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06-03-2016, 06:36 PM   #1
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Sigma 30mm f1.4 vs FA31mm f1.8 for K-1.

I planned to sell my Sigma 30mm EX DC, and look forward to FA31mm ltd.
So, I tested Sigma on K-1, in crop mode and in FF, and found both modes useful.
FA 31 is a beauty, but sigma's bokeh is absolutely special, it's so smooth and "clean", even in situations when other great lenses will produce messy bokeh. I keep Sigma mostly because of its boheh.

Here are tests on K-1: crop mode, FF mode, and comparison of crop vs edited and cropped FF picture. I can use FF mode to get wider images, and I like that option.
So, what to do: to sell Sigma and get FA31 instead, or to keep Sigma and same money?

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06-03-2016, 08:54 PM - 1 Like   #2
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you already have the K1, if you keep your Sigma, you will have to shoot in crop mode, the FA31 is absolutely gorgeous when it comes to bokeh ! you can always try before buy (with the risk of buying on the spot) ^^
06-03-2016, 10:45 PM   #3
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I had a Sigma 30 1.4 and sold it to get the 31mm a couple of years ago.

The Sigma 30 1.4 was a great lens -- I liked the center sharpness and the speed.

The 31mm is worthy of all the praise it gets. It's expensive no doubt. I've been very impressed with it and can't wait to try it on the K-1. I think you can search for images shot on the K-1 and with the 31mm on here from a link on the home page.
06-04-2016, 02:42 AM   #4
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I certainly would strongly consider either a FA 31 or the Sigma 35 f1.4. Both are going to give better edge sharpness. The Sigma 30 is weak on the edges on crop, obviously sticking it on a K-1 doesn't give you any improvement. I like the FA 31's bokeh better than the Sigma 30 as well, for what it is worth. Transitions from in focus to out of focus are smoother.

06-04-2016, 03:05 AM   #5

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Get a Carl Zeiss Distagon T* 2/35 ZK . . . manual focus mind, but it's so easy to use.
06-04-2016, 03:25 AM - 1 Like   #6
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Another option would be the Sigma 35/1.4 that's actually made for fullframe. It's huge though.
06-04-2016, 05:05 AM   #7
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QuoteOriginally posted by starbase218 Quote
Another option would be the Sigma 35/1.4 that's actually made for fullframe. It's huge though.
I've had one for a fortnight and love it. More affordable than the FA 31mm. Yes it is big but not ridiculously so. Not sure I'd take it hiking if I was taking the 300mm as well but I have my FA43mm F1.9 as the lightweight but fabulous option.
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06-04-2016, 09:48 AM   #8
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Original Poster
Still thinking, got good points here.
I love FA31 starburst, it will make that lens universal, for night shooting as well.

I hate to let Sigma go, but probably it will be the right move to invest into FA31, the price it high however.
LBA gets pricey with the list of "wanted" for today:
Tamron 70-200
TC 1.4
FA31mm ltd.

Well, if I get FA31, I will sell DA 21mm ltd in addition... hate to do that as well.


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30mm, 30mm f1.4 vs, crop, dslr, f1.4 vs fa31mm, ff, full frame, full-frame, k-1, k1, mode, pentax k-1, sigma, sigma 30mm f1.4, vs fa31mm f1.8
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