Flattener Reducer for Skywatcher Evostar 150ED Deluxe

[bluesilver]

Hi,  I have a bit of trouble trying to find out what the correct flattener / reducer to use for the Skywatcher Evostar 150ED Deluxe

The Deluxe version is pretty much the same as the standard version but with the upgrade focuser. ( black focuser not the standard white one )

I am lead to believe that the focuser on the Deluxe version is the focuser from the Skywatcher Esprit 150

So i am looking to mount a ZWO ASI107MC camera to this scopes focuser.

I think i need a flattener / reducer to make this happen.

Now i see that Skywatcher make the standard ED 150 Refractor 0.85x Focal Reducer / Corrector, but i think this is for the standard model with the standard white focuser.

I think i need the one for the Esprit 150,  they call it Esprit 150 Refractor 0.77X Focal Reducer / Flattener.

But i have just seen on a site here in Australia one called Evostar ED 150 0.77x Focal Reducer / Flattener.

Now they both look the same but the specs are slightly different 

Esprit specs are:  F/D = 5.4   F= 809mm  Image Circle = 36mm

Evostar specs are: F/D = 6.2  F = 925mm  Image Circle = 34mm

 

I can't get hold of the Shop here and they still haven't replied to emails so was hoping i might be able to possibly get some advice from here?

I haven't seen this Evostar ED 150 0.77x Focal Reducer / Flattener listed anywhere else,  i have done a bit of searching and nothing has come up which is a bit odd,  can't even see any of them on Skywatchers site either.

 

So basically just trying to find out what is the correct Reducer / Flattener to use with this scope and if the camera will mount directly onto it,  or is there another way to mount the camera?

 

Any advice would be greatly appreciated.

Thanks.

 

 

 

 

[Budgie1]

Skywatcher make three 150mm refractors:

Evostar 150 - the basic version with an achromatic lens element and a standard focuser.

Evostar 150 ED DS-Pro - double the price of the basic with an apochromatic lens element and a Crayford duel speed focuser.

Esprit 150 - 3x the price of the DS Pro with a triple apochromatic lens and a Crayford duel speed focuser.

If you have one of Evostar models then the reducer/flattener for the Esprit won't be optically matched to it. The reducer/flattener for the Evostar is designed for the DS-Pro version and is optically matched to it, so if you have the achromatic version the reducer/flattener for the DS-Pro may make a difference to the field of view by flattening it but I think you'll still get other artefacts like blue halo around stars due to the lens type in the scope. 

I'm sure others more experience with these can provide more info but I would definitely check with the shop before buying anything. 

You can also get a T2 adaptor to connect a DSLR, these screw on to the focuser tube to replace the diagonal but you may need spacers to obtain the correct back-spacing for the camera. I didn't need spacers for my DSLR to Evostar 100 ED DS-Pro but I don't know about the 150.  

[bluesilver]

Thanks for the reply,  appreciated.

I have the Evostar 150 ED DS-Pro which has the  apochromatic lens element and a Crayford duel speed focuser

When you say connecting the DSLR to the focuser,  Mine came with that adaptor included,  it just screws onto the focuser and the DSLR then just connects to this.

I just then wind out the focuser to get a correct focus.

Just trying to work out how to connect this ASI107MC to the focuser.

It would be great if i could find out more about this Evostar ED 150 0.77x Focal Reducer / Flattener,  sounds like the right one,  but just waiting to here back.

 

 

[Budgie1]

On my ED100 DS-Pro I use the 2" adaptor which came with the scope and fixes into the collar that screws onto the focuser tube. I think this has the M48 thread on the end and my ASI294 MC Pro camera screws on to that using the 11mm, 16.5mm and 21mm spacers supplied with the camera.

I have the 0.85 reducer/flattener and that screws to the same scope attachment. The camera then screws to the back of the reducer/flattener using the same three spacers to give the correct back-focus. This is all with the standard white Crayford focuser. I have since upgraded to the black version with the built-in rotator and got a 2" adaptor which screws on the front of the reducer/flattener so it will slide into the focuser. 

I hadn't seen the 0.77 reducer/flattener from Skywatcher before but did find them on some U.S. websites. They are more expensive than the 0.85 but are made for the DX focuser and bring you down f6.2 with your ED150. So looks like that's the one you need.  

[bluesilver]

Thanks again for the reply, very much appreciated.

Is there by any chance you have a photo of this setup?

I am just trying to work out a picture this 2" adaptor.

My scope doesn't have this 2" adaptor and also didn't come with a diagonal either.

I have got a 2" GSO diagonal that i use when i want to use eyepieces,  but even after unscrewing this i can't see how to fix the ASI017MC to the scope.

My scope came with what they call a 2" T-adaptor with 48mm thread and a Canon T-Ring 48mm

http://www.astroanarchy.com.au/telescopes/Skywatcher_ED150_Deluxe.html

But still no lock getting them to attach to the camera.

My camera as i am guessing is the same as most ZWO asi cameras,  has a female thread on the camera,  the two spacers have a male and female thread,  so that once they are screwed onto the camera you are left with a female thread on the spaces.

That then means that i need a male thread at the focuser end to allow me to screw the spacers onto.

The camera come with two spacers,  T2 21mm extender, T2 48mm 16.5mm extender and a M42 - M48 adaptor.

http://www.astroanarchy.com.au/astrophotography/ZWO_071MC_Pro.html

I think i need to connect the camera and spacers to the end of the 2" T adaptor with 48mm thread,   if i take this 2" T-adaptor of i am left with something like a 78mm thread ( 3"),  way to big far any of the fittings that came with the camera.

Any advice or ideas would be greatly appreciated.

 

 

[bluesilver]

Hi,  Just had a reply from another source and it appears to work,  not sure if it is correct or not.

But this long 2" T adaptor with 48mm thread that came with the scope,  screwed onto the end of this T-adaptor is an attachment for a Canon DSLR ( i forgot to mention this bit sorry )

I have found that if you unscrew this Canon ring adaptor of the end of this long 2" T adaptor with 48mm thread,  you then have this Canon ring adaptor.

On the Canon ring adaptor there is 3 small flat head screws,  undo these and and the ring adaptor comes apart in 3 pieces, a Canon adaptor, ring with a 48mm thread and a adaptor that is something like 3" to 48mm.

You set aside the first two pieces, and re screw this 3" to 48mm adaptor back onto the long 2" T adaptor with 48mm thread.

Then the ZWO asi017mc spaces screw straight onto it.

So long story short,  if i have this all setup and installed correctly,  the ZWO asi017mc camera now screws directly onto this long 2" T adaptor with the the two spacers attached.

Basiaccly just taking of the DSLR camera and reinstalling the asi017mc in its place.

Dose this all sound correct?

 

 

[Budgie1]

That sounds about right.

I took photos of my setup with the ASI294MC on the Evostar 100ED DS-Pro and with the original focuser that came with the scope.

The 2" adaptor that came with the scope looks like this:

But I think the upgraded Crayford focuser I fitted is the same or similar to the one on your DX. In which case I had to get the push-in adaptor I linked too in my previous post and can be seen attached to the front of the 0.85 reducer/flattener in the second photo below.

With the ASI294MC it only has 6.5mm from the front face of the camera body to the sensor, so it's supplied with an 11mm spacer which to bring it to 17.5mm, then it has the 16.5mm & 21mm spacers added to give the 55mm back-spacing from the reducer/flattener lens.

In the case of the ASI071 that you have, the sensor to front face of the camera body is 17.5mm, so it's only supplied with the 16.5mm & 21mm spacers.

Edited July 9, 2021 by Budgie1
Spelling

[bluesilver]

Thanks heaps for the photos,  yes looks like a slightly different setup to hat i have.

This is what i have now ended up with, Just wasn't too sure if i had it right,  but looking at you setup it is similar

I haven't got a reducer or flattener in mine.

Pretty much just remove the DSLR and install the asi017mc

Dose this setup look right to you?  first time using one of these cameras as i have just been using DSLR before.

Just have to wait for a clear night to see how it all works.

 

[Budgie1]

If the setup worked with the DSLR then it should be okay with the ASI071. The only thing to watch is that you can get focus. If the focus tube is all the way in and you can't quite reach focus then remove one of the spacers from the camera and try again. 

You may find that the images will have slightly blurred or elongated stars around the edges,  this can only be corrected with a field flattener or reducer/flattener. But you should still be able to get some good images without these.  

Have fun on the next clear night!

[bluesilver]

Thanks,  if all else fails i will have to look at that slide in adaptor you put a link to.

I was a tad concerned with that long T-adaptor that is used for the DSLR.

Below is what it looks like without the long T-adaptor.