Single 6 minute shot with mod canon 450D

[pixueto]

Hi there, I just wanted to hear your oppinion about this. I have recently modded my canon 450D and only so far, managed to take a few test shots. I did not use any guiding and the night was a bit windy so you can see in this 6 mins sub that the stars look like gherkins. Nevertheless, I am quite impressed with the detail gathered in this 6 mins sub. All I did was a bit of stretching in PS, applying some luminance.

Also, I wanted to ask you: I've never collimated my SW200P. Do you think that the image is loosing resolution because of this?

Thank you very much for your help.

[Tim]

Hi,

The modding benefits are obvious here

You wont be losing resolution as such, but you will possibly be operating below par.

For instance, the light cone isn't centred on your chip, look at the vignetting on the rhs of the pic. Good collimation will fix this.

Can't tell what state the stars are in in this piccy, but having good collimation will make them be the best they can be across the widest part of your frame.

And finally, everything will be a tad sharper, not so noticable on nebulosity, but on stars and bright objects it really shows.

[pixueto]

Thank you very much. So with good collimation the vignetting will end up in the centre of the image? I assume it will still be there, isn't it? I mean, good collimation won't get rid of that vignetting, right?

[Photosbykev]

a good set of flats will remove most of the vignetting

[Tim]

Thank you very much. So with good collimation the vignetting will end up in the centre of the image? I assume it will still be there, isn't it? I mean, good collimation won't get rid of that vignetting, right?

Correct. Any vignetting that remains will be equally spread around the centre of your picture.

If you exaggerate in your minds eye the effect of the camera being tilted off centre from the mirrors, you can picture that one side of the chip will be closer to the mirror than the other, which affects focus.

I'm really tired and struggling to explain it properly at the moment, hopefully somebody more eloquent will join in

Cheers

[Tim]

a good set of flats will remove most of the vignetting

This is very true, however you are best to get it as good as can be in the first place by centralising everything.

Dont be afraid of collimating, there's nothing to it

[Photosbykev]

This is very true, however you are best to get it as good as can be in the first place by centralising everything.

Dont be afraid of collimating, there's nothing to it

agreed, flats are the last step in removing vignetting not the first

Sent from my iPhone using Tapatalk. Blame Apple for the typos and me for the content