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07-01-2013, 08:52 AM - 1 Like   #16
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QuoteOriginally posted by drypenn Quote
I have exactly the same glasses (K55 and FA50), and exactly the same thought (apathetic to DA*55/1.4)
Same here. We should found a club/sect.


Last edited by causey; 05-04-2014 at 04:52 AM.
07-07-2013, 09:58 PM   #17
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Here are a few more that I took today in the park. Kind of a strange shot/framing. Goofy photographer issues aside, they were all taken within maybe 3 minutes of each other. I used the green button to meter again and you can see that wide open, the shutter speed once again were the same, but at same apertures as I stopped down, they metered slightly differently. Which is interesting to me. ISO was 100 for all of them. One of these times, under controlled circumstances, I'll force the shutter speeds to match at each aperture. The WB was the same on these also (shade), but look at the difference in the color of the water between the two lenses.

Anyway, comments welcome. I'm starting to get a sense of the character of each of these lenses.


K50@ f1.4 - 1/4000 and K55@ f1.8 - 1/4000







K50 @ f5.6 - 1/320 and K55 @ f5.6 - 1/400







K50 @ f8 - 1/60 and K55 @ f8 1/80



07-08-2013, 02:46 AM   #18
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QuoteOriginally posted by troika Quote
The WB was the same on these also (shade), but look at the difference in the color of the water between the two lenses.
The K50/1.4 is probably yellowed/browned, because of its radioactive elements.
07-18-2013, 06:25 PM   #19
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This is likely my last photos to this thread and possibly my last K50/1.4 photos. I took the shots with the 55 on the way to work yesterday morning and then started wondering how the DOF might have looked at 1.4, so I went back and took them this morning with the 50/1.4. This is in a Seattle coffee house and was there at the same time of the morning. The ISO is slightly different because I had changed a setting and something was wonky. So it's 160 for the 55/1.8 shots and 200 on the 50/1.4 shots. The 55 shots were at 1.8 and the 50 shots were at 1.4. Shutter speed was the same. So, even though it was consecutive days, I would expect the 55 exposure to be darker, both due to aperture and the slight ISO difference, but that's not evident. The DOF and rendering are maybe slightly different, but honestly guys, these two lenses and only very subtly different and I've decided to keep the 55/1.8. The 50 is listed for sale in the Marketplace.






I know that many of you have a better eye for this than I do. Can you see something that I can not here?

Thanks for indulging me on this thread. I learned from working through it and I learned from your comments. Maybe someone looking at one of these lenses in the future will find this thread useful some day too.


Last edited by troika; 07-19-2013 at 09:47 AM.
04-04-2014, 08:39 PM - 1 Like   #20
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Update on this thread. I still have both lenses. I listed the 50/1.4, but no one expressed interest in it. Hung onto it and have been shooting with it a lot more. Have repeated tests similar to the ones I've posted but I'll spare you all the comparative, staged photos, unless someone asks for them.

I'm thinking of parting with one of these lenses again, because they are just so similar, but now I'm actually a little more attached to the 50. They are almost the same lens, but I thought I'd document my journey further, since I've been sticking with both.

50/1.4 -
It is a partial stop faster. Not a big deal, but when you need it, it's nice to have it. This matters a lot more on film, when you can't just crank the ISO up and I have been shooting some film with it. Still, you've got to nail focus for it to be worth it.

As you stop down, the bokah balls stay rounder longer. They're not always round, as some of the photos earlier in the thread show, but it's a narrower range of the intermediate apertures where the geometrics show up in a noticeable way.

55/1.8 -
Feels a tiny bit better, smoother, better balanced on the camera. Nothing wrong with the build or feel of the 50, though. It's subjective hair splitting.

I slightly prefer the focal length. Just a little longer, more of a short tele feel. A step or two in either direction is the whole difference, but all things equal, I like it better. it might help the bokah as well. Hard to say.

Subjectively usually a little sharper at 1.8 than the 50 @ 1.4 or at least easier to nail focus with.

It will meter 1.8 about where the 50 meters f2. So, if you go by the green button, you get a little better exposure in low light at the same sutter speed on the 55 at that aperature. The difference in metering 1.4 on the 50 and 1.8 on the 55 is usually pretty small and sometimes non-existent. I'm not sure what to make of that, but they don't expose the same way. At any rate the difference on film is more important than on digital.

Places where it's a tie -
Wide open bokah is wonderful with both lenses. Something in the immediate foreground with a wall of busy stuff in the background, you're going to get a nice impressionist painting behind your subject with either lens at f2 or below.

Sharpness overall is pretty much a wash. I've done a bunch of pixil peeping back and forth and sometimes one seems sharper at some apertures, sometimes the other. They are effectively the same lens when it comes to contrast and sharpness of the focal point above f2.8. That's pixel peeping, looking at a photograph like a person looking at a photograph instead of a geek blogging about his lenses on the internet, it's tough to argue that there is any difference in sharpness of these lenses.

Results - I primarily use the lenses either walking around with the camera or photographing musicians in dark bars. I've gotten great results with both lenses and and also thrown away a roughly equal number of clinkers.

It may just be time to say "it's a tie". Both fine lenses, at the moment, I prefer the K50/1.4, but I didn't feel that way not so long ago and I might flip again. I might consider selling the 55 and sending the money with the K50 to Eric for a nice cleaning and alignment.

GREEN BUTTON - Something I've learned about my camera from all of this testing is that green button metering is inconstant. When I'm actually out photographing things with non-A lenses I use it to check in, but have better results finding a good result and then moving the shutter speed and/or ISO in full stops with the aperture setting to keep that exposure, checking my results and adjusting. Start over with the green button now and again or when the light changes, but it's not as reliable every shot like metering with a modern lens in a semi-automatic mode (TAv, Av, Sv, Tv) is.

Last edited by troika; 04-04-2014 at 08:46 PM.
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