First steps with DSLR

[Abernus]

Hi all.

Since the last thread on how to get a RA motor fitted to my EQ2 or CG? mount the motor is now fitteed and working. I know I can probs get a max of 60s before trails start to become an issue. So I would lik some advise

I am going out tonight as the sky should be clear and the wind will be down to 9 mph. I am going to target the Horsehead or Orion Nebula or Pleadies (all should be easy enought to find now for me) The problem I have is all this talk about darks, flats Bias etc

I understand I need to take normal exposures of the object and I will need to experminent with what settings to use (any advise on those would be great).

I also think I understand from reading that I take about 10+ exposures outsie at the same setting with the lense cap on to help eliminate Hot Pixels when stacking.

But I don't understand the need for the Light and the Bias or what they even are and how to take them.

Any advise or pointers to guides would be a great help, I am not expecting great images tonight, but even a blury outcome would be great.

I will be using the following:

4" Meade reflector

EQ2 style mount

Canon EOS 10D unmodded

guided with RA motor (max 60s)

I also have a selection of colour filters to use if they will help?

Thanks

[Shibby]

Hi Abernus, welcome to the slippery slope of imaging. By "light" frames, we mean the normal exposures (without the lens cap); your actual useful data. All the other types of exposures are known as calibration frames. Settings-wise you will want RAW mode and a fairly high ISO. Try 800 to start with.

You've already correctly identified what darks are (the subs with the lens cap). Bias calibration is contained within the dark, so you don't need to worry about these.

Flat frames are for removing the inherent dust marks and vignetting caused by your setup.

I recommend using DeepSkyStacker to stack your images. The user guide contains excellent description of the different types of exposures and how to take them.

Also, have a good look around this forum as it is also an excellent resource. The "Tips, Tricks and Techniques" forum has several handy tutorials.

[themos]

At 900mm, your focal length should be good for framing the Pleiades and as they are bright, finding and focusing should be easy, so start with that. Start with short exposures and work up until you start seeing star trails. I suggest forget about calibration frames for now: aligning your mount, mounting the camera, finding and framing the object, focusing and fiddling with the camera controls will take up a lot of brain time!

[Shibby]

themos has a point. It used to take me hours to get set up, aligned and focused. If you're going to take any calibration frames, darks are quite useful and easy to take.

[themos]

Or you could just record the temperature and shoot darks another cloudy night with similar temperature. I'd say if you want to get some calibration frames, flats are more of a priority (but quite tricky to do).

[Abernus]

Thanks for the info. I have clear skies now but am going to wait another hour or so. Then it's off to get some warm clothes on and step outside for a few hours to try all this imaging malarkey

[themos]

Practice with changing camera settings indoors! Same with mount controls!