Flats with Long period data collection

[libraryman]

Not sure how to ask this question but living in the UK its difficult to collect enough data over a short period, I have recently collected all my ha data for my target, its likely now to be next year before I can complete the 0111 components.

My problem is that I only have the one camera and I'll want to swap it onto another scope for a narrower field in the spring.

My question is: if when I refit the camera to my wide field scope can I continue to collect the 0111 to add to my current ha? (Assuming the same orientation)

I have flats for the ha now, if I move the camera and take flats for the 0111 when it is collected can I mix them???

Logic tells me I can, once the sub's are stacked with their own flat fields darks etc.

Ray

[swag72]

You can certainly add the OIII to the data later on. You already have your Ha, so when you come to take your OIII try to line your camera up to the same orientation as your Ha as this will ensure that you lose the minimum amount of data in your field of view. Then take your OIII as per usual and also your flats to suit that data.

Stack them as per usual and you have a calibrated and stacked OIII sub that can then be used with your Ha from a year previously!

[ollypenrice]

Madame is both succinct and correct! 

One little tip I throw around a lot, based on having made life difficult for myself in my early days, is to set the camera orthogonal with RA and Dec either in landscape or portrait. This is easily done by slewing slowly in one axis while making an exposure of a few seconds. The resultant star trails show the camera angle. Just get them vertical or horizontal and then it will be so much easier to reframe an image in a year or two. Finding a random camera angle again is utterly exasperating and incredibly wasteful of precious time.

Olly

[ChrisLX200]

Madame is both succinct and correct! 

One little tip I throw around a lot, based on having made life difficult for myself in my early days, is to set the camera orthogonal with RA and Dec either in landscape or portrait. This is easily done by slewing slowly in one axis while making an exposure of a few seconds. The resultant star trails show the camera angle. Just get them vertical or horizontal and then it will be so much easier to reframe an image in a year or two. Finding a random camera angle again is utterly exasperating and incredibly wasteful of precious time.

Olly

or... if you use SGPro it has a 'manual' camera rotator, so it will use a plate solver to tell you how far (in degrees) and in what direction to turn the camera to match a previously plate-solved image (i.e., load the old image into SGPro and solve it). It's an iterative process and will get you very close quite quickly. A motorised rotator is quicker of course (but that's cheating :-) )

ChrisH

[libraryman]

Thank you all, I do indeed use SGPro so that tip and Olly's are in my saved box.

I have not enjoyed good weather or opportunity lately so its going to be a looong task!

Ray