Baader Clicklock focus on a 150 or 250p-ds Newtonian

[mikeyj1]

I was so excited to replace my standard 2" fitting on the Skywatcher with the Baader Click lock:- perfectly centred and grips like a vice.  Only one problem - I cant reach focus with the 1300d now!  A friend (Adyj) fitted one to his 150p-ds and has the same issue - about 5-10mm more inward focus needed.  I guess it may be possible to move the mirror up the tube, but starts getting potentially problematic 

Anyone have another solution, or do i have to send it back?

thanks

Mike

Edited October 20, 2018 by mikeyj1
added photo

[Yearofthegoat]

I looked into this a while ago and wrote to Baader about it. I wanted to do away with the thumbscrews of the focusser drawtube clamp and the 2" and 1.25" eyepiece holders.
 

I didn't get round to doing it until now, so I'll dig out my email from Baader but do you have the S57 going into the original Skywatcher focus tube clamp?

 

[Ricochet]

What size is the thread at the bottom of that adaptor (and hence inside the focuser tube)? There is a clicklock called "M54a Skywatcher/Orion" that may fit, and there is a review on the FLO item page that talks about using it on the 250pds. If it does fit then switching clicklocks will gain you whatever length focal path that adaptor uses up.

[mikeyj1]

Yes it’s the m54 that I bought, the sw Adapter in the photo screws directly into the focus tube, so the click lock replaces that, so it’s true that it fits, but bottoms on  the outside of the focuser when trying to focus with camera, which is fitted with a coma corrector

[mikeyj1]

10 hours ago, Yearofthegoat said:

I looked into this a while ago and wrote to Baader about it. I wanted to do away with the thumbscrews of the focusser drawtube clamp and the 2" and 1.25" eyepiece holders.
 

I didn't get round to doing it until now, so I'll dig out my email from Baader but do you have the S57 going into the original Skywatcher focus tube clamp?

 

would be good to hear what Baader told you.  looking at it again this morning, I think the only two options if i want to use the Baader Click lock are 1. replace the focuser with a low profile version 2. shorten the tube/move the mirror in a bit, which is not going to be easy..  i could potentially take 5mm off the top of the focuser housing, but once again...seems like i may end up causing more problems than i solve!

[mikeyj1]

Ok, i have an update, and wanted to post it for reference to anyone else with the dilema above:

I was able to move the mirror on the existing screws far enough up the tube to get focus with the Canon.  Typically after cleaning or flocking I would wind the screws in fully, and then back them off around two turns to make the collimation.  The gap between the mirror cell and the housing was around 2-3mm and the springs were under good tension, which seemed the best option.  I was able to move the cell about 6mm using this method, giving a focus point clearance on the click lock of around 3mm.  The focus tube still protrudes into the image train considerably, so i may look at shortening that.  However, I changed out the Canon for my Altair GP290c, and the focus point is considerably further out, so wont be able to remove as much as i initially thought.  Here are some pics to explain better:

The pencil line is the original focus point with the std adapter.  This extended position is the GPcam focus point, with the 1.25" adapter fitted ontop.  After moving the mirror, i have 3mm clearance from the clicklock to the housing

Here is the gap now - big enough for a finger to fit in, or perhaps more importantly, light path to enter, so i think i need to cover the back end now.  Note the locking screw (smaller one) is almost at limit of travel.

 

thanks for the replies

Mike

[Yearofthegoat]

That's a great bit of info ?

I dug out my emails, and I must have mis-remembered, as I contacted Baader about the MPCC MkIII and EOS cameras, not the ClickLock, sorry.

A bit OT, but they said the MPCC MkIII should work fine, by the way:

Dear Yearofthegoat,

the MPCC is designed for a distance of 55mm - this has been the T-2-standard since the times of chemical photography. If the sensor is placed in this distance, the MPCC will correct the coma and keep the image quality in the center.

The T-2-standard has been "softened" a bit because there are newer cameras (Micro-Four-Thirds, Astro-CCD-cameras) which can easily be placed in a different distance, because the T-2-thread on their housings is closer to the sensor. I did a quick google-search, most threads I had found concern either Schmidt-Newton-telescopes or CCD-cameras (where you have to take care of the correct distance and can't use standard adapters), or users who use a low-profile T-ring or inserted an off-axis-guider.

The first MPCC was designed long ago for f/4.5, the MPCC III works fine between f/3.5-f/6 (and without less vignetting than a triplett-coma-corrector). If it somehow doesn't work, there is either something strange in your setup or a problem with the shipped unit of the MPCC - in the latter case, it is a warranty-case (then you have to contact your dealer about replacement/repair), in the first case, we'd need to see an image or description of your setup - then we can better judge where the problem may be.

If you want to use an off-axis-guider, you might want to use the RCC coma corrector and the RCC Off Axis Guider.

Best regards,

Alexander Kerste
BAADER PLANETARIUM GMBH

 

Thanks for posting the pics of the ClickLock - it looks like I'll need to go for something else as I really don't fancy messing with the mirror (well done for doing that, though!). It's a shame as I would like to eliminate the thumbscrews.

My 150PDS (and your mate Adyj's I guess) has the same focusser as your 250PDS, so I'm thinking maybe a Hotech SCA T-Adapter, and just use the normal thumbscrew stuff for visual (since it's not as critical an issue).

I've yet to get a coma corrector, so I'll need to check that w.r.t. focus with the Hotech in place.

Edited October 24, 2018 by Yearofthegoat

[mikeyj1]

2 minutes ago, Yearofthegoat said:

I'm assuming that my 150PDS has the same focusser as your 250PDS,

Thanks YOTG

Ady has that scope, so he or I will post about the outcome soon...the difference to the thumbscrews is immediately obvious, i was getting off axis mishapen stars on some images, and now there is no chance or movement at all, so i would recommend that you strive to get rid of them...i will let you know if there are any other issues or benefits.  

[Yearofthegoat]

Thanks - I just popped over to OVL and the focussers have exactly the same specs,  so the outcome should - sadly - be the same unless there's quite some flexibility in the manufacturing!

If the ClickLock, with its 30mm depth, is short by max. 10mm then the Hotech with 19mm depth should -just- be okay.

Might just get one and see. I suppose I could return it if it didn't work out.

[adyj1]

Unfortunately it will take me a few days before I can try this on the 150PDS. I'll post when I get the chance... 

Ady

[Yearofthegoat]

Cheers Ady that would be great.

[adyj1]

Ok, with Mike's assistance I didn't drop my primary mirror... ? 

Which means to say the bolts on the 150PDS aren't *quite* long enough to achieve focus with my Canon 200d with the Baader click lock fitted.  We stopped when one of the three retaining screws had run out of thread ?.

When I add the Skywatcher 0.9x flattener/Cc, focus got slightly worse, so I do need to add a reasonable increase in screw length. I am currently sourcing screws that are 10mm longer than the current standard ones, and will post back. 

A shame, as I really like how securely the click lock centres and holds the dslr. I'm going to make this work! 

[Yearofthegoat]

Thanks for posting back.

That security is exactly what I wanted from the ClickLock system.  A real shame that they don't work with the focussers of possibly the most popular scopes out there.

[fozzybear]

Me to I have a 150pds and mpcc ditched the std adapter for one of these from https://www.firstlightoptics.com/adapters/flo-compression-ring-adapter-for-skywatcher-newtonians-m54.html yet to try with mpcc but works fine for visual holds ep's firmly I have clicklock on my c5 rock solid stuff..

[adyj1]

4 minutes ago, fozzybear said:

Me to I have a 150pds and mpcc ditched the std adapter for one of these from https://www.firstlightoptics.com/adapters/flo-compression-ring-adapter-for-skywatcher-newtonians-m54.html yet to try with mpcc but works fine for visual holds ep's firmly I have clicklock on my c5 rock solid stuff..

That adapter looks the same height as the original skywatcher one, so I don't expect you'll have problems - the Baader clicklock is a giant in comparison ?

That FLO version is a reasonable (and cheaper!) alternative, but without the self-centering and vice-like grip of the clicklock.

 

[Yearofthegoat]

- And apparently doesn't grip an MPCC without introducing tilt, which can ruin the effectiveness of the MPCC.

[fozzybear]

Never thought of that... tilt. in hind sight you buy product A then find does not suit it's purpose then buy product B it is a never ending circle why do not the manufacturers take this into account... Price i suppose. Oh well it was said if you went the AP route deep pockets... and many frustrated nights I have this all to come. I will be following your quest with great interest

[Yearofthegoat]

Yep, I've come to a bit of a dead end now with regards to centring a Canon DSLR with an MPCC fitted into a SW Crayford focussser. Unless there's some adapter out there I haven't come across yet.

FUFMPCC - not enough thread

Baader M54a ClickLock - too tall

HoTech SCA (w/ adapter) - too tall (as far as I can find out)

Compression rings - tilt due to clamping across the undercut in the MPCC nosepiece

 

But! I might still go with a ClickLock for visual - makes life easier for that anyway.

 

Edited October 27, 2018 by Yearofthegoat

[Len1257]

On 27/10/2018 at 16:52, adyj1 said:

 

 I am currently sourcing screws that are 10mm longer than the current standard ones, and will post back. 

 

Ady, I guess you must have sorted your screws out. I can see that you must have removed the mirror from its housing to get them in. Any further observations on thread size and length?

Edit: Having dismantled the mirror cell I found I couldn't shift the Sky Watcher screws so I'm thinking about adding threaded pillars to increase the gap. 

Thanks

Len

Edited March 2, 2021 by Len1257
extra investigation

[adyj1]

@Len1257, I have looked back on my records and used M5 x 40mm scews. I used 'shouldered thumbscrews*' for the tightening screws that you adjust from the outside, and countersunk screws from the mirror housing back to the outer threaded nuts.

* If I was doing it now, instead of the thumbscrews I'd 3d-print thumbscrew adapters for standard bolts that are normally adjusted with spanners (like Thingiverse link - although these are likely m4 size)

 

 

[Len1257]

Cheers Ady

Thanks 

Len

[Tymaishu]

Guys I wanted to share something with you. I picked one of these up the other day. They work fantastic with the Baader mpc coma corrector. 
 

https://www.teleskop-spezialisten.de/shop/Telescope-accessories/Adapter-extension-tube/Lacerta-Screw-Adapter-for-Baader-Coma-Corrector-on-Sky-Watcher-Newtons::3516.html?language=en