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7mm lenses that you would recommend?
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  • There were serious bugs in the Rectilinear Projection part of the script (it was defishing to Panini and the crop was totally off). So, this post is totally off: http://www.personal-view.com/talks/discussion/comment/68826#Comment_68826 because the Hugin project parameters are indeed different after all... There's a very distinct crop parameter on the second line.

    Anyway here's the right one.

    The comparison video is near complete but I need to put some text over it. I'll be uploading to youtube soon...

    defish.zip
    2K
  • @Duartix Please do! You had me into seriously considering buying one straight away.

  • @DirkVoorhoeve : Lightroom and some other RAW developers will correct lens distortions but I suspect they will not fully defish. And even if they do, the best you end up with is a Rectilinear projection which for the reasons already discussed is almost useless for a 180º fisheye. I've done quite a bit of research and Hugin was the best candidate around: it's cross platform, among it's 20 different projections it has got an Equirectangle Panini option, and best of all it's free!!!

    This guy here: http://m43photo.blogspot.pt/2012/03/defishing-fisheye-images.html has found a video processing app that does a Panini Projection. It's called kdenlive but I never heard of it and the last thing I need now is to learn another video processing tool and include it in my workflow. :(

    The way I figured it it's pretty simple and straightforward. You load your video in AE, export as image sequence, defish with my script, and reimport as image sequence.

    @RRRR Looking at the script lines that do the defishing ( http://www.personal-view.com/talks/discussion/comment/68826#Comment_68826 ), the hugin project file is amazingly simple:

    • p f16 w1920 h1080 v140 n"TIFF"

    • o w1920 h1080 f2 v140 y0 p0 r0 n"testfile.tif"

    • m i0

    where the 1st line f16 says it's Panini (f0 for Rectilinear), w1920 & h1080 is the size

    on the 2nd line I understand y0 p0 r0 must be yaw, pitch and roll, I don't know what f2 stands for

    on the 3rd line there is a i0 which I don't understand either

    My guess is that there is little if any parametrization for the Samyang, however it still works wonders... I really have to get some video results to post, you'd all be surprised at how good this gem of a lens really is!

  • @duartix that would be great, but are you sure there isn't any other way like lightroom, aperture or another app?

  • @duartix that would be awesome..

    If the settings are adaptable then one could easily make it work for other lenses as well..

  • (EDIT) Script updated here: http://www.personal-view.com/talks/discussion/comment/69869#Comment_69869

    Anyone besides @RRRR interested in having this script ported to a Java Application?

    Even though I've never built a Java app and it could take me weeks, I'm getting sick and tired of debugging batch shit and running circles around it's quirks and limitations...

    My plans are: an app that batch feeds JPEG/TIF/PNG files to Hugin and outputs defished images (image sequences) with proper logging, progress monitoring and configuration (instalation info, aspect ratios (detection even if possible), file naming) and anything that might come in handy.

    (EDIT) OUTdated batch defisher script included...

    defish.zip
    2K
  • @Duartix 20 minutes!? You have no idea how much I suck at this.. Even if I find instructions, it usually takes a lot of time to get something done in the terminal!

    Give me DOS! ;) Thanks though!

    Do you have any video examples with movement in the frame (like things crossing the frame) – I'd be very interested to see how it looks!

  • @duartix I use lenses 28mm or wider for over half of my work so my sense of "disturbing" is probably a bit altered. :)

    Anyway, you got me curious so I looked up some Panini materials. Here is one with more examples to supplement the links you already posted.

    http://vedutismo.net/Pannini/

    When it comes down to it, it's partially just a question of aesthetic preferences. I like the look of my favorite UWA lenses more than the Panini video examples I have seen so far. But that may be a question of examples.

  • If anything should happen to me in the very shorty term, the beast of a script that has grown from those lines is here. I got carried away again so it took some more developing, testing & debugging. I could add a few more stuff like execution time statistics and detecting the Hugin folder (right now you need to set that manually in the 4th line of the script), but I feel it's the moment for prime time.

    I'll include the script and document my findings with defished video in the proper thread, but right now it's up for everybody's use!

    So, change that 4th line of defish.bat, put it in a folder with unprocessed images from the GH2 and defish away!!!

    defish.zip
    2K
  • @thepalalias That instability you mention is another benefit of the Panini Projection. Since the distortion is a lot smaller than on a full rectilinear lens, it looks a lot less disturbing. Full rectilinear UWAs are disturbing lenses by nature, that's why their images cause so much impact. :)

  • The nice thing about using a lens like the Panasonic 7-14mm or a Canon 10-22mm (on an APS-C body) is the usable field of view available without having to do any post-processing.

    If you look at a lot of the stabilizer tests shot with a Panasonic 7-14 mm, you will notice that exaggerated distances/sizes towards the edges of the frame are a lot more noticeable than any barrel distortion. Notice how moving the camera forward and backward draws a lot less attention than panning left or right. This is especially noticeable with people in the frame.

    I have only used the 7-14mm once or twice but I have used the Canon 10-22mm on APS-C a lot at the 10mm end (16mm FOV compared to the 35mm equivalent). It is a LOT easier to use than a fisheye, at least if you aren't trying to make the effect of the lens really obvious. I have not had a chance to compare the barrel distortion on the two lenses, but the 7-14 should perform very well given the in-camera correction that the GH2 will automatically apply during recording.

  • AFAIK Hugin will run in a Mac. The absolute minimum for defishing a FullHD TIF file with Hugin is first to make a PANINI sub folder and then to create the following PANINI.pto file:

    • p f16 w1920 h1080 v140 n"TIFF"
    • o w1920 h1080 f2 v140 y0 p0 r0 n"testfile.tif"
    • m i0

    You can probably do that with the >> redirection operator in bash. Then you'll need to feed it to Hugin like this line does in DOS:

    • "C:\Program Files\Hugin\bin\nona.exe" -o panini/testfile.tif PANINI.pto

    Of course the path for nona.exe will also be different. Now I believe that if you spend 20m searching how to use a FOR loop in bash ( http://www.cyberciti.biz/faq/bash-loop-over-file/ ) you'll come up with a script that loops through a set of files in a folder. Now, don't forget to delete the .PTO file after each image defishing.

    No excuses @RRRR ;)

  • @duartix thanks! I don't know how I managed to miss that.. I'd be a whale on shore until someone manages to make it mac-able though. (At least until autumn when I plan to invest in a heavy editing station)

  • Not a 7 (8), but has anyone seen this posted? VEEERRRRRRY interesting...

    http://www.bhphotovideo.com/c/product/870935-REG/Samyang_SY8MV_N_8mm_f_3_8_Fisheye_Cine.html

  • @RRRR: You already have everything you need here: http://www.personal-view.com/talks/discussion/comment/66342#Comment_66342

    I've massively built upon that script though!!!

    It is now near complete with ~100 lines of batch code and what it does is ask for the image dimensions (4:3, 3:2, 16:9, FullHD or Auto), ask for the projection to be applied (Rectilinear or Panini), auto detect file types to be processed (JPEG, TIF or PNG) and finally clean up sources and conform generated file names in the end.

    It just needs another pair of hours of testing and tuning. I'll publish it soon if I don't get carried away on batch programming again...

  • From the Pentax you are well into 20+mm's of full frame equivalent.. So it's not that wide. With a wide angle converter it gets significantly softer.. The rainbow should fit, I don't recall Seb Farges altering it in any way.

    If you read Seb Farges comments then you can see that he had problems with focusing and internal dirt in his Rainbow copy, meaning it could well get sharper if you find a better one..

  • @duartix is your 7.5mm a Samyang? What brand/model is your 45mm 1.8? I looked at the link you posted, and the top-left (Rectilinear) image is closest to what I want to achieve. A slight distortion is okey, because that's how we humans view things - wide angle, while our brain slightly "distotrs/smudges" the edges because our attention is at the center. So which lens can I use to achieve that kind of top-left image with a GH13?

    @RRRR I don't mind using CCTV lenses. Actually, I have Fujian 35mm F1.7 and loving it. Also have a Pentax 8-48mm F1.0, which awaits modification as soon as I have a spare $125 - I'd be able to use it with GH13 in crop mode (albeit with significant loss of resolution), and it should give me a 32-192mm range. When I get a GH2, I heard I can use it without loss of resolution. I searched for Rainbow 3.5mm because that would give me exactly 14mm in crop mode. And I found this:

    I like the perspective look of Rainbow 3.5mm, but the texture is too soft. The modified Pentax 6mm gives a lot sharper image, which I like. Does Rainbow 3.5mm readily fit into a C-mount adapter, or does it need modification?

  • I know about width and distortion, but that is very interesting indeed.. Could you elaborate on your workflow to achieve that with video?

    (this could be interesting for correcting my SLR magic as well)

  • @RRRR That's the thing about using a Panini projection when defishing. The "Usable" part of the image is massively wider than with a Rectilinear projection. Here's an example at 120º: http://vedutismo.net/Pannini/FdeS-120x90.html

    The example won't tell you one very important thing though: the wider the original image is, the bigger the issue with distortion becomes. When going full Rectilinear, each corner pixel gets distorted to 5x-10x, while with the Panini projection it's more likely 1x-2x, which ends up holding quality and requiring a lot less cropping. The price to pay is distorted (non radial) horizontals. The horizontals that cross the center of the frame will still hold straight. In the end it's mostly a matter of careful composition that you'll soon master.

    I've only bought two lenses beyond kit: the 45mm F1.8 (a price/performance champ) and the 7.5mm as for other uses I've got plenty of legacy options. I can say that from a price/performance view, the Samyang is as good as the 45mm. It's really a no-brainer.

  • what about the tamron 4-12mm? its a c mount cctv of course so you have to use in ex tele mode but that makes it about 10mm wide angle abit fishy at widest but straightens up in u zoom in a tad.... it has its drawbacks but its very cheap if u can find one! and fun ! other than that old glass but the cheapest widest you will get is like 17mm tokina rmc or whatever its called (which isn't really that wide 30mm ish ....) theres also rainbow 3.5mm as mentioned (has to use ex tele again) or 6mm pentax which are c mount but more useable (focusing etc) but again ex tele and getting less wide.... then the samyang and see if u can straighten it. or the pansonic 7-14mm or olympus 9-18mm but they are abit slow and expensive. apart from that let me know if u find something else as im on the hunt too but feel its a fools errand! :D

  • @duartix It's pretty light, huh? ;) If you look at the "usable", not heavily distorted part of the de-fished image then I wouldn't say it's any wider. However, if distortions and loss of resolution is acceptable then it's obviously a lot wider.. Very good for it's price, nonetheless!

  • @RRRR & @kronstadt : The Samyang is worth it's weight in gold. I've got one about 1 month ago and I will never ever leave home without it.

    BTW it is much wider than the 7-14mm: http://m43photo.blogspot.pt/2012/04/defished-fisheye-compared-with-ultra.html

  • @kronstadt

    1. ultra wide angle lenses that are not cctv ones are not cheap. Cheapest (non cctv) you will find are cine c-mounts that you have to use in tele-crop mode, but they are not wide enough to get a pronounced wide angle IMO (and they go wider than any full format lens).

    2. There are ultra wide CCTV lenses that can be used in tele-crop mode. You have to trawl through e-bay on a daily basis and keep an eye out for a rainbow 3.5mm lens and possibly others that might work. However, I doubt you'll find any lens which goes as wide as the panny 7-14 zoom.

    Please let us know if you find anything!

  • For AviSynth users, this defish plugin might be interesting as well:

    http://forum.doom9.org/showthread.php?t=152860&highlight=defish

    Seems to work well when I work with 20mm/1.7 connected with 0.5 or 0.7 converter lenses.

  • @kronstadt: Panini projections from fisheye lenses are your best bet. Resolution will not suffer as bad as in a full rectilinear defish. BTW I seriously doubt you can get wide enough without going with CCTV lenses.