Question about Esatto 3"

PrimaLuceLab ESATTO 3" robotic focuser PrimaLuceLab SESTO SENSO 2 Focuser
5 replies•140 views
Jerry Gerber avatar
Jerry Gerber avatar
Hello!

I am replacing the stock focuser that came with the Askar 130 PHQ,  this scope is at a remote site so I rely on tech support from the people at the site.

Does anyone have any direct experience with the Esatto focusers?   I am not sure which adapters to get with it so that it will be able to come to focus.  Backfocus shouldn't be an issue as the Askar is a quadruplet refractor with the field flattener built into the scope.   I'm assuming the 3" is the right size as the image circle of the Askar is 60mm and the aperture of the 3" Esatto is 76mm. 

I am currently using the Sesto Senso 2 focuser and it works well, but the stock focuser on the scope isn't handling the somewhat harsh (dust) environment very well.    I am open to the possibility of another focuser but what I like about the Esatto is that the new focuser and the EAF will be the same device, rather than replacing the focuser and then adding a separate EAF. 

Thanks for commenting!

Jerry
Respectful Engaging
Miguel Noppe avatar
Miguel Noppe avatar
You should try and find out what thread connection the focuser has and then see if there's an adaptor available from Primalucelab.
Once you're sure there's an adaptor you need to now what the preferred focal plane is measured from the end of the tube where the focuser screws on.

Then you just combine the length of the necessary pieces including the Esatto's half racked out length (so you got some play around the focal plane) until you get to what you need.

For example for my Esprit 120 with reducer (not the same as with flattener !) I needed :

Adaptor 3" Esatto for Skywatcher Esprit 120 & 150 + 65mm Extension tube + Esatto 3" + adaptor M81 - M68 (for my reducer)

CS,
Miguel
Helpful
Jerry Gerber avatar
Jerry Gerber avatar
Miguel Noppe:
You should try and find out what thread connection the focuser has and then see if there's an adaptor available from Primalucelab.
Once you're sure there's an adaptor you need to now what the preferred focal plane is measured from the end of the tube where the focuser screws on.

Then you just combine the length of the necessary pieces including the Esatto's half racked out length (so you got some play around the focal plane) until you get to what you need.

For example for my Esprit 120 with reducer (not the same as with flattener !) I needed :

Adaptor 3" Esatto for Skywatcher Esprit 120 & 150 + 65mm Extension tube + Esatto 3" + adaptor M81 - M68 (for my reducer)

CS,
Miguel

Thanks Miguel, that's helpful!
Jerry
Dunk avatar
Dunk avatar
PLL have a couple of videos of the ESatto on an FSQ85 - not the same I know, but they do mention all the adapters etc. 

My advice would be to try hard to use as few PLL adapters as possible - they are super expensive (I speak from experience ;-) )
Jerry Gerber avatar
Jerry Gerber avatar
Dunk:
PLL have a couple of videos of the ESatto on an FSQ85 - not the same I know, but they do mention all the adapters etc. 

My advice would be to try hard to use as few PLL adapters as possible - they are super expensive (I speak from experience ;-) )

Yeah, I saw how ridiculously expensive they are, probably can find adapters that can do the job for 5-10 times less money...
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