[Doundounba]

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I don't think anyone has mentioned the Venus Laowa 15mm F/4 Macro. Still 77mm filters, but well under 500g, full frame, and with interesting shift and macro abilities... No A contacts, but since there's not even an aperture lever, you can use Av mode (but not sure about TAv).

[peterh337]

I found the Sigma 15mm way cheaper here
Sigma 15mm F2.8 EX DG AF Diagonal Fisheye Lens | Microglobe | London | UK |

Looks too good - must be a grey import since SRS is £499.

[pres589]

There's walk-thru's on de-fishing using various software tools out there, just need to search, and maybe someone has a suggested path that they would like to share.

I wonder if someone like dcshooter here on the forum would be good to talk to about having an FA 20 cleaned up and de-hazed. If the coatings have been etched by the fungus, it's a problem, but if not... that said, I don't think I'd want to spend real money on a lens that may be junk due to fungus.

I don't think that Laowa 15 is really worth consideration per the desired traits like small, AF, et cetera.

[peterh337]

Yes; I googled for de-fishing and not only does a 15mm lens not need a huge amount of it (most of the stuff on the web is about correcting an 8mm lens, which is way worse, even if used on an APS-C and thus pre-cropped by 1.5x) but I have just checked and my Lightroom 6.5 has the correction for this exact lens, and it is variable.

I am going to buy one of these tomorrow. It looks like a decent modern-day lens with decent multi coatings.

Thank you all for your help

[Bui]

K18/3.5? (295g)

Phil.

Can we find this lens or the 20/4 easily now? I don't see them quite often. Do you know how does it/them compare to digital one like DA 15 or DA 21? 'Cause I'm looking for a wide lens for my K-x APSC.

[noelpolar]

Maybe you find some peace of mind in the fact that we Color Skopar 20 users are plagued with a 52mm filter thread, while you can nicely share filters between the M20/4, all all those wonderful M/A/F/FA/DA/D-FA primes with 49mm thread!

Can't tell you how baffled I was when my 49mm ND fell out of my the then new DA 50mm F/1.8 for no obvious reason! My currently 'active' 49mm selection includes HD-DA 15mm (crop), F 28/2.8, DA 35/2.4, F 50/1.7 or FA 50/1.4 or DA 50/1.8 (stepped down), D-FA 50/2.8, DA70/2.4 (soon replaced by 77/1.8), D-FA100/2.8WR, M135/3.5 (while the Carl Zeiss Jena is being repaired). All nice, compact, lightweight and most of them superb quality-wise. Thinking of making a non-protruding step-down ring to screw into the Voigtländer thread. A single slim 49mm filter will not cause vignetting for my use.

And no, I'm not looking to swap my little Voigtländer for anything else.[COLOR="Silver"]

You need a K30/2.8, K50/1.2 and K85/1.8 and then your 52mm Voigtlander will be in good company!

[gofour3]

Can we find this lens or the 20/4 easily now? I don't see them quite often. Do you know how does it/them compare to digital one like DA 15 or DA 21? 'Cause I'm looking for a wide lens for my K-x APSC.

They show up now and then, but compared to newer DA lenses the K18/3.5 or K20/4 are yes harder to find.

I don't have any lenses newer than FA, so can't comment on any DA's or APS-C. I only shoot film and all my UWA rectilinear lenses are excellent on FF film. (K15/3.5, K18/3.5, A20/2.8, K20/4, FA*24/2, K24/2.8 & K24/3.5)

Phil.

[peterh337]

Not sure if this one was mentioned before - Sigma 14mm f2.8

One on Ebay - expensive and this Italian seller is saying nothing about it
Pentax AF Sigma 14mm F2.8 Aspherical Come nuovo Fantastico con le Digitali | eBay

Review:
http://slrlensreview.com/web/reviews/sigma/sigma-wide-angle/148-sigma-14mm-f...sm-lens-review
It was last made in 2007. It is OK at smaller apertures, which is fine with a modern DSLR.
This one is rectilinear, does A and AF.
Too good to be true? Would it work with the K1?
The seller is arrogant, refusing to answer somebody's question about condition, saying it is offered as "used"!

So unless I am missing something it is a decision between that and the Sigma 15mm f2.8 fisheye (and de-fishing it)
Sigma 15mm F2.8 EX DG Diagonal Fisheye Lens Reviews - Sigma Lenses - Pentax Lens Review Database

[peterh337]

I got the Sigma 15mm f2.8 fisheye. A very nice lens, really well made.

Uncorrected


With the lens profile applied in LR 6.5


The 2nd pic had the highlights reduced a little. But this is just an illustration of what LR does when the lens profile is applied. It turns the fisheye into a rectilinear lens. Interesting! You can see the angle of view is reduced (obviously - you are applying pincushion, so have to crop) and my wild guess is a loss of about 10 degrees. so maybe that makes it a 17mm or so lens... still a good result given there are no modern 17mm lenses for the K1

As regards quality, I have put some files on dropbox but if I post the link, DB will pull my account due to the traffic. So if anyone is interested, drop me an email. The pics won't be copyright and can be rehosted anywhere.

On the above pic, zoomed in 100%, this is the centre (I used centre spot focus)

f2.8:


f5.6


f8


The left corner, for the three apertures respectively:







So, lots of chromatic abberation and generally poor, but this lens was £360 and e.g. the Pentax 15-30 is over £1000...

The CA is easily removed in LR





As regards flare, here the low winter sun is shining into the front lens element



This pic shows two roadsigns; one in the middle and one blue one to the right



Here they are 1:1, f5.6 (f2.8 is very similar)





again after the purple CA removed in LR. The two roadsigns should be about the same distance so there is a significant loss of sharpness to one side.

However much of that loss of sharpness is due to LR's pixel replication in the lens correction. This is the blue sign, 1:1, from the non-lens-corrected image

[peterh337]

I wonder if the above performance should be considered as normal?

[pres589]

Bumping this as I'd like to hear from folks more wise than I am.

[wissink]

I would probably take a few long walks trying my 15 Limited in crop to see what that felt like.

The DA 15 works reasonably well in 1:1 crop mode. You get a fair bit more than on full crop. Perhaps pair this with a bit of handheld pano work and you get decent results?

[pres589]

You could use it for pano's but can't think of a time I needed to do some pano stitching of photos taken with my DA 15 and K-5II. Width of field is supposed to be nigh on identical so, while not taking advantage of all that sensor in the K-1, at least it won't feel like a step backwards.

[pathdoc]

Agree about the size of the 15-30, I briefly tried one, I can't fault its IQ but the sheer size was off-putting and the lack of a filter thread meant I'd be needing to spend over £500 on a new holder and a basic set of filters.

Instead I acquired a Pentax 20mm f2.8 FA which seems to be very good on the K1, certainly enough for the limited amount of wide shoot I do, size comparison here:

It's things like this which make me think a wholesale re-release of the entire FA prime lineup from fisheye to short tele (135mm) wouldn't hurt one bit. If only the production restart logistics weren't such a hassle...

[peterh337]

One notable factor is that there doesn't appear to be a test / review anywhere of the 20mm FA
SMC Pentax-FA 20mm F2.8 Reviews - FA Prime Lenses - Pentax Lens Reviews & Lens Database
on a full frame DSLR.

The reviews are on APS-C cameras where it is a 30mm lens and anyway the perf will be great because one is not going anywhere near the corners.

As another data point, I dug out a photo (a 5000dpi scanned slide) taken with the 17mm Tokina, on an OM4 and some unknown film but possibly Provia 100 (was it around in 1999 - otherwise it would have been some other ISO64 E6 tranny film) and it is as sharp as the Sigma 15mm fisheye in the middle and way sharper than the Sigma in the extremes.