Discussion in 'Astrophotography' started by PMCC, May 3, 2015.
More milky way... I start to want a Samyang 12mm
Sgr150426b by PMCC posted May 3, 2015 at 5:56 PM
Great use of foreground subject! Pity there's so much noise... what lens did you use?
What's the light in the distance btw? It looks like sunrise or something :-S
I just have the 14-45 kit
I donno, maybe some better PP technique can reduce the noise further?
Yeah, you could try stacking many long exposure together for instance.
I already stacked 6 frames but the noise is coming back after pulling curve in PS.
Interesting. I find that stacking 6 is pretty good with my f/3.5 fisheye. The original files have to be very well exposed though.
I am experimenting with a way to pull curves without increasing noise too much. That, together with stronger NR, yields this
Sgr150426d by PMCC posted May 5, 2015 at 6:14 PM
An improvement I think. One thing you might want to try is to separately adjust luminance noise reduction and chroma noise reduction. The luminance noise is less objectionable, whereas the green/red chroma noise is more obvious.
You can also try dark frame subtraction. Make an exposure with the same settings as the original only put the lens cap on for it. That will give you a dark image with the noise pattern in it. Use DeepSkyStacker which has an option for dark frame subtraction which will remove the noise but leave the rest of the image. I've used it with varying success. I've been using the Olympus 12mm F2 lately for my night photography and love it. Though it can be expensive you can find it cheaper used, usually under $500. To me it's worth it because I use it in daylight and it's AF is FAST and great IQ. At night it's a great light gatherer. The 45mm 1.8 is another good one except it doesn't have a focus scale which annoys me.
Your 14-45 is too slow for the job. @ f/3.5 and depending on the light, you may be forced to shoot @ 3200 or even 6400. Not great for getting clean files. If you have to pull exposure, I suspect that you're stuck with trying to get a milky way with a shutter speed (due to 14mm FL) that might underexpose the shot but also need to prevent star trails from happening. Not a great place to be.
I find that if I want to shoot the milky way or any night scapes of dark skies, I need to stay within ISO 640 and 800 or max 1600 with my E-P5. I found 800 is the sweet spot, so I actually have a special setup for this as I use a combination of a focal reducer and a Bower 14mm f/2.8 full frame lens, which gives me a 10mm f/2 lens. With this setup, I get cleaner files, wide enough focal length of astro-scapes and the setup is pretty affordable. The Bower was on special for $249 and the focal reducer was $110 for a total of $359. The downside to my Mitakon focal reducer is the flare from any bright light source. This setup is only for manual focus, which is all I need for this application. Infinity focus is good too with these 2 combinations.
In my experience, anything below f/2 is a good start. f/1.8 is better, but f/2 and f/1.0 are the best. With this setup, there is no reason to lug out a full frame unless yours is a Nikon DF or Sony A7s. Now only if Olympus develops high-rez shot sensor shift that is fast enough to render the image without generating star trails and anomolies, then that's a body I like to get because multi-sampling reduces noise further and improve color accuracy -- so bye bye to full frame.
Highly recommend the Samyang 12mm. Has produced some great night sky pictures for me attached to both a GX7 and EM1. I've been having a lot of fun with Live Composite on the EM1 for star trails. Very cool feature!
With the fisheye you can use longer exposures, though, since it is so wide
Light pollution is also a problem. It decreases contrast and limits how much exposure one can go. The bigger problem is, of coures, I don't have much money
Actually Pentax has a gadget like that, using sensor shift to track the stars. However, a tracker is cheaper.
I've taken shots with the Samyang Fisheye, straight up, that were 60 second exposures, and it's too long, the stars have turned into short streaks. 20 seconds is about all you can get away with.
Biker hiker, I'd love to see some of your MW shots (particularly the frame edges) w/ the 14mm+focal reducer. Which reducer are you using?
I've been using the Oly 12 f2 w/ the E-M5 & love it but need wider to do aurora well. IMHO, F2 is min. aperture for good MW images w/ today's m43 sensors. I shoot ISO 3200 & use DXO OP 10 Prime NR software w/ good results. Decentering in y 12mm prevents stacking form working well however.
NR3200_8270029 by tradesmith45, on Flickr
Been considering the new SLR Magic 10mm t2.1 but no detailed reviews have been done yet. User comments are mixed regarding edge IQ from "as good as the Oly 12mm" to " "a bit soft wide open". Not enough to lead me to buy a $800 lens just yet. And I'm doubtful the Voightlander 10.5mm f0.95 will provide usable MW images at apertures larger than f2 so not willing to pay even more for wasted larger glass. None of the Nokton tests I've seen show these lenses perform well wide open at least for stills. Maybe ok for video & street photography.
Depending on the focal reducer cost, your approach could be cheaper.
There is now of course the 8mm f/1.8 fisheye!
Yes but I've just never gotten excited about FE images.
One of the options I'm seriously considering is the Samyang/Rokinon 12mm F2 in m43 mount ($300 new, $250 used) and a used or older Nex body (can be found for $200) plus a m43 to Nex lens mount adapter (Fotodiox has one for $25). I'd get an excellent APS night sky setup and the lens gives me a fast 12mm with my m43 gear. Some of the Nex bodies (or possibly a A5000 etc.) are small and lightweight so not too much extra to carry around. Seeing as you already have the Oly 12mm this doesn't offer you the same advantages but it's still a better and reasonably affordable option for a fast and super wide prime (that also accepts filters).
Yes, I've looked at the Sam 12 & APS options too. The lens has a couple weaknesses compared to the Oly 12 - much worse /CA & an additional -1ev vignetting. Resolution at max aperture is as good & coma is well controlled. And only a few of the older sensors match the current Oly sensor for hi ISO performance.
Every time I start considering UWA options for larger sensor cameras, vignetting &/or edge IQ/CA become a concern especially for FF cameras such as the A7S. A couple of the WA/UWA lens options I examined for the Sony A7 had >3EV vignetting. I've never seen a discussion of the impact of strong vignetting on night sky shots. Correcting that in post has to produce more visible noise in the corners but I have no idea how much of an affect it will be on a final image. I'm pretty confident a camera like the A7S would have no problem w/ -3EV vignetting but not sure about other sensors.
And I'm pretty certain using a tracker to get longer exposure would do more to improve detail in MW shots than switching to a larger sensor. And trackers are cheaper. I've realized most night landscapes need 2 exposures - 1 for sky & 1 for landscape so even w/o using a tracker will have complex post processing.
At least those are my tentative thoughts. Haven't bought a tracker yet either-
Results from trackers do look really good but I don't know how small and portable they get (in my case I would want something I could backpack with). I've seen the iOptron Sky Stacker that sounds pretty good and not too much weight but maybe there are even smaller options... Before I start to consider a tracker though, I plan on getting something wide (and hopefully fast) that I can use for both night sky and general purpose. Depending on how much use I think it will get I might look into a tracker later on.
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