ZWO T2 Tilter

[Merlin66]

Some feedback on the ZWO T2 tilter.
This is effectively 11mm wide by 75mm diameter and has a female T thread on both sections. This means you'll need at least a T thread Male/male adaptor to mount the tilter between the focuser (or in my case a x2.5PM with T thread adaptor) and the camera (I was using the ASI 174MM).
The small knurled push/pull screws I faced towards the PM rather than the camera - to give better access.
Looking at your image on screen, and the direction of the Newton Ring banding the tilt adjustment should be at right angles to the direction of the bands (Make sense?) Think about it as the tilter "stretching" the width of the bands until they become invisible. 
You need to slightly loosen all the pull screws to allow the two halves of the tilter to separate and tighten them all up after adjustment.
In my case the tilt was 1.71mm gap which converts to a tilt angle of 1.3 degrees to effectively remove all signs of the Newton Rings. Majic!!
Oh, and don't worry about trying to find your Gaffa tape to cover the "tilt gap" -ZWO have thought of that and built-in a foam ring which keeps extraneous light out.
Conclusion: The ZWO T2 tilter does what it says - allows the removal of the Newton Rings.

[Macavity]

Interesting stuff! I did think of experimenting with my T2 tilter from TS.
https://www.teleskop-express.de/shop/product_info.php/language/en/info/p4745_TS-T2-collimator---compensation-for-field-tipping-in-astrophoto.html
Using Nylon screw to allow for a bit of... "flexure" in the attachment!

But looks like ZWO beats this for price and being specific to the job...
 

[Merlin66]

All I can say, is that it does what it says.

I'm very happy with the outcome.

 

[Davey-T]

So what's this all about ?

Dave

[Macavity]

28 minutes ago, Davey-T said:

So what's this all about ?

Heheh. I am (and remain) in a state of semi-bemusement!
I suppose, ultimately, you have to let it flow over you...
Not too happy with new DMK41, but resigned.
I suppose that's Solar Astronomy?
Ever the work-around?

Next time, I might spend my Dosh on that reclining chair!

[Merlin66]

I use the DMK 41 and DMK 51 - definitely NO newton rings with either.....

but the ASI 174MM on my system, as you can see, obviously had newton rings!!!

 

[Pete Presland]

Nice end result with the tilt adjuster, I have had very few problems with my DMK21au618 either.

[FLO]

20 hours ago, Davey-T said:

So what's this all about ?

Dave

It means images totally free of Newton rings. So, either we are wrong or Ken's camera needs attention. 

Ken, did we supply the camera? If we did we'll happily send you another for comparison. 

20 hours ago, Macavity said:

Heheh. I am (and remain) in a state of semi-bemusement!
I suppose, ultimately, you have to let it flow over you...

Not at all. If you see something wrong in any of our product descriptions please tell us so we can make amends  

Our ZWO product descriptions are based on manufacturers text, opinions of owners and our own findings. Until now we haven't seen, or seen reported, Newton rings in images made using the ASI174MM so we felt confident saying that. After posting this I will remove that line of text. 

Some time ago we had our own tilt-adjuster manufactured here in the UK, I confess I wasn't aware ZWO did one too. 

HTH, 

Steve 

[Merlin66]

Being in Oz, I bought my ZWO 174MM directly from ZWO....

unfortunately other users over on the Solar Chat site have experienced Newton Rings with this camera......

 

[FLO]

Just now, Merlin66 said:

Being in Oz, I bought my ZWO 174MM directly from ZWO....

unfortunately other users over on the Solar Chat site have experienced Newton Rings with this camera......

No problem, Ken  

We have updated our product description. 

[Merlin66]

Steve,

notwithstanding the NR the ASI 174MM is a great, sensitive, good sized chip, fast frame camera. 

It's been a good camera on the spectroheliograph with frame rates >400 fps.

 

[Macavity]

1 hour ago, FLO said:

Not at all. If you see something wrong in any of our product descriptions please tell us so we can make amends

I'm sure you would, Steve! My remark was intended as WRY, rather than specific or critical.  

It is my experience that Solar Imaging (particularly H-Alpha) is a severe test for any equipment.
Notably cameras! What works for a vast majority of people / setups may not for everyone. For
some people it seems that, what works on ONE day may not work on another. "Go Figure"? 

I do try not to pass opinion on equipment (and Real Life stuff!) of which I have no experience!
I suppose we could ALL prefix everything we say with "In my PERSONAL experience..." But! 
I actually do find (best effort?) Dealer Comments & User Reviews useful as part of the input...

[Davey-T]

2 hours ago, FLO said:

 

Some time ago we had our own tilt-adjuster manufactured here in the UK, I confess I wasn't aware ZWO did one too. 

HTH, 

Steve 

I have a FLO tilt adjuster and very good it is too, I think ZWO have only just introduced one for some reason 

NRs depend very much on the specific camera setup, focal reducer, Barlow or neither may / may not produce NRs with various camera / scope combinations and camera orientation so very equipment / operator specific.

I blame Newton for inventing them

Dave

[Merlin66]

Unfortunately the NR are caused by an etalon effect of the glass cover plate on the CCD -- some covers are thinner than others and the Ha narrowband agrivates the issue.