Can you manually focus to infinity with the 12 f2 (for astrophotography)?

Discussion in 'Native Lenses' started by LowriderS10, Feb 4, 2015.

  1. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Hi all,

    Just a random question...one of the few things I hate about my lenses is that they're all focus-by-wire. This means that I'm having a horrendous time a lot of the times trying to focus at night...in the old days with a DSLR, I just bumped the focus ring to infinity, pulled it back a hair and got perfect shots every time. Not so with Oly.

    But I see that the 12 f2 has a unique design and a distance scale...does this mean that one could achieve infinity focus at night reliably?

    Thanks,
    T
     
  2. eteless

    eteless Mu-43 All-Pro

    Jun 20, 2014
    If you mean focusing on stars and distant objects, live view boost combined with high magnification generally makes it pretty easy.

    The manual focus clutch can focus past infinity, however it focuses past infinity probably the same amount as most DSLR lenses, so that's not saying much.
     
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  3. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    I've tried the LiveView bit, but maybe due to the pollution where I live, even if I'm getting good pictures, I'm finding it impossible to see anything on the LCD for focusing. (Usually I focus on the farthest available object and just shoot UWA at f4 and do star trails, so it's not an issue).

    How much past infinity can it focus? (As in, is there a physical stop to its rotation in MF mode?). I would be perfectly okay with that, as that's how I used to focus DSLRs...crank it past infinity 'till it hit the stop, then pull it back a little bit...worked like a charm every time. :D (But with the lenses I have now, the focus rings just turn, turn, turn forever).

    Also...is the focus scale on the 12mm useful for this kind of thing?
     
  4. eteless

    eteless Mu-43 All-Pro

    Jun 20, 2014
    Yeah, it has a physical stop. You can go to the stop and pull back a bit and it will be *near* infinity, however it's hard to tell exactly how close it will be without looking on the screen.

    The focus scale is approximate, however by memory it doesn't have many distances given it's a 12mm lens... I mean basically everything is going to be in focus even at f/2.0.
     
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  5. Halaking

    Halaking Mu-43 Top Veteran

    667
    Dec 17, 2012
    Los Angeles
    Morris
    I usually set somewhere around distance mark "3", it's next to the infinity, it works well for stars.
     
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  6. pellicle

    pellicle Mu-43 All-Pro

    Feb 10, 2010
    Southport, OzTrailEYa
    pellicle
    Hi

    some things ...
    1) focus on the brightest furthest object in the terrestial area (not a star). With a 12mm it will be effectively the same.

    2) bring a laser pointer and focus on the dot (projected on something distant but reflective), for a 12mm that'll do too

    3) when I use the "zoom focus" (where the finder shows the 100% pixels of the sensor area where the focus point is) to its maximum in manual focusing the finder becomes much brighter. Of course I only use a camera with an EVF for this ...

    lastly, be careful with shutter speeds, if the shutter speed is too slow there will be some movement of the stars and that will appear as coma distortion.
     
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  7. RobWatson

    RobWatson Mu-43 Hall of Famer

    Boost is the important bit here. If your camera has the boost feature in live view turn it on for a very significant improvement in low light situations.
     
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  8. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Thanks! What's the boost function? I have an E-M5. I usually just do the focus point magnification...but it's proven to be unreliable for the most part.
     
  9. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Thanks! Yeah, I generally try to stay under 25-30 seconds if I'm not going for movement (which is part of the reason I'm thinking about getting the 12, as it's 2/3 stop faster than my 14, and a 1 2/3 faster than the 12-50 and 2 stops faster than the 9-18, thus allowing me faster shutter speeds).

    I've tried the bright stuff, but it just doesn't work...however, the laser pointer is a brilliant (pun intended) idea...I shall try that...thanks! :D
     
  10. barry13

    barry13 Super Moderator; Photon Wrangler

    Mar 7, 2014
    Southern California
    Barry
    EVF Boost, makes the EVF display much brighter in dark conditions.

    Search the manual or look at the em1 guide on biofos.com

    Barry
     
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  11. jpig

    jpig Mu-43 Regular

    88
    Oct 21, 2011
    You might also consider the Rokinon 12mm f/2. No AF, MF only with a real mechanical (not by wire) focus ring and hard stops. Somewhat larger and heavier than the Oly, but also a lot cheaper. I got one for astrophotography and like it a lot. Knowing exactly where infinity focus is by feel is handy in the dark.
     
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  12. wjiang

    wjiang Mu-43 Hall of Famer

    Live View Boost in Custom Menu D (2nd page), combined with magnified view on a bright star.

    Another thing you can do is to look at the longitudinal chromatic aberration if you're getting any. If the green and purple fringes are in balance and minimised around the white star you know you've got the focus nailed. If green or purple dominates then you need to shift focus until they're balanced.
     
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  13. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Ooooh this is all brilliant advice...thank you!!! I'll try that tomorrow night! :)

    (By the way, I looked at the Roki, but it was just too big/too heavy for what I want it for)...definitely going to try the LCD boost, though and see how that works! :D
     
  14. Rasmus

    Rasmus Mu-43 Top Veteran

    661
    Nov 16, 2013
    Stockholm, Sweden.
    Or the Voigtländer 10.5mm/0.95...
     
  15. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    That's a great lens, no doubt, but it's an absolute BEAST by M4/3 standards. I travel a lot, so for me size/weight are huge considerations. A nearly 600g lens with a 72mm filter thread is unfortunately too big for my needs right now (maybe if/when I move back to Canada and settle down...).
     
  16. tkbslc

    tkbslc Mu-43 Hall of Famer

    If you are intending to primarily manual focus the 12mm f2, you might consider the Samyang/Rokinon 12mm f2. It's about half the price of the Olympus, too.
     
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  17. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Thanks, but no, I'm not planning on using it exclusively for that, and I'd like to stay with something small and light for travelling. :)
     
  18. tkbslc

    tkbslc Mu-43 Hall of Famer

    Well it's not exactly huge, but it is slightly larger than the 12mm f2 from Olympus - mainly the rim around the front of the lens.

    https://www.mu-43.com/showthread.php?t=63350
     
  19. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Hmm...verrrrry interesting! Thank you :)

    Napi's review is great, and so is this one...I wish that filter thread wasn't so massive (by M4/3 standards...most of my lenses are 52 or smaller...much smaller)...but hey...still not horrible...I love my Samyang/Roki/Bower fisheye, and this lens seems to be cut from the same cloth.

    http://petapixel.com/2014/06/04/review-rokinon-12mm-f2-0-great-option-astrophotogs-budget/