Problem with Flats

Well now, having taken a trip to your website...

I have to say that I'm not surprised you Crab is superb and that the Eagle really is excellent. I didn't know you had a Tak... It is true what they say though, you get what you pay for. Still, it does require skill to operate high end gear and your images do show what can be done with quality equipment.

I recall my first Eagle image - nowhere near as good as yours but as you say, it's mine

As regards the journey, I agree. I've placed milestones along mine and have been lucky enough to achieve them all. The last two years have been unfortunately taken up with other matters - life does get in the way somewhat - but hopefully I'll back in the saddle this year and continue on.

All your images are very good indeed - where are you based? You must have pretty good sky conditions...

Dave

Lucky to be in Spain at the moment and have clear skies here more often than in Ireland which has been a big incentive to start this hobby. I still need a shed here though....it gets very cold here too at 0400hrs

You made me smile about your first Eagle - mine is tucked away where nobody but me will see it...... I have come a long way in two years and have a long way to go still, but as long as it is enjoyable....that is all that matters.

Re the TAK: a great second hand buy and worth the money. Highly recommended for photography.
Time to go out and see how it is doing......have it working away right now..

Thanks for the kind comments.

Kinch

Dave
What do you mean by Characterisation?

By the way NB = NarrowBand

Simon

CarlightExpress wrote: Dave
What do you mean by Characterisation?

I'm guessing Dave is on about measuring your own gain, dark current, readout noise etc. I did it for my camera recently and the results were a little different from the numbers I've seen quoted, I'll get around to writing a review of the camera one of these nights! Doing it will give you an idea of where your noise is coming from, whether you need darks even, what your minimum exposure length given your skies and read noise etc.

Have a look through www.stark-labs.com/craig/articles/assets/CCD_SNR3.pdf for the details on doing it, and www.stark-labs.com/craig/resources/Artic...ws/Atik314_API09.pdf has a review of the Atik 314l+ based on those tests.

At least I think this is what Dave meant by characterisation. Apologies if not

Hi Simon - DANG! I knew I knew what NB meant :blush:

Albert you're correct - I didn't look at your links because the pain of going through the process (3 years ago) is still painfully fresh. Actually, I've just started sweating again...

Simon - in all seriousness, doing it is quite simple - really. Doing the calculations is a little trickier but with the help of a spreadsheet (I have a template), it's OK. The issue I had 3 years ago was doing the initital research - with the help of the folks here and a couple of lads on the Finger Lakes boards, I eventually figured out most of it (there are still some parts that look like black magic to me...).

Luckily, I logged the journey on the boards here and other folks jumped in with tons of good advice. Take a look at this: www.irishastronomy.org/index.php/kunena?...d=87780&limitstart=0

There are a number of links peppered through the thread that might help though Albert's may be more up to date.

If you need any help etc., just shout. I think I still have the Howell book somewhere. I probably locked it in a case within a sealed trunk inside a double-skinned safe in my padlocked garden shed. I'm sweating again...

Dave

albertw wrote: I did it for my camera recently and the results were a little different from the numbers I've seen quoted

Significantly different? or just a tad? The write-up, if you get a chance, would be an interesting read.

As another slight aside to this topic, there's an interesting thread on the FLI group at the moment about bias stability (ref temperature) and using the overscan region of your CCD (if there is one). As it happens, PixInsight apparently has the ability to use the overscan region of the CCD to calibrate dark, bias and light frames.

Dave