1. Reminder: Please use our affiliate links for holiday shopping!

My new SEL20F28 pancake arrived - it is excellent!

Discussion in 'Sony Alpha E-Mount Lenses' started by Big G, May 11, 2013.

  1. Big G

    Big G TalkEmount Rookie

    13
    Apr 20, 2013
    Shame about Sony's QC - I had to return my first SEL20F28 pancake due to smudged "decentered" corners on the bottom of the frame at f/2.8. I suspected that the lens was just poor wide open, but I did not see any issues at the top of the frame so I returned the lens for a new one. The new one is excellent!

    Here's a couple of shots demonstrating (sorry about the boring subject matter). First is a 1500 pixel resize from a NEX-7 that I call my "A4 print" size as it is about the size of an A4 page on my 27" monitor. Red squares indicate crops:

    1500 pixel resize, f/2.8:

    _DSC2212.

    100% crop, frame edge, f/2.8

    edge.

    100% crop, extreme corner, f/2.8

    extreme.
     
  2. davect01

    davect01 Super Moderator

    Aug 20, 2011
    Fountain Hills, AZ
    Dave
    Enjoy!
     
  3. Big G

    Big G TalkEmount Rookie

    13
    Apr 20, 2013
    Some more test material. As usual, resized to 1500 pixels. Take it from me, it's a great lens.

    Wide open at f/2.8 again (look at the detail in the tree branches)

    _DSC2233.

    Centre at f/2.8:

    centre tree.

    Top edge at f/2.8:

    top edge tree.

    Bottom left corner at f/2.8:

    bottom left corner tree.
     
  4. addieleman

    addieleman Passionate amateur

    Nov 13, 2012
    Netherlands
    Ad Dieleman
    That doesn't look too bad although it seems that the bottom left corner is fairly unsharp. Can you show the top left corner? That will really reveal how good or bad this lens is because of the branches against the sky. In those cases I also test at f/8 because that's where I find the sweet spot to be for most lenses on my NEX-6.
     
  5. Big G

    Big G TalkEmount Rookie

    13
    Apr 20, 2013
    The bottom left of the image is probably too close for the DoF - remember that 20mm f/2.8 will only have a minimum acceptable sharpness at 3.76m (according to my DoF calc app) when focussing at 8m. I'd say my focal point here is greater than 8m here in the centre of the frame and thus the corners will be too close to be sharp. The top edge is much further away and therefore is sharper as it's in focus.

    This is not the type of shot you'd shoot at f/2.8 if corner to corner sharpness was required, you'd absolutely need to stop down.
     
  6. Big G

    Big G TalkEmount Rookie

    13
    Apr 20, 2013
    Top left extreme corner for reference:

    top left.
     
  7. addieleman

    addieleman Passionate amateur

    Nov 13, 2012
    Netherlands
    Ad Dieleman
    Thanks, that doesn't look too bad, better than expected and I suspect my Sigma 19/2.8 wouldn't be better.
     
  8. Amin Sabet

    Amin Sabet Administrator

    Aug 6, 2011
    I think most lenses from most manufacturers are at least a bit decentered. Your new copy looks to be a good one!
     
  9. Nexnut

    Nexnut TalkEmount Top Veteran

    This is not a shot I'd normally post but I'm still exploring my new (3rd) copy and that lens keeps surprising me.
    I was playing with my camera when my friend suddenly signaled she didn't like to be photographed but I couldn't resist and took a fast & dirty snapshot. The distance to her face is about 1,30 meters - NEX-7, 1/60sec, f2.8, RAW.

    The original frame (downsized):

    DSC09891-c2.

    100% crop (1100*1467px) - the focal separation at this distance and f2.8 and the microcontrast really amaze me. The 19mm Sigma is slightly sharper overall but this little pancake has a character of its own and I'll keep both lenses.

    DSC09891-NSh50.
     
    • Like Like x 1
  10. HabsFan

    HabsFan TalkEmount Veteran

    259
    Apr 10, 2013
    Ontario, CAN
    Yeah, this looks pretty good. I'm guessing your ISO was on the higher side here too.
     
  11. Nexnut

    Nexnut TalkEmount Top Veteran

    Nope, ISO125, but crappy light and the camera exposed for the highlights on the lower right.
     
  12. WNG

    WNG TalkEmount All-Pro

    Aug 12, 2014
    Arrid Zone-A, USA
    Will
    Quite good indeed for shooting wide open. Both samples from each poster.
     
  13. alaios

    alaios TalkEmount All-Pro

    Jan 11, 2013
    Düsseldorf
    Alex
    Hi, perhaps I am not the most expert.. but why the above results for a prime lens are considered good? I have read in many reviews (hmm how to right this kindly?) on how poor the SEL 16 and SEL 20 are ( I am a keen photozone fan). I mean I expect for a prime lens of 200 euros to giving you more. Why I should spent 200 euros for 1500 pixels resized shots (that even in that case results look poor to me).
    I find that both SEL 16 and SEL 20 can not really give you the potential of latest a6000 or even nex-7 sensor.
    That is my two cents. Perhaps people that have spent a life with lenses can comment more on my thoughts
    Alex
     
    • Agree Agree x 1
  14. Nexnut

    Nexnut TalkEmount Top Veteran

    It depends, Alex. I should have underlined the word 'character' in my post. I definitely didn't spend the 175€ for a 100% crop of an image that I've taken in poor light but rather for an optically 'acceptable' compact walkaround lens for my NEX-7 which - I have to conclude after 7 days with that lens - it isn't - I will sell it next week - more than 2 stops of vignetting is more than I'm willing to accept. I'm with you on photozone but numbers never tell the whole story. On top of that I generally prefer making my own experiences over consuming those of others. Regarding the resolution potential of Sony's 24MP APS-C models there are not that many lenses out there that get you suffiently close anyway, especially when it comes to wide glass.
     
  15. alaios

    alaios TalkEmount All-Pro

    Jan 11, 2013
    Düsseldorf
    Alex
    I could not agree more with your last sentence. I was expecting more from sony on their wide lenses. I have sold my SEL 16 and SEL 1855 since I did not feel happy with what I see and also read on forums. Currenty I am happy with what I have but that is another and weird story
     
  16. Nexnut

    Nexnut TalkEmount Top Veteran

    Well, I'm just back to Sony after 18 months with Fuji X. Terrific cameras, lenses and all but I didn't like that overpolished or -cooked X-Trans look, and their18mm isn't any better than the 19mm Sigma, my main walkaround lens - on the contrary. At the end of the day - what's the use of a fine lens if you're not happy with the files? I certainly wasn't and it took me some time to realize that. At the moment the old NEX-7 and my lenses, most of them Zeissies simply are the best compromise there is for my needs - no more, no less.
     
    • Like Like x 1
  17. davect01

    davect01 Super Moderator

    Aug 20, 2011
    Fountain Hills, AZ
    Dave
    While I would not call the 20mm stellar, it can result in some pretty nice shots.

    It is my preferred lens when going places where I know room is gonna be an issue. Plus it is tiny, a big plus when you want to be discrete.
     
  18. Nexnut

    Nexnut TalkEmount Top Veteran

    That's mainly what I got it for, Dave - a compact walkaround lens, but after one week and a got number of shots I have to realize that it can't hold a candle to my 19mm Sigma optically. About 2.5 stops of vignetting wide open is more than I'm willing to accept and I will sell it next week.