preset settings.

Michael 

Are you referring to the image a few posts up ?

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Hi Guys

In same situation, and want to venture into AP

Want to purchase a tablet first to download PHD2 to

Also looking at zwo120mm or the zwo290mmand Orion 50mm micro focuser 

Silly question

I also do presentation for scout/guide groups, primarily Joey's and Cub's scout movement,  and Brownies guide movement

Will I be able to project images through the zwo, on the screen of the tablets, for kids whom are physically impaired, and restricted to wheelchair

I also in Southern Hemisphere, and polar aligning is totally different down there, as do not have equivalent to Polar Star to align to

South Celestial Pole is roughly 4 times the length of the Southern Cross (CRUX), and big black hole    

John

Edited by cletrac1922

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@cletrac1922

I am not sure a tablet will work for imaging as many of the equipments you will need require a USB port.

Carole 

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17 hours ago, smr said:

Are you referring to the image a few posts up ?

Looks like a much better session has occurred since.

Michael 

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