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10-24-2012, 02:47 PM   #16
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Basically 18-24mm is about the "regular" wide angle range. Anything wider is more of an ultra-wide.

You mention seeing distortion in your pictures...what lens were you using? That would be a good starting point for us to recommend alternatives.

10-25-2012, 04:07 AM   #17
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The reason for the post is because landscape photography is something that I'd like to to get into and was curious as to where to start.I'd noticed some landscape photos with the bending effect and as I've discovered it's called 'barrel distortion'. So, I'm possibly looking at something in the 12-24mm range.

Can someone also explain the difference say between an 18-55 mm kit lens (as an example) and the regular 18-24 mm wide angle. I mean the 18-24 mm falls in the range of 18-55 mm? Do you see the same composition in your VF? Does this have anything to do with the 'Field of View' or 'Viewing Angle'?

Cheers Guys!
10-25-2012, 04:26 AM - 1 Like   #18
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QuoteOriginally posted by K5 Guy Quote
Can someone also explain the difference say between an 18-55 mm kit lens (as an example) and the regular 18-24 mm wide angle. I mean the 18-24 mm falls in the range of 18-55 mm? Do you see the same composition in your VF? Does this have anything to do with the 'Field of View' or 'Viewing Angle'?
A wide angle lens, like the FA 20/2.8,
would show you essentially the same composition in your viewfinder
as the kit 18-55 zoom set for 20mm focal length.
Both would then have the same 'Field of View' or 'Viewing Angle' as you say.

(As a thought-experiment,
cut a 24mm x 16mm rectangular hole in a piece of paper,
and hold the paper 20mm from your eye.
Looking through the hole,
you would then see what your viewfinder would show
with those lenses at 20mm focal length.)

The only minor differences might be different degrees of barrel distortion
(although in this example, both happen to be about the same, 2.5%).
10-25-2012, 08:16 AM - 1 Like   #19
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QuoteOriginally posted by K5 Guy Quote
Can someone also explain the difference say between an 18-55 mm kit lens (as an example) and the regular 18-24 mm wide angle. I mean the 18-24 mm falls in the range of 18-55 mm? Do you see the same composition in your VF? Does this have anything to do with the 'Field of View' or 'Viewing Angle'?
Think of yourself looking forward, with a circle drawn on the ground around you. If you were to draw an angle from yourself at the center of the circle, to the edge of the circle, to represent how much of the overall circle is in the picture, that's angle of view. For a wide angle lens, you've got more in the picture, and as you zoom in the angle of view gets smaller.

Angle of view is determined by the focal length of the lens, and the size of the sensor or film. On APS-C cameras, 24mm is the beginning of wide angle lenses.

So what I meant by 18-24mm range being "regular" wide angle is that the 18-24mm portion of your 18-55 lens is the part that's got a relatively wide angle of view. If you find yourself wanting something wider than 18mm, then you'd be getting into "super wide" territory.

Since you've got that 18-55 lens, the easiest thing to do to start with is go take pictures of landscapes at 18mm. If you find that you're not getting enough of the whole scene into the frame, that's when you would want to look at wider lens.

10-26-2012, 12:12 AM - 1 Like   #20
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QuoteOriginally posted by normhead Quote
My conclusion was Sigma 8-16, and the reason wasn't as much the lens quality, which was excellent, but the DA 15 ltd, I have to say, is unmatchable @ 5.6 for center sharpness, though it falls off at the edges, but at F8 it's excellent center and edge... to a degree I don't think you're going to match with any other lens. But the 8-16 has better control of CA. The DA 15 is no slouch, but the Sigma is outstanding for a lens of this focal length.
I've definitely got to have this DA15. For months I've been searching for second hand ones on Ebay, but there are none. Apparently it's really good; nobody seems to want to get rid of theirs.

They appear in the marketplace here though. But when I have to import a second hand copy into the EU, VAT and import duties gets added, and then I end up buying a used one for the price of a new one...

I found a hole in the market! I need to setup a website called "GreyBay".
10-26-2012, 02:37 AM - 1 Like   #21
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QuoteOriginally posted by K5 Guy Quote
The reason for the post is because landscape photography is something that I'd like to to get into and was curious as to where to start.I'd noticed some landscape photos with the bending effect and as I've discovered it's called 'barrel distortion'. So, I'm possibly looking at something in the 12-24mm range.

Can someone also explain the difference say between an 18-55 mm kit lens (as an example) and the regular 18-24 mm wide angle. I mean the 18-24 mm falls in the range of 18-55 mm? Do you see the same composition in your VF? Does this have anything to do with the 'Field of View' or 'Viewing Angle'?

Cheers Guys!
Hi K5 Guy - Have a look at Photo Zone ( Welcome to Photozone!) which will show where the distortions come in on various lenses. Zoom lenses are always a design compromise as you probably realise, but an 18 - 24mm design will be somewhat less of a compromise optically than the 18 - 55mm.
Some distortions you can remove automatically in post processing and the K-5 has a lens correction in the menu also (for Pentax lenses of course)
Personally I know what lens I would chose but then my choice may not suit your requirements...
10-26-2012, 08:04 AM - 1 Like   #22
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Morning,

Well I have gone down the wide angle route for quite some time, and have acquired glass along the way for specific reasons and quests. Professional landscape photographers usually wind up using 24,28 to near mid 35mm lenses due to the lack of distortion, as folks have talked about here already. What you are going to get by supplementing your 18-55 kit is not a different view, but higher image quality, resolution, better distortion control, maybe a faster aperture (to a degree), etc. be it at the associated cost. You can start helping yourself out by perhaps sorting your current shots from the kit lens by focal length (there is software to do this for you), and seeing what focal length has appealed to you the most. That would be a starting point.

In terms of "field of view", the lower you go in focal length, the wider each additional mm gets. That is the upside. The downside is that in order to obtain that additional mm, you are bending the light to get it on to the sensor, that bending brings with it additional distortion around the edges and boarders. Not a thing you can do about it, except to figure out how much - is too much for your taste.

So before I go on, let me add one comment here that I have not read yet. Your camera has a sensor of a fixed size (for the sake of argument lets say 4000 x 3000 pixels). As you walk through the focal lengths that you put in front of this fixed size sensor, each pixel will represent an area within the image. This pixel's representation of this area (which is length x height - 2 dimensions), will vary from a very wide angle lens to a more normal lens. As an example, the area represented by an individual pixel will have about 4x as much area at 8mm than at 30mm. Due to this, the more normal lenses are going to have a "sharper" quality to them, as opposed to a wider lens. This is something that folks don't consider, as in what goes into getting that wider field of view. Layered on top of this is the distortion issues of the focal length.

Originally I went with zooms for the versatility.
  • 10-17 Fisheye - is excellent - and one of my favorites. Great colors and rendering. Through composition, you can put the "bend" where you want it within the frame. Works very well on natural objects where the bend/distortion is not as obvious.
  • 8-16 - wonderful lens, great rendering and it is wiiiidddddeee - perhaps a bit too wide. Perspective control can be a problem if you put the subject tooo far towards the edge. Framing and composition is important. One thing I like is square rigged tall ships. With its 117 degree field of view, I can get the top of the mast to the waterline in one shot, relatively close in.
  • 12-24 - is also excellent and again one of my favorites. When in doubt - I use/take this as a single lens. Its not as wide as the 10-20s or 10-24s, but it has a wonderful balance between distortion control, great resolution. Sweet spot is about 18mm.
  • 16-45 - Again an excellent lens. Its going out of production, thus its price has been cut in half down to about $225 or so. Complements the 12-24 very well.
I have also acquired primes due their image quality. The zooms are great, however the primes coupled with their focal length are superb.
  • Zeiss 25/f2.8 ZK - Wonderful resolution, color and rendering. Very little distortion. Relatively fast at f2.8, and for me has an added close focus at 6 to 12 inches consumes 180 degrees of barrel turn of the 355 degree possible for focusing.
  • Contax Zeiss 28/f2.8 - I swapped mounts on this lens. Excellent, small and very light all manual, a poor man's 31 Ltd.
  • 31/f1.8 Limited - What everyone has ever said about the lens.
In essence, I have used the zooms for the very wide, and the primes for the low distortion standard landscapes.

Now one additional aspect to all of this. When you talk about wide angles, one unsaid aspect to all of this is foreground. With wide angle lens you get foreground, lots of it. Norm was talking about hanging off the edge of a cliff to get a shot. Well in this case I would think that the foreground was all the scene of the valley or gorge in front of him. Normally, you have stuff in front of you. The WA lenses will put it in to your frame, and you need to compose around it, or find something interesting to put into it. Just water or beach all the time becomes very boring. Another approach is to 1) crop it out (but you just paid a small fortune to buy the lens) or 2) shoot over it, with a longer focal length. Something like a 50, 85 or 135. Folks usually don't consider these as landscape focal lengths or lenses.

One more thing - stitching. You can stitch wide angle images together (including fisheye shots). I stitch wide angle shots together all the time to get both wider and deeper. That also goes for the not so wide focal lengths.

hope that helps....

10-26-2012, 12:16 PM - 1 Like   #23
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I'm sorry if this is a bit off topic, but are you sure you want an ultrawide angle for landscapes? I'm asking since I don't know how experienced you are with landscape and other photography (myself, I'm no expert but an amateur with a burning passion for taking pictures and I'm learning new things all the time...).

I have the 15mm ltd and I love it, but I don't use it for landscapes. It can be done, but it's difficult. With such a wide angle things at a far distance become so infinitely small that they almost disappear. I've found that you almost have to include objects in the close foreground to bring a sense of scale. I very much prefer longer lenses for landscapes, even long teles! I mostly use my 15mm for "fun" shots with distorted perspectives. And for indoor shots and architecture, or other situations when you're "crowded".

I'm not saying this to discourage you from getting an UWA. On the contrary, it's huge fun! (I want that Sigma 8-16 as well...)

10-26-2012, 12:54 PM - 1 Like   #24
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QuoteOriginally posted by K5 Guy Quote
The reason for the post is because landscape photography is something that I'd like to to get into and was curious as to where to start.I'd noticed some landscape photos with the bending effect and as I've discovered it's called 'barrel distortion'. So, I'm possibly looking at something in the 12-24mm range....Cheers Guys!
There is already a wealth of info on all the UWA (<<18mm) lens out there, so I won't bother with my 5c on these.

But I would like to throw in an alternative strategy altogether for landscapes, namely, stitching. You can then use almost any lens, and particularly lens with very low distortion. Several software produce will hand this with very little effort, and you get a benefit of real extra image resolution if you ever wich to print large formats. I use Hugin (freeware), but lots of others out there,

This for example is from a stitch into a 35Mpixel. About 20 images with large overlap, The distrotion is because this was an UWA lens:



And this pano stitched from a DA35 f/2.4 with no distortion. 7 images. Not landscale, but similar principle:

10-27-2012, 01:40 AM   #25
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Thank you everyone for your input into helping me make a decision! Next is funding, but I don't think I can start a thread about that!
10-27-2012, 07:13 PM   #26
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QuoteOriginally posted by K5 Guy Quote
The reason for the post is because landscape photography is something that I'd like to to get into and was curious as to where to start.I'd noticed some landscape photos with the bending effect and as I've discovered it's called 'barrel distortion'. So, I'm possibly looking at something in the 12-24mm range.
I think you're confused. Sure, some lenses have a small amout of barrel distortion, but that's not what you're seeing. Yu're seeing the *inevitable* effect of taking a wide scene and compressing it into a print or computer screen that is nowhere near as wide as the scene. This is called "perspective distorton" and it is not a lens defect. In fact, any lens that failed to produce this effect would be highly defective.

QuoteQuote:
Can someone also explain the difference say between an 18-55 mm kit lens (as an example) and the regular 18-24 mm wide angle.
What do you mean, "regular 18-24 wide angle"? I'm not aware of 18-24mm lens and would be surprised if one existed. Maybe you mean, what's the difference between the 18-24 portin of the range of two different lenses - the 18-55 and 12-24, say? Answer: nothing. All lenses when set to 18mm (assuming they include that focal length) produce exactly the width of image. The 12-24 is only wider that the 18-55 if you use the former in the 12-18 range.
10-27-2012, 07:50 PM   #27
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QuoteOriginally posted by pero Quote
I'm sorry if this is a bit off topic, but are you sure you want an ultrawide angle for landscapes? I'm asking since I don't know how experienced you are with landscape and other photography (myself, I'm no expert but an amateur with a burning passion for taking pictures and I'm learning new things all the time...).

I have the 15mm ltd and I love it, but I don't use it for landscapes. It can be done, but it's difficult. With such a wide angle things at a far distance become so infinitely small that they almost disappear. I've found that you almost have to include objects in the close foreground to bring a sense of scale. I very much prefer longer lenses for landscapes, even long teles! I mostly use my 15mm for "fun" shots with distorted perspectives. And for indoor shots and architecture, or other situations when you're "crowded".

I'm not saying this to discourage you from getting an UWA. On the contrary, it's huge fun! (I want that Sigma 8-16 as well...)
I find this sometimes to be the case, especially shooting with my 17-40 on my FF Canon (crop equiv of 11-26). It is so wide the landscape often gets swallowed on the wide end. It's better for landscapes that are closer (if that makes sense).

With that said, I have seen some stellar work from the DA15 on these forums. 12-24 too. You could also just upgrade the kit lens to a Sigma or Tamron 17-50 (Pentax 16-50 if you need the WR but the SDM issues scare me) for a bump in IQ for your normal zooming.
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