From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1SVpM6-00067J-T5 for garchives@archives.gentoo.org; Sat, 19 May 2012 19:30:25 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 8D26AE060D; Sat, 19 May 2012 19:30:00 +0000 (UTC) Received: from mail-bk0-f53.google.com (mail-bk0-f53.google.com [209.85.214.53]) by pigeon.gentoo.org (Postfix) with ESMTP id 8F360E0913 for ; Sat, 19 May 2012 19:28:14 +0000 (UTC) Received: by bkcjk13 with SMTP id jk13so3539841bkc.40 for ; Sat, 19 May 2012 12:28:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; bh=HQGjg8eIrLdJvAa3NFd8hUrwp+syGyi/cik7+xHY7jY=; b=a04DDvkj2KEAA8ozmE9rfon/YRbX8LQoUf6e7V0LGvtdcc4cdj2aBd1ut3pYVvV5h4 DHtLoO5fd9yDNBL2AGJGK0tKd+7sX/yGvXxWk3ZDJpe1YbrgVu+/pRLdity5eUMa6e4r 197wTE97dOacBONMw3QwsQPv/uTcJeDKP3gfeVGEQT0S36m9bOJOfGJ1HQAw0rIW2xBD 1wZ4/7wlxFrCSYm/UCTDBe8ul1wm5Cf028riSlI5LmS1ylyn4IfWRBnGXysBPJn/7uan waOU4don25kc7/6ckCRGtCTTC9rlv3TB5OFWRCOidGr2gidc9iCF1ai3MD6Aer9XCPj5 Rp0w== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Received: by 10.204.129.87 with SMTP id n23mr5522268bks.19.1337455693553; Sat, 19 May 2012 12:28:13 -0700 (PDT) Received: by 10.204.42.207 with HTTP; Sat, 19 May 2012 12:28:13 -0700 (PDT) In-Reply-To: <20120519043828.GB2989@ca.inter.net> References: <20120510205232.GH3236@ca.inter.net> <4FAC389C.5020009@gmail.com> <20120511193120.GA2978@ca.inter.net> <4FADBC1B.3080004@gmail.com> <20120512132257.GA2968@ca.inter.net> <20120515025033.GB2969@ca.inter.net> <20120517043419.GC2965@ca.inter.net> <20120519043828.GB2989@ca.inter.net> Date: Sat, 19 May 2012 15:28:13 -0400 Message-ID: Subject: Re: [gentoo-user] merging or fitting images together From: Michael Mol To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Archives-Salt: 1cce3bab-de66-41a9-bbdf-20a468828f3b X-Archives-Hash: 911d10db0487da2c51b626c55a6d9d7d On Sat, May 19, 2012 at 12:38 AM, Philip Webb wrote: > 120518 Michael Mol wrote: >> Remarkably simple. Probably because I was only stitching two photos. > > -- details snipped -- > > Thanks : that gives me a 3rd method to pursue. > > NB in your result there are some badly curved lines : > bottom right, the front of the tram is badly distorted ; > centre top, the sides of buildings are curved outwards ; > also, the bottom of the photo has been lost, eg the L-side man's eyes, > & the result if smaller than the other =C2=A02 =C2=A0results achieved ear= lier. It's inevitable that you're going to lose some of the image. That's a function of reprojecting the stitched image. The distortions are very probably due to an incorrect focal length setting--something that's going to be impossible to get correct. But I likely could have corrected by forcing Hugin to treat it like lens aberrations, and getting it to correct for it that way. That would indeed take a great deal of time. > > No complaint at all ! -- but clearly all methods require some practice. The problem here is that there's missing source data. (Details below) > I've added your result to my I/net 'test' examples (I hope that's ok). np. I was going to share an ImageShack link, but I realized I wasn't sure whether by "keep the image off-list" you meant "don't attach the image" or "don't show the image on the list". > > Any other suggestions are welcome -- apparently this is of interest -- , > but I will turn to other priorities & investigate panoramas a bit later. > > BTW the location is Steelhouse Lane with Snow Hill Sta in the background > (I stated it incorrectly before) in May 1953 just before the final trams. > The photo was taken with a Zeiss Ikon camera, a well-reputed make : > perhaps you can find the focal width on the I/net somewhere. Now here's where the fun begins. According to Wikipedia, the Zeiss Ikon is 35mm SLR...but that's about all you're going to get from it. Really, everything else of interest is in the lens. Being an SLR, the lens can (and will) be swapped out by the photographer as circumstance demands. Each lens is going to have different aberration characteristics, but that's not nearly as important as the other difference: Without knowing the lens used, you know next to nothing about the focal length and field of view. (The two values can be derived from each other, as long as you know the frame size...which we do.) Worse, if the photographer was not using a prime lens[1], and was instead using a lens with variable zoom, you can't easily know what the real focal length was, as this will change depending on how far the photographer has zoomed in. Now, I suppose that if you knew the physical sizes of a couple fixed lines in each picture, where the two lines were some not-insignificant distance apart, you may be able to roughly calculate the focal length. But, really, without knowing the focal length, getting the stitch right is going to be guess-and-check. Incidentally, this is one reason why digital photography is awesome. Almost everything interesting you may need to know about the shot is going to get stored in the EXIF data in the image files. My camera stores the lens focal length at the time of snap; if I have a zoom lens on, it records the exact focal length the lens happened to be on. It's quite nice. :) [1] This isn't "prime" as "excellent" or "high grade"..."prime" in this context means it has a fixed focal length. It may have additional implications, but that's the largest functional relevance: a "prime lens" is a lens with a fixed focal length, a lens which doesn't have a variable zoom capability.[2] [2] I'm dribbling in a lot of semi-relevant technical stuff in here for those who are following the thread for informational purposes. --=20 :wq