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04-18-2012, 10:51 AM   #1
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Which Fisheye (if any) is best for turning into a wide angle using software?

I've been looking into wide angle lenses and they are way too expensive for my budget. I'm into sharpness and quality at around 20mm or lower, but because of my budget (preferably £100-£200) I suppose I'll have to compromise. Would it be sensible to buy a fisheye lens and use software to de-fish it? If so, what would the best lens at this budget to go for, considering I don't actually have much interest in using a fish-eye for fishy purposes?

I have a Miranda MC 28mm 2.8, which I am unhappy with - the pictures are just too naff compared to my SMC 50mm 1.4 and find myself going insane having to compromise on quality when room is too tight. I also have the kit 18-55 that came with my Samsung GX-10, which isn't too bad but I want better.

Do you think a de-fished fisheye would produce better results than using those lenses (which don't need de-fishing)?

I'm not into extensive post processing generally speaking, but would be happy if the software is simple enough, especially if the fisheye was a prime and I could therefore fix the settings in the de-fishing software to work accurately every time.

Thanks in advance!

04-18-2012, 11:07 AM   #2
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Honestly, you might be better off image quality-wise stitching photos taken with a quality lens than you would defishing a fisheye shot. The stretching of pixels at the edges of the picture can be extremely degrading to overall picture quality.

It all depends on what you're shooting and if you can keep the horizon centered in the frame. And if there are strong verticals in the frame. And, and, and… you get the point.

Buying a fisheye looking toward specifically defishing it is a false economy IMO.
04-18-2012, 12:08 PM   #3
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21mm DA limited seems to go on ebay for about £300 or thereabouts. Above your £200 budget but by no means unaffordable. I'd suggest saving for a couple of months and getting something really good. It's a lot cheaper in the long run than buying something that's not and then getting the thing you actually wanted in the first place six months down the line. Buy right or buy twice.

Kit lens isn't up to scratch? Gotta be better than a defished image. Tammy 17-50 can be picked up for a couple of hundred quid or not too much more.

Just out of interest, what fisheye were you contemplating? They don't generally fall in the price range you mentioned.
04-18-2012, 12:09 PM   #4
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Did you check out the Samyang 14mm? There are a few other names, but I think Samyang is the manufacturer. If you need further persuasion (other than the price), you can visit Photozone.

04-18-2012, 12:37 PM   #5
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de fished fisheye will be worse than your 18-55mm in most cases

Samyang 14mm is probably your best bet
04-18-2012, 01:57 PM   #6
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QuoteOriginally posted by jezza323 Quote
de fished fisheye will be worse than your 18-55mm in most cases

Samyang 14mm is probably your best bet
This is an excellent lens. If it's too expensive, I suggest the previous idea: stitch images together. Most old ultrawides do not work well with digital sensors.

I also recommend the Sigma 8-16. It's not cheap, but it is way wide and produces great IQ.
04-18-2012, 02:43 PM   #7
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QuoteOriginally posted by bimjo Quote
Honestly, you might be better off image quality-wise stitching photos taken with a quality lens than you would defishing a fisheye shot.
I use Microsoft ICE to stitch photos; it's pretty easy. That said, I own a DA15 now
04-18-2012, 06:12 PM   #8
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Echoing some of the previous advice: Defished images usually suck. That's because defishing stretches the image edges, killing resolution outside the central area. If I defish a 16mm image (from my DA10-17 or the Zenitar 16/2.8) I need to downsample it, shrink it by 1/3 in each dimension. So a shot of around 4500x3000px emerges as about 3000x2000px, going from 14mpx to 6mpx on my K20D. Defishing a 10mm image is even worse. These are fine for Facebook thumbnails, not so fine for much else.

That said, you can get very nice (and sharp) images from the Zenitar 16/2.8, which usually goes here for around US$200. (Cheaper in Europe, I'm told.) It can be just slightly fishy on an APS-C camera. Depending on how it's used, its fishiness can be mini- or maxi-mized. But it's not rectilinear and never will be. If you want straight lines at the image edges, too bad.

So, your options:

* Shoot sequences and stitch them together into panos. A 28mm lens is ideal for this; every wider lens I've tried shows some edge distortion.
* Use a wide-angle adapter. Better yet, don't. They almost all suck terribly. They're OK for video, lousy for still. Forget I mentioned this.
* Bite the bullet and buy a UWA lens. I recommend the Tamron 10-24 for various reasons. I haven't tried the Samyang 14mm.

Hay, it's only money. Good luck!

04-18-2012, 08:39 PM   #9
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QuoteOriginally posted by PentaxLearner Quote
I've been looking into wide angle lenses and they are way too expensive for my budget. I'm into sharpness and quality at around 20mm or lower, but because of my budget (preferably £100-£200) I suppose I'll have to compromise. Would it be sensible to buy a fisheye lens and use software to de-fish it? If so, what would the best lens at this budget to go for, considering I don't actually have much interest in using a fish-eye for fishy purposes?

I have a Miranda MC 28mm 2.8, which I am unhappy with - the pictures are just too naff compared to my SMC 50mm 1.4 and find myself going insane having to compromise on quality when room is too tight. I also have the kit 18-55 that came with my Samsung GX-10, which isn't too bad but I want better.

Do you think a de-fished fisheye would produce better results than using those lenses (which don't need de-fishing)?

I'm not into extensive post processing generally speaking, but would be happy if the software is simple enough, especially if the fisheye was a prime and I could therefore fix the settings in the de-fishing software to work accurately every time.

Thanks in advance!

Not sure if anyone has suggested it yet, but if you can only have one lens, a diagonally corrected ultra wide angle is a better option than a fisheye. As with a fisheye, every photo is a fisheye curve, and thats not always a good thing, and its a lot of work to de-fish a pic, with an ultra wide, you can just take photos al day long, and if the subject is such that a fisheye would look good, its much easier to put a fisheye effect to that picture.

food for thought.

cmohr
04-19-2012, 12:31 AM   #10
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QuoteOriginally posted by cmohr Quote
Not sure if anyone has suggested it yet, but if you can only have one lens, a diagonally corrected ultra wide angle is a better option than a fisheye. As with a fisheye, every photo is a fisheye curve, and thats not always a good thing, and its a lot of work to de-fish a pic, with an ultra wide, you can just take photos al day long, and if the subject is such that a fisheye would look good, its much easier to put a fisheye effect to that picture.
What a strange idea! A fisheye has a much wider field of view than a rectilinear of the same focal length. For a 10mm focal length on an APS-C DSLR, a rectilinear lens has a diagonal FOV of 110 degrees, while a circular fisheye is around 180 degrees...

"Defishing" an image is not complicated and yields excellent results if you use a good lens. The angles are indeed a bit soft because of the pixels stretching, but this is the case anyway with many superwide lenses.

In my experience, a fisheye lens is much more versatile than a superwide, as it is very easy to go from a circular perspective image to a rectangular one without much quality loss and while keeping a very wide field of view. On the contrary, converting an image taken with a rectilinear superwide into a circular perspective one is not going to make the field of view any wider!

Here are three pictures taken at 10mm (taken by Mock and intially published on this thread).

First, the original image taken with the Pentax DA 10-17 at 10mm:



2. Then the same image once "defished" with PTLens:



3. And the image taken with the rectilinear Sigma 10-20 at 10mm:



It is evident than you can go easily from 1 to to 2 (by defishing) then from 2 to 3 (by cropping), but there is no way you can go from 3 to 2 or from 3 to 1! You could of course use tiling to assemble two pictures or more, but to me it is much easier to shoot and process a single picture than to have to shoot and process many pictures...

Cheers!

Abbazz

Last edited by Abbazz; 04-19-2012 at 02:02 AM.
04-19-2012, 03:39 PM   #11
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QuoteOriginally posted by Abbazz Quote
What a strange idea! A fisheye has a much wider field of view than a rectilinear of the same focal length. For a 10mm focal length on an APS-C DSLR, a rectilinear lens has a diagonal FOV of 110 degrees, while a circular fisheye is around 180 degrees...

"Defishing" an image is not complicated and yields excellent results if you use a good lens. The angles are indeed a bit soft because of the pixels stretching, but this is the case anyway with many superwide lenses.

In my experience, a fisheye lens is much more versatile than a superwide, as it is very easy to go from a circular perspective image to a rectangular one without much quality loss and while keeping a very wide field of view. On the contrary, converting an image taken with a rectilinear superwide into a circular perspective one is not going to make the field of view any wider!

Here are three pictures taken at 10mm (taken by Mock and intially published on this thread).

First, the original image taken with the Pentax DA 10-17 at 10mm:



2. Then the same image once "defished" with PTLens:



3. And the image taken with the rectilinear Sigma 10-20 at 10mm:



It is evident than you can go easily from 1 to to 2 (by defishing) then from 2 to 3 (by cropping), but there is no way you can go from 3 to 2 or from 3 to 1! You could of course use tiling to assemble two pictures or more, but to me it is much easier to shoot and process a single picture than to have to shoot and process many pictures...

Cheers!

Abbazz
Thats what I'm saying, the OP is wanting rectiliner wide angle photos, defishing every photo you take will become very teadious indeed.

Just read the PO's again, for 100-200 pounds you'll get a good sharp tak or pentax 20mm if you loook.

Here one on fleabay at the moment sitting at 200.00 AUS at the moment

SMC Pentax-A 20mm F2.8 In Used Excellent Condition | eBay
04-19-2012, 10:48 PM - 1 Like   #12
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QuoteOriginally posted by bimjo Quote
The stretching of pixels at the edges of the picture can be extremely degrading to overall picture quality.

It all depends on what you're shooting and if you can keep the horizon centered in the frame. And if there are strong verticals in the frame. And, and, and… you get the point.

Buying a fisheye looking toward specifically defishing it is a false economy IMO.
Lots of opinions on this thread, but this one is close to my opinion. I use a KMZ MC Zenitar 16/2.8 Fisheye (originally designed for 35mm film) and have seldom have the need or desire to de-fish a shot when used on my K10D. I use is as a general purpose wide-angle on that camera and find that you really have to work with that camera to get an unnatural-looking result.

Much depends on the orientation of straight lines to the lens axis. Tilt the camera up or down and the horizon goes wonky. Frame the photo so the horizon is not present and things look fine. Here is a link to fisheye shots on my Flickr account:
fotostevia: Zenitar on Flickr
And a few from the car show to show you what can be done:





...and a landscape that doesn't look fishy at all even though the camera is tilted up relative to the horizon!




Steve

(...loves his zen...)

(...also wants to point out that the curving of lines is not distortion...quite the opposite, actually. Rectilinear ultra wides have terrible volumetric distortion at the margins...)
04-19-2012, 11:12 PM   #13
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QuoteOriginally posted by stevebrot Quote
Lots of opinions on this thread, but this one is close to my opinion. I use a KMZ MC Zenitar 16/2.8 Fisheye (originally designed for 35mm film) and have seldom have the need or desire to de-fish a shot when used on my K10D. I use is as a general purpose wide-angle on that camera and find that you really have to work with that camera to get an unnatural-looking result.
[...]
Steve

(...loves his zen...)

(...also wants to point out that the curving of lines is not distortion...quite the opposite, actually. Rectilinear ultra wides have terrible volumetric distortion at the margins...)
Good shots, good statement. This is exactly the kind of stuff the Zen, and the DA10-17 at the long end, do well. And the Zen is 2.3 stops faster there. That helps in dimness.

We just must beware of straight lines. I can't use a fisheye in my Sierra Nevada conifer forest -- all those trees are falling on me! Exception: I can shoot down at tree stumps covered with fungi or boulders crusted with lichen. No bent lines there! But keep me away from straight lines. Although intersecting lines have great possibilities...

Yeah, fisheyes actually lack distortion, projecting a round universe onto a flat frame pretty accurately, much more so than edge-stretching rectilinears. We've just been trained to see FE images as crazy. Go figure.

--Rio(luvs his Zen too)Rico
04-19-2012, 11:25 PM   #14
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QuoteOriginally posted by stevebrot Quote
And a few from the car show to show you what can be done:
My Zenitar comes with me to every car show, it is my favorite for shooting cars because you can exaggerate shapes and curves without looking too extreme. A 50mm f1.4 is also in my car show kit for detail shots, sometimes I'll take a my 35mm f2.8 or 21mm f3.8 Tokina made lenses too, but the 16mm and 50mm get the most usage by far.
04-20-2012, 12:34 AM   #15
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QuoteOriginally posted by cmohr Quote
Thats what I'm saying, the OP is wanting rectiliner wide angle photos, defishing every photo you take will become very teadious indeed.

Just read the PO's again, for 100-200 pounds you'll get a good sharp tak or pentax 20mm if you loook.

Here one on fleabay at the moment sitting at 200.00 AUS at the moment

SMC Pentax-A 20mm F2.8 In Used Excellent Condition | eBay
The original poster wants a budget lens to go wide and is leaning towards a fisheye. I think looking for a fisheye makes perfect sense, as good rectilinear wides are quite expensive. The Pentax A 20mm you are linking to is already $210 with three days to go, and it will surely fetch much more than that. A Zenitar 16mm would be much cheaper, while offering a wider field of view. The fisheye effect is not very pronounced with a Zenitar on an APS-C DSLR, and many pictures won't need any defishing at all.

I agree with SteveBrot and RioRico when they state that a fisheye is better used as a fisheye. To my eye, circular perspective images from fisheyes are much more natural than images from rectilinear superwides. I really don't like those stretched corners!

But it is also true that from time to time we need pictures with straight lines Defishing pictures taken with a Zenitar is a fast and painless operation. You can work in batch on entire directories quite effortlessly. And you'll get high quality images after defishing and cropping, with a field of view equivalent to a rectilinear 14mm lens, for only a fraction of the cost!

Cheers!

Abbazz
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