|
A great shot Rohan.
I would have thought though that it would be brighter at ISO2500 and 121 seconds. I guess the F4.5 is what did that. I did a lot of expermentation myself over 3 clear nights this weekend with several cameras, several lenses and a precisely polar aligned Polarie. Ideal settings varies with the lens, the camera and whether to use auto white balance or set a colour temp white balance with perhaps a custom offset for green and magenta.
Too long an exposure and you get blurred foreground. You can take a separate foreground and layer it in Photoshop but now its a composite which is not always popular due to too many fakes on the net.
I have only used a Canon 20D and 40D and briefly a 5D2. I think with the Canons (Mike, Greg Gibbs, Colin, Humi would know for sure) the white balance is probably best set to a temp. Otherwise the images I see when they are not are too brown and the subtle blues, yellows and whites are missing. Also the sky is rarely brown, its often a light green near the horizon or grey. I imaged on the weekend and I was getting almost a red/orange but then there was backburing smoke around.
So I would experiment with the white balance. Perhaps setting it to a setting like daylight may work. Again I am more familiar with other brands. With Nikon 4200K works well. With Sony and Fuji auto white balance is hard to beat.
Don't forget these DSLRs etc are optimised for daylight photography and not for nighttime work at all (hence the ridiculous limit of 30 second exposures, the lack of a proper night white balance setting, the need for intervalometers with some brands and the lack of a decent live view setting for manual focusing at night).
F4.5 is getting a bit dim. But I don't know what you lens looks like wide open. Being a zoom probably it shows too much chromatic aberration and coma but that is most likely under control earlier than F4.5. I'd check that out.
You may have to knock back the reds in your custom white balance if you use the temperature. Its probably excess red that is giving the brown colour bias?
There's a lot right with this image and the nice tight round stars, the Milky Way is a tad underexposed but still prominent, the framing and composition is great (not everyone likes portrait orientation though - but that's getting into subjectivity).
Now the nights are getting colder ISO3200 may be ok and with long exposure noise reduction it may be fine (again you need to experiment with your camera for this).
I think one approach is to experiment with your camera and your lens to find the optimum settings. It can take a little while. Then once you know your exposure you can standardise it and make some library darks. I dont know yet if flats are worthwhile with this sort of imaging. Probably not but I may try it and see. Lightroom and other programs have vignetting control so flats may not do much.
Greg.
|