Author: | | Loyal Site Supporter Registered: November, 2017 Location: Minnesota Posts: 2,978 7 users found this helpful | Review Date: September 24, 2020 | Recommended | Price: $750.00
| Rating: 10 |
Pros: | really good wide open for astro | Cons: | expensive, even used | | This is a lens type that I have been looking to get for astrophotography for a while. My review and rating of this lens is focused on that aspect as everyone else have covered using this lens in more normal shooting conditions. So if you think this is a rather harsh review well astrophotography is rather harsh.
This lens now fills the spot that I had been trying to use my old S-M-C 17mm fisheye Takumar for in astrophotography. Unfortunately that old lens is at best terrible for astrophotography and really is unusable. Not having a usable UWA lens for astrophotography kind of shut me out a lot of interesting astro shots with things in the foreground or expansive skies so I had been looking for a while. So after debating what modern UWA to get I saw that one of the other forum members was selling his in basically unused condition and snapped it up for $750 and haven't regretted it.
So now onto how this lens performs for astro.
First if you are thinking a lens like this combined with astrotracer will be a good idea I will dispel that idea. There is only a very limited area of the sky where you can point this lens and not have astrotracer make a mess, even on APS-C. Basically you have to have it pointed at the celestial north or south pole or very close to it. The reason is how astrotracer functions and the huge area of the sky that this lens captures. So if you don't have it pointed at a celestial pole you will get a lot of error in the corners and along the edge and your shot will show lots or trailing away from the center. Using it on a properly aligned equatorial avoids this so if you have one you can get great tracked shots as the lens is so wide it will hide any alignment and tracking errors.
Good news is that you don't have to use the lens tracked as the short focal length will give good results using 200/(focal length) rule. On my first outing with this lens I ran 13s exposures for what ever stupid reason but should have been using 15s or 20s and I would have gotten better results. That was only my second time out with the lens and the first time out doing night shooting so I chalk that up to my stupidity. Since then I have done some more testing and you can run the lens at 20s without issue getting nice round stars. At 30s you will end up with ovals instead of dots for stars but then you are pushing things and that result is expected.
For astro one concern is always what f-stop do you need to run a lens at for it to produce acceptable or great results. Things to be on the lookout for are bloating of stars, blue halos, coma, and color fringing are the main ones. At f/2.8 this lens is a wonder, and I don't get bloated stars, halos, or color fringing. However at f/2.8 there is some coma along the edges and in the corners. It isn't bad coma and is better than what one would get from the D FA* 50/1.4 at f/2.8. Most people would not find the coma from this lens at f/2.8 to be a problem and I would be one of those. The coma is worse than my SMC A* 400mm F/2.8 ED [IF] at f/2.8 but it is only marginally worse.
To fully clean up the coma one needs to run this lens at f/4. When running it at f/4 this lens is perfect and I could not find any flaws in the test shots I took. Because the coma does not clean up sooner like it does with my SMC A* 400mm F/2.8 ED [IF] where it is gone at f/3.5. Given that this is a UWA lens becoming perfect at f/4 is still really good.
One feature of this lens that I didn't think would be as beneficial as it has proven to be is the low geometric distortion. I bring this up because if you want to stack and/or stitch shots it will make your life a lot easier and produce better results. These are very common things to do with astrophotography so it is worth mentioning. I have cleanly stacked over 100 images from this lens and not gotten trails or other stacking artefacts common from doing such things.
Since a picture can go along way here is one I created with this lens:
This image is the result of stacking 143 shots that were 13s each at ISO 3200 and wide open at f/2.8. There was a lot of processing to bring out as much of the detail as possible. The really bright bloated "star" is not a star but is Jupiter, to the left of it is Saturn and Mars is off on the right. Apart from being big objects in the sky there was a fair amount of dust in the air so the bloat comes from those planets illuminating the dust in the air like the moon does with light clouds. Because of the stacking process and the stars moving across the frame from shot to shot the stacking process actually ends up removing the little coma that was to be found in the image. I do regret not using 20s exposures as I wouldn't have had to push things as much in post so that would have improved the final image. Stacking was done in Sequator with the option to freeze the foreground and the sky using a complex foreground mask for the trees, horizon and barn.
| | | | | Pentaxian Registered: October, 2009 Location: North Posts: 4,704 4 users found this helpful | Review Date: May 24, 2020 | Recommended | Price: $1,000.00
| Rating: 10 |
Pros: | Smaller Size; low distortion; large image circle; | Cons: | Lens cover | Sharpness: 10
Aberrations: 10
Bokeh: 8
Handling: 10
Value: 10
Camera Used: K1
| | Note that the score of 10 for each category is with respect to UWA lenses and not to other focal lengths.
This lens is the widest UWA available for Pentax and yet, it is also the smallest.
Hence, its more portable than the other options.
Its also f2.8, so its versatile for that f2.8 hand held shot if necessary (in a museum or historical house where no tripod is allowed for example) or astro.
Build quality is all metal and excellent and being an A lens makes it easy to use.
Sharpness is as good as they come for UWA lenses.
Distortion is also the lowest available for a Pentax UWA.
Flare tolerance is one of the better ones vs the Samyang and Irix (w/ Irix being the worst )
In addition, its image circle IQ and low edge distortion makes it an excellent lens to use the Composition adjustment feature on the K1 w/o compromising much on IQ. IMGP996012019-2400 by pinholecam02, on Flickr IMGP046742020-1 by pinholecam02, on Flickr Pinang Peranakan Mansion -Ancestral temple by pinholecam02, on Flickr
| | | | Loyal Site Supporter Registered: March, 2009 Location: Cotati, California USA Posts: 4,460 3 users found this helpful | Review Date: May 1, 2019 | Recommended | Price: $900.00
| Rating: 9 |
Pros: | Super wide angle, very sharp | Cons: | Almost too wide, cheap lens cap | Camera Used: K-1II
| | This is a very well made, very very sharp ultra wide angle full frame lens. I've owned mine now for almost a year. My intent for it was landscapes and this it does very well. The fact that it's manual focus is no problem as most landscape work is shot at infinity anyway. I have tried it for close focusing shots and it's really hard to get a good focus which is why I marked it down a bit on handling. I've also lost the front lens cap (it just fell off down and 800 foot ledge) and it's hard to get a replacement for it. Try emailing Venus Optics on this if it happens to you.
While made of metal, it's really not too heavy, and it's small as well. The really issue/concern/something keep in mind is that on a full frame camera, it's v e r y w i d e. I have found this is a limiting issue with it. I also own the DFA 15-30 which, if you want one wide angle lens for the K-1, that the one to get IMHO as it really is more versatile for a lot of situations. The lens does flare a bit when the sun is nearly in frame but I find that it's more controlled than one might expect for an UWA lens.
Bottom line for me is that this has a permanent place in my camera bag when I want or need wide shots.
Here are a couple of images I've produced with this lens. _IMG2448 by Tim Morgan, on Flickr _IMG4857_8_9 by Tim Morgan, on Flickr
| | | | Loyal Site Supporter Registered: August, 2010 Location: Massachusetts Posts: 58,951 4 users found this helpful | Review Date: January 4, 2018 | Recommended | Price: None indicated
| Rating: 9 |
Pros: | Significantly more compact than Pentax 15~30mm and Irix 15mm f2.4 | Cons: | Inevitable WA convergence when tilted up or down | | I had a Pentax 15~30mm for a few days, but returned it because the size & weight meant I would never take it with me. I had an Irix 15mm f2.4 (Firefly) but it was too bulky, hard to fit into even my backpack. I sold the Irix shortly after purchasing this 12mm. This Venus/Laowa is significantly more compact = a reasonable fit into my camera bags. It's heavy, but much easier to take along than either the Pentax zoom or the Irix and the FOV is MUCH wider. The resolution is excellent, far superior especially at the edges to a Sigma 12-24mm I was using for a while on my K1 (I found a leftover new one on EBAY from a camera store in Canada). There is WA style convergence when the lens is tilted up or down but that cannot be avoided with any UWA. The coverage is so expansive that much or all the convergence can be removed in PP without losing significant parts of an image, if such parallel-line images are desired. This is a really good choice for a FF ultrawide and deserves very serious consideration by anyone in the market for such a lens.
| | | | | Pentaxian Registered: December, 2011 Posts: 3,112 12 users found this helpful | Review Date: December 6, 2016 | Recommended | Price: $799.00
| Rating: 10 |
Pros: | field of view, compactness/portability, sharpness | Cons: | | Sharpness: 9
Aberrations: 9
Bokeh: 6
Handling: 10
Value: 10
Camera Used: Pentax K-1
| | Overall the best ultrawideangle lens I have seen so far.
What is it for: - One shot panoramic landscapes
- indoor architecture, rooms, cathedrals etc.
The one thing I love most is the portability. This 12mm F2.8 lens is easier to pack and smaller than the crop Sigma 8-16 which only offers an equivalent aperture of F6.3.
Most UWAs are just to clunky to find their way into the bag regularly.
The distortion is already minor and once you create your own lens correction profile it is completely gone.
The build quality is outstanding and on par with the old takumar, K series, Zeiss level. Evene the detachable hood is made out of solid metal.
The lens sports a fully working A setting, so is easy to use.
Best sharpness overall can be achieved at F8. Best DoF when focused at somewhere between infitity and the 3 m setting.
With wider apertures the extreme corners (usually noticed on the lower edge) get more soft (as with all UWAs).
Wide open there also is some minor softness in a ring (not the extreme edges or the center). All this is only noticeable when pixelpeeping or using large prints.
Definitely recommended.
Proof:
A statement on portability (you can also see the A setting on the aperture ring in PK):
Full res sample: Rheinturm in 12mm by Karl Knipser, auf Flickr | | |