Hand held pictures

[Enrique]

I was supposed to get on Friday a camera adaptor for my GSO 12” scope. It did not arrive but anyway I went out and took pictures holding the camera against the EP. Here some results of Sirius (blue) Betelgeuse (red) and Jupiter. Please see if you can detect any problems with the optics. I collimated the scope before and during the session (every time I moved it). I forgot to write down the EP I was using. Next time I will. Most of the time I tried to get the speed to 1/30” or more, with less it was impossible for me to hold the camera steady. Some pictures have zoom+3, others have not zoom at all.

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[mickoking]

You can't really tell if there is a problem with the optics with 'hand held' shots like that. here is a hand held i did last year thru my 120mm refractor.

[Striker]

Enrique...to get a more accurate reading on collimation you will need to supply some out of focus star shots.....I just dont know how accurate this would be taking the shots through the eyepiece.

[asimov]

As Micko says, nearly impossible to diagnose collimation problems with hand held shots.

The camera would have to be mounted correctly & the star needs to be out of focus & dead centre in the FOV. High magnification is also recommended.

[Enrique]

Sorry, I misled you guys. I believe collimation is ok. What I have noticed with some Eps is that there is a reddish area on the top left of the object and a bluish one at the bottom right. I am attaching zoomed in pictures to enlarge the problem so you can see it. Also, sometimes I see like a v pointing to the centre of the FOV. I think it could be comma but I am not sure. I read it somewhere, I would have to find where I did.

As soon as I get my camera adaptor, I will do what you suggested. I will send you some pictures of stars out of focus so you can have a look at my “good collimation”. Maybe is not that good and I should improve it.

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<FONT size=3>I am also attaching picture of Saturn with a low power EP. You can notice the reddish, bluish there too.</P>

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[westsky]

Hi Enrique, as you have discovered the colour you are seeing comes from either the EP or the camera lens, you are using a mirror so there should be no colour seen even if the collimation was out.
The V shape you see can be a number of things, is the scope cooled?, is the seeing near perfect?
was this inside or outside of focus? the view will differ depending on which side of focus you are.
I think what you are seeing is atmospheric turbulence
take a look at this site it explains alot.
http://www.skywatchertelescope.net/EducationST.html

regards
david.