Rosetta Nebula NGC 2237

This is an image that I took the weekend before last but I stopped short of the number of frames I wanted and therefore did not post. Dave and Philip think I should so here goes.

webtreatz.com/component/option,com_zoom/...ageNo,1/key,5/hit,1/

Later,

Jed.

That's a fine image Jed. Very good detail.
Just wondering about the WO. That's the semi-apo yea?, not the flourite I presume? (I'm on the look-out for a small scope for astrophotography at the mo hence why I ask). Colour correction seems pretty good. The very edges of the field seem to suffer slightly though from field curvature.
All said though, that's a great image!

Very nice.... You shooting flats yet?

Dave

DaveG and Philip are right.
That's a great image. Pic of the day stuff.
Also nicely showing the open cluster NGC 2244 in the centre.

Well done Jed

clear skies

Johnno

Incredible detail, pinpoint stars! The WO is a greta performer, that one is for keeps.

Ok, Here is one of my stupid questions again:

You shooting flats yet?

How do you take flats?

Keith..

Flats are taken of a 'uniformly illuminated field' - ie no gradients. What's it for? Well, it records the characteristics of the whole optical system, including the camera. So if you have any dust motes, vignetting, etc, flats can eliminate or at least minimise them.

Hopw do you take them? Well, there's a number of techniques - point the OTA at the twighlight sky (dawn or dusk). But you need to avoid saturating the CCD - I think you go for 50% saturation but I'm not certain. You can use a light box or, what I've done in the past is take T-Shirt flats...

Yet another reduction frame - and you thought astrophotography was easy...

Oh - and you have to take darks for your flats :roll: ....

Cheers

Dave