My first Leo Triplet

[batema]

Hi,

I thought I would post this at this rediculous hour because the clouds rolled in and stopped my mate and I imaging Jupiter.

Talen using my W/O Flt 110 Flourite and Canon 400d unmod ISO 800 stacked using DSS and processed using Photoshop CS3 for only about 20 minutes. The reason it only took 20 minutes is because I don't know what to do after that.

Image is 12 x 10 minutes lights with 8 x 10 minute darks. No flat as you may be able to tell with my lovely dust mites and I used a paintbrush type tool to get rid of a satellite trail through the guts. Guided usinf PHD. The temp was 21c so am very happy with the results.

I had to slightly crop image by about 20% as I also had to flip the scope half way through.

Any advice welcome.

Mark

[Alchemy]

youve got some detail there. a quick way to remove trails by sattelites is to use a median combine when you stack.

[iceman]

Lots of detail - but you're doing yourself a disservice not using flats. It will improve the image quality a LOT!

You're collecting lots of data but you're letting yourself down by not doing full calibration.

As Clive said, median combine is the best to get rid of those odd things in single frames like meteor strikes or satellites.

[Liz]

Still a great pic, Mark, lots detail on the galaxies!!

[h0ughy]

nice work - but i too used to cut corners - it doesnt pay to do that.

[Craig_L]

Great detail there Mark. Maybe a tad more colour could help.

[batema]

Hi,
I was excited at 4.15am this morning when I processed my stack of images. I'm worried about my next question in relation to processing as it may be the most fediculous question in the history of these posts.

Mike or anyone, I did take some flats 20 of them at the end of February in the morning pointing straight up with the white shirt method. Do you think I could use these flats with my Leo Triplet shots????

I also set the parameters in DSS for average to stack on my lights and then median for the darks. Should I set everything to median?

Also what does full calibration mean in relation to processing? For this image I basically did a colour balance first, then set my black points (15,15,20) and my white points (245). Then curves, levels (reset points) until I think looks OK. Then flatten image Select Colour manage then modify contact 4 feather (i dont really know why) 3 then unsharp mask, noise reduction and slight gausian blurr.

Any suggestions. I have been reading Zone System and Photoshop for astronomy but a couple of other suggestions would be appreciated.

Mark

[Alchemy]

you can set all to median, or whatever you wish , there are varying methods with benefits ... try all and see. as previously said median will remove the satelite trails from the light frames.

a full calibration set is as follows, and all can be put into deepsky stacker.

light frames.... your exposures ie 5 min
dark frames ..... same exposure as your light frames , note at the same temperature does help, you can make a bank of these at say 20 deg, 22 deg etc and then use with your lights, you probably should update periodically say 6 mths or so as a camera can change over time particularly dslrs.
Flats...the t shirt method to expose as a grey so you can see full tones at all edges and core ... no blacks or white. if you are using a dslr then dust may accumulate on your chip so if you have a clean or you start noticing extra dust, its time for new flats.
Flat Darks.. these are darks exposed at the same length as your flats. it might be 1 sec or less.... just set your flats manually and then do your dark flats.
bias...this is a dark exposed at the minimum exposure, ie 1/4000 of a second which covers the readout noise.


that is a full calibration set, do these when stacking then do your other stuff afterwards, in photoshop or whatever you prefer.


clive

[batema]

Thanks Clive

Mark

[iceman]

You don't have to go the full extent of flat darks and bias. I really just meant flats and darks. Flats make a HUGE difference to your final image.

You won't be able to use flats from the february session. Unless you have a permanent setup where you don't change the camera angle, focus etc, then you have to redo flats after each session.

Make yourself a lightbox so you can do them at any time after the imaging session, before you change focus, camera angle etc. Using t-shirt and sky flats is fine but surely more inconvenient than a lightbox.

Median combine for lights will get rid of the satellite trails etc. So yes, you can try it for your lights and your darks.

[Hagar]

Hi Mark, I have posted my thoughts on calibration etc on your question post http://www.iceinspace.com.au/forum/showthread.php?t=44268.

As for this image. Very nice except for a few imperfections and a bit of noise. None of these are unable to be fixed. The real outcome for this image is that it is finished. Appart from a few processing tricks you will really need to start a new image to fully calibrate and you will notice the huge difference.

Keep at it.

I hope you don't mind but I have included a copy of your image that I had a quick play with. Some selective sharpening, Background masking and a bit of DDP stretching.
Probably a bit much but it will give you an idea of what can be done.