I thought flats should be the same length as darks and lights? Or is this applies in different scenarios? The latop birghtness on my laptop wasnt bright enough.
I read that you take takes flats and darks at other times, when the weather isnt too good for instance, and then create master flats and darks and use these for most processing, so that you can just focus on lights during imaging sessions and not the rest. Would definitely save time, as I learnt the hard way last night.
Thanks for the feedback guys
Ok, you can create a darks library, Ie, take 15x15min/15x10min/15x5min at ISO400, ISO800 and ISO1600, save these somewhere on your hard drive, and use them for your darks in your images you take from then on, although, temperature affects darks too.. So essentially you would need darks for every 5 degree difference in temperature... so, all the above images, for 5/10/15/20 degrees C... Thats a hell of a lot of darks to have, but it would make life fantastically easy from then on.
Now, Flats.... You can't make a flats library, becaues your flats will almost always be different.. you could get more dust on your scope, or clean dust off your scope, get dust in your camera sensor, or have your sensor cleaned, your focus position could change slightly, you could rotate your camera to more than 360 different angles in the focuser, all of these things would make a flats library useless. Flats need to be taken without having moved the focuser or camera....
Flats dont need to be at the same temperature as the lights/darks, so they can be done the next day... their exposure time varies on the brightness of the source.. it does not have to be the same length (nor should it ever be) the length of your lights.
OK, smart bum , ISO (im old) Yes, the black is heavily clipped, but then that hides the lack of flats
Quote:
Originally Posted by AlexN
I did this on my laptop, so if its atrocious, let me know
Even if its bad, it shows the data is in there, you just need to use photoshop, and keep working the image to bring it out..
I'll download your shots from the other day (that I forgot to do until now) and see whats in there...
Be careful when working with levels, as its easy to clip the black in search of a dark, smooth background in your image... better to have a bit of a gradient, and a bit of noise, than to clip the black and lose valuable data.
I tried to bring out more, but it just got noisier. Oh well, practice, practice. Might start from orig stacked and try again.
Is there ever a quick art to processing, or do even the pro's battle for hours on end tweaking images to try and get it just right? lol
I have the 'New Astro - Zone System for Astro Imaging' book, Im going to get stuck into.
Ok, you can create a darks library, Ie, take 15x15min/15x10min/15x5min at ISO400, ISO800 and ISO1600, save these somewhere on your hard drive, and use them for your darks in your images you take from then on, although, temperature affects darks too.. So essentially you would need darks for every 5 degree difference in temperature... so, all the above images, for 5/10/15/20 degrees C... Thats a hell of a lot of darks to have, but it would make life fantastically easy from then on.
Now, Flats.... You can't make a flats library, becaues your flats will almost always be different.. you could get more dust on your scope, or clean dust off your scope, get dust in your camera sensor, or have your sensor cleaned, your focus position could change slightly, you could rotate your camera to more than 360 different angles in the focuser, all of these things would make a flats library useless. Flats need to be taken without having moved the focuser or camera....
Flats dont need to be at the same temperature as the lights/darks, so they can be done the next day... their exposure time varies on the brightness of the source.. it does not have to be the same length (nor should it ever be) the length of your lights.
No worries mate... And I know for a fact some data takes me months to get it right...
My recent Eta Carina ha:ha+R:G:B shot took me 39 days between capture, and final process... I worked on it a couple of hours nearly every day...
I almost always to a quick rough edit to get a feel for what data is in the images, then attack it again, more gentle, to slowly pull the data out without generating tons of noise.. sometimes I'll produce 4 or 5 images from one set of data, all processed differently and just pick the one that looks best, and then make the final tweaks to that image to post on the forums/web..
It takes tons and tons of practice.. Im still learning myself, as I think everyone is...
Looks good
might want to try some very short exposures too like 1 min at ISO 400 to mask over the core to better reveal he Trapazium.
The field curvature is quite minimal really, I'd just crop it slightly personally (and save a few dollars).
cheers
frank
Thanks, I'll head over to dick smiths tommorow pick up the materials. Is there an easy to follow wiring readme for making the lightbox?
Here's a webpage for calculating the resistor but you'll need the data sheet from the LEDs to get the figures for the calculator. The data sheet should come with them. I used 4 LEDs in parrallel in mine, one in each corner, pointing to the back so reflections light up the diffuser.
[edit]
I put 2 sheets of foam board on the front so it just pushes onto the scope and I hot glued the round cutouts together so they push back into the diffuser as a cover when not in use.
Here's a webpage for calculating the resistor but you'll need the data sheet from the LEDs to get the figures for the calculator. The data sheet should come with them. I used 4 LEDs in parrallel in mine, one in each corner, pointing to the back so reflections light up the diffuser.
[edit]
I put 2 sheets of foam board on the front so it just pushes onto the scope and I hot glued the round cutouts together so they push back into the diffuser as a cover when not in use.
Thanks Tandum, I found quite a number of light box tutorials/projects online to give me further ideas.
Tonight I'll read more into lightbox design and construction. I'm thinking of using a variable resistor so I can adjust the brightness if this will work ?
Joke? I just went and sold my ED80 today J.k
, ISO (im old) Yes, the black is heavily clipped, but then that hides the lack of flats 
J.k
