Telescope Reviews: AP Images Taken with Original NexStar

Hi Mgauthier,

Many thanks for the information regarding the type of camera and 'scope combination you are using. That helps to put things into perspective.

I use Photoshop CS2 for processing so unfortunately I regret I'm therefore not familiar at all with the features of Paint NET but I'm sure it contains the following :

Levels.
Curves.
Brightness/Contrast.
Colour Balance.
Hue/Saturation/Lightness.
Unsharp mask.
Gaussian blur.

These features, common to most processing software packages, are about all I am manipulating in P/Shop.

If therefore Paint NET does indeed possess these features or most of them, the best way to learn basic processing is merely to practice with them. Thus if you don't have a sufficient number of potentially suitable images of your own on which to practise, then download a few posted here on these CN forums. (I'm sure no poster here would object so long as his or her image was only used for this purpose).

Another aspect to consider though is one of image scaling. Your combination presents a reasonably, (and thus often sought-after) wide field. However, as you can no doubt appreciate, this is not always advantageous.

Thus for example, if you wished to image the Ring Nebula, M57, its planetary size would be lost in a sea of background stars ! Here therefore, the use of a Barlow lens might be beneficial. Conversely, the whole of the vast Andromeda galaxy might fit nicely into the frame but only via the additional use of a focal reducer.

I don't know if you already use it, but I find the "New Astronomy Press CCD Calculator" an extremely useful software tool for deciding how any particular object will "fit the frame" depending on the set-up used.

If it is of interest to you therefore; here's the link:

http://www.newastro.com/book_new/camera_app.php

Attached also is a screen shot to demonstrate. Note that if you wish to use it, your Canon 1100D is not actually listed, but that's of no consequence. You merely need to enter the necessary parameters from your camera's specification.

Finally, on the subject of vignetting. Perhaps you'd like to post what you consider to be a vignetted image and I'll take a look at it with a view to adjusting it. When I've then figured out what I'm doing, (if I can) I'll let you know if I can provide a solution !

Hoping this helps a little,

Best regards,
Tel

Edited by Tel (10/15/12 07:05 AM)