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unable to get focus (real newbie)


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 please  could somebody advise me where I'm going wrong>

 equipment:   EQ6 R-PRO Mount, William Optics 123 Apo, Camera ZWO ASIO71 MC, ASi pro, EFW.

  My first two outings, with the following equipment have proved very  disappointing from the start. I've been unable to obtain  almost any focus, no matter how I place the camera I however cannot obtain any focus or I get a multitude of green dots?  Please see photo.  the only way I've managed to obtain any form of focus is to put the camera on video using the ASI, and pushing the gains up to maximum, if I use live, or preview mode and unable to focus at all, I have tried using the spaces provided can someone point me in the right direction please.

a38fdddb-0057-43b6-81cc-883ee3dbe8cd.JPG

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Can you share a picture of the setup? Give or take you need around 55mm from the back of the focuser/flattener to the plane of the camera sensor. It may well need to be tweaked beyond that but if it's not in that ballpark you'll probably struggle.

Once that's correct we can move to the next thing if there is one.

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18 minutes ago, Thomas martin said:

William Optics 123 Apo

Do you have a reducer/flattener attached to your 123?

The recommended WO R/F for this scope is apparently discontinued but I am sure alternatives must be available.

As @scotty38 says some photos of your equipment setup would be helpful. :)

 

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17 minutes ago, Thomas martin said:

Hi Adreneline> No reducer/flattner attached

A nominal figure of 55mm assumes you have a R/F fitted - really not sure what it might be without one.

Might be worth investigating getting one (alternative WO or third-party) - it will be of overall benefit to your imaging as it will change the setup from f6 to f4.8 (0.8x reducer) as well as improving star shapes.

HTH

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1 hour ago, Thomas martin said:

Please see photo.

Just noticed the screen shot from your ASIair looks like you are using a Bahtinov Mask.

Silly question but were you running the Auto Focus feature on the ASIair with a BM fitted? Hopefully not :) 

Do one or the other - I use a BM to get close to focus - sometimes I use AF but then nearly always recheck with (and adjust/fine tune) with a BM.

You can also use the Detect Stars (accessed from the Tool icon) to give you a quantitative figure for your focus. DS is also for keeping a check on focus drift during an imaging session - just don't become obsessed by it!! ;)

 

Edited by Adreneline
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Hi Adreneline, Please feel free to have a chuckle I've just found a William optics focal reducer 0.8 F6 Apo

 it was in a  cut out in the case, next silly question what do I do with it, is it a case of just attaching it to the camera?

sorry as I said I am a real newbie at this, and regarding  the BM  yes you are right I think at one point I had that on, as well as trying to use the autofocus, but to be honest by that point I was just getting so frustrated I forgot to take it off.  thanks for all your advice and guidance very very much appreciated

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26 minutes ago, Thomas martin said:

what do I do with it, is it a case of just attaching it to the camera?

My experience says you fit the r/f to the focuser and attach the camera to the r/f with whatever spacers are required to achieve a spacing of 55mm (nominally)

I did come across this website and he makes the following comment re. spacing with the WO R/F : "Note that for the FLT-123, the middle back-focus setting of 76mm on the reducer produced the flattest field (the back focus is adjustable from 66mm to 86mm)." Of course he may have a different R/F compared to the one you found in the box! I think this site is translated from Japanese so it's not always that clear, however, there are lots of useful photos that will show you how it all goes together. 

HTH

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53 minutes ago, scotty38 said:

okey dokey as @Adreneline says you can disregard the 55mm comment then.... 🙂

Not at all :) Most r/f are 55mm but as with everything in AP some are different - or have different threads - or holes where you don't want them that don't match with anything other single piece of equipment you own. It's all part of an evil plan to get you to spend money. Perish the thought you should ever reach the stage where you have everything sorted. It's a minefield - tread carefully!

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Many thanks for this, gave me a lot of info about the scope, from reading  the information, mine  is one of the four that has a Strehl 0f 988

however not much use when you can't even get past first base>>>😂

thanks for finding the info

Tom.

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29 minutes ago, Adreneline said:

Not at all :) Most r/f are 55mm but as with everything in AP some are different - or have different threads - or holes where you don't want them that don't match with anything other single piece of equipment you own. It's all part of an evil plan to get you to spend money. Perish the thought you should ever reach the stage where you have everything sorted. It's a minefield - tread carefully!

I meant disregard in the fact that he did not have a reducer etc and hence shouldn't need to worry about the 55mm but as seen there is one 🙂

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