Collimation problem or?

[Paul1]

Hello ,

First light Epsilon E130D F 3,3 

This are 6 Lichts widht no darks en no flats of M45.

6 Lichts x 300 sec stackt in DSS.

I see square stars,is dhis an collimation problem or something else?

Regards Paul 

[johnrt]

The Epsilon has pretty thick spider vanes and I think your square stars are caused by this on the bright stars. I would say your collimation looks pretty good!

[Dave In Vermont]

I agree - and your capturing the beautiful nebulosity and the stars of M45 is wonderful!

Do keep going -

Dave

[derrickf]

Hi Paul,

I could be wrong, but the thick diffraction spikes make me suspect that the focus may have needed a tweak. John RT is correct that thick spider vanes and large pixels can lead to square stars but you would still expect the diffraction spikes to be very narrow and sharp when focus is good. Less than optimal focus would exacerbate the square star shape.

 

HTH

 

Derrick

[Ikonnikov]

7 hours ago, derrickf said:

Hi Paul,

I could be wrong, but the thick diffraction spikes make me suspect that the focus may have needed a tweak. John RT is correct that thick spider vanes and large pixels can lead to square stars but you would still expect the diffraction spikes to be very narrow and sharp when focus is good. Less than optimal focus would exacerbate the square star shape.

 

HTH

 

Derrick

Hi Paul,

Yes I agree with John and Derrick, you can see some double diffraction spikes throughout the image confirming that the focus is out. I have owned an E130D for about 10 months now and it took a lot of work to get focus, collimation and chip spacing/orthogonality acceptable. Good news is when you do the stars are actually fairly round at least with my current camera with smallish (4.5 micron) pixels though you can't really avoid big diffraction spikes. Below is 5x10 mins on the horse-head through an IDAS filter with just background removal and a simple stretch, stars aren't very tight but reasonably round for the most part. I appreciate that my chip is quite a bit smaller than yours though which makes life easier.

I started by investing in a micro-focuser (but have now moved to a computerized motor focuser) then bought Catseye tools (plus custom adapter) to get collimation accurate and finally spent lots of time fiddling with camera tilt and spacing. 

 

Paul

 

 

[Paul1]

Sorry guys for the late replay.

I focust with an bathinof mask and I own a micro-focuser.

Is it not possible that my  mirror is pinched?

Regards Paul 

[Tonino]

Hi,

I've got a Sky Watcher Evo 6 inch f8 f1200mm refractor, haven't had it that long, I think the collimation may be a bit off? I'm not entirely sure, I've tried testing it a few times with different eyepieces, first of all with 32mm Plossls, the stars seemed slightly elongated and pointy to one side (Sorry don't have any pics to show you), not really lovely, crisp, sharp, round and pin pointy as they should be? Then I tried my 10mm wide angle lens, seemed a bit better with this one though for some reason. Don't know if it's something to do with the atmospheric conditions/dew, my different eyepieces or even my star diagonals perhaps at fault, although when I tested it out later on in the night to point at Jupiter for the first proper time it seemed fine and sharp (With my 8mm anyway), then I tried the 32mm Plossls again there was a bit of ghosting and elongated/stretching of the planet and a bit of colour fringing now again around the planet, and the Galilean Moons looked a bit starry pointy shaped, but I think that may be the fact that my telescope is only an f8. Not really sure how the starry view should look through this particular type of telecope? Perhaps it pertains only to this particular telescope type, optics and model anyway? Not entirely sure what proper collimation is supposed to look like through the Evo? Do you think I should try and collimate my telescope? I'm a bit concerned that I may make it worse, also I've never collimated a telescope before, I've heard it could b a bit daunting and fiddly! Or leave it as it is? What do you think guys?

P.S. Lovely pics above Paul, those stars look perfectly finely detailed and crispy sharp to me anyway.

Tony

 

[cardconvict]

Lovely picture buddy but watch that dust the stuff is a nightmare on the sensor

[jsmoraes]

Double spikes means out of focus. Try to adjust it before to check that your optics is ok. The spikes must be like ikonnikov image: single and thin.

[Paul1]

Thank you guys for the information.

I thing I' try first to taken an other picture an try to focus beter,before I check my optic. 

Because I thing my collimation is pritty good.

 

Regards Paul