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Nikkor 50mm f/1.2 sometimes confuses Autopano Pro 2.0.2

PostPosted: Tue Jun 09, 2009 3:40 pm
by MJSfoto1956
I'm seriously considering purchasing APP as it is clearly a great product, but I've had some trouble creating panos from my test shots and I'm hoping someone can chime in here to assist.

In particular, APP seems to get confused by my (old) Nikkor 50mm f/1.2 AIS lens, thinking it is a fisheye. Now the wierd part is this: if I have a single row pano with too much overlap, APP makes a mess of things (how about a row of overlapping, perfectly circular images!!!!). But if the overlap is just right (say 30% or so), then all is usually well. Interestingly, this only applies to single row panos, especially in horizontal format. I've yet to see this behavior in any multi-row for which APP seems ideally suited.

Just so I don't waste anyone's time: in multi-row, APP is saying I typically have RMS of 1.8-2.5, so my panohead is adjusted *precisely*.

As a side note: the same single row panos that APP is having trouble with are not an issue for PTGui, which stitches them perfectly.

Finally, the behavior of APP is different depending upon whether or not I first process the images through DxO Optics Pro (from yet another French software firm). To generalize a bit: the new 2.0.2 version of APP seems more sensitive to single-row images processed by DxO than the previous 2.0 version. The proof of this is the following: a single row of N images converted manually from .NEF format to .TIF using ACR gets formatted one way by APP. The exact same images processed by DxO to .TIF gets processed significantly differently (usually for the worse). What gives here?

Any insight would be appreciated!

Michael

PostPosted: Tue Jun 09, 2009 3:51 pm
by mediavets
Michael,

Welcome to the forum.

1. Too much overlap is probably resulting in spurious superfluous links between non-neighbouring images. You can use the Control points Editor to remove these. Or it may be down to the scene which may have repateting lemenst which confuse the CP detection algorithm.

See: http://www.autopano.net/wiki-en/action/view/Manual_stitching_of_panoramas


2. Converting images from one format to another may be stripping out the EXIF data used by APP?

PostPosted: Tue Jun 09, 2009 4:24 pm
by AlexandreJ
This may clearly be an exif issue. DxO is a known exif killer, so let's check the exif of your images first.
BTW : Ais lens doesn't transfer any exif data to the camera body. I'm wondering what value you have in original nef file ...

PostPosted: Tue Jun 09, 2009 7:16 pm
by bpmhutch
DXO tends to make APP think the images are fisheye when they are not. Check when you initially open them and change if need be works for me!

Pete

PostPosted: Tue Jun 09, 2009 7:37 pm
by MJSfoto1956
The pro-level Nikons allow you to "add" lenses to their memory "banks" -- in this way, I can use old manual-focus lenses and still get auto-exposure and auto-flash in Aperture-priority mode.

on a D200-generated .NEF this is what I see using Adobe Bridge:

Camera Data (EXIF)
[ul]
[uli]Exposure Mode: Manual[/uli]
[uli]Focal Length: 50.0mm[/uli]
[uli]Length in 35mm Film: 75.0mm[/uli]
[uli]Lens: 0.0 mm f/0.0[/uli]
[uli]Max Aperture Value: f/1.0[/uli]
[uli]Flash: Did not fire[/uli]
[uli]Metering Mode: Pattern[/uli]
[uli]Custom Rendered: Normal Process[/uli]
[uli]White Balance: Auto[/uli]
[uli]Digital Zoom Ration: 100%[/uli]
[uli]Scene Capture Type: Standard[/uli]
[uli]Gain Contol: 0[/uli]
[uli]Saturation: 0[/uli]
[uli]Sensing Method: One-chip sensor[/uli]
[uli]File Source: Digital Camera[/uli]
[/ul]

on a DxO-generated .TIF (from the above .NEF) this is what I see using Adobe Bridge:

Camera Data (EXIF)
[ul]
[uli]Exposure Mode: Manual[/uli]
[uli]Focal Length: 50.0mm[/uli]
[uli]Length in 35mm Film: 75.0mm[/uli]
[uli]Max Aperture Value: f/1.0[/uli]
[uli]Flash: Did not fire[/uli]
[uli]Metering Mode: Pattern[/uli]
[uli]Subject Distance: 0.0m[/uli]
[uli]Custom Rendered: Normal Process[/uli]
[uli]White Balance: Auto[/uli]
[uli]Digital Zoom Ration: 100%[/uli]
[uli]Scene Capture Type: Standard[/uli]
[uli]Gain Contol: 0[/uli]
[uli]Contrast: 0[/uli]
[uli]Saturation: 0[/uli]
[uli]Sharpness: Normal[/uli]
[uli]File Source: Digital Camera[/uli]
[/ul]

As you can see, Dxo deletes a few items and adds in a few new items. One could assume that APP "does different things depending upon differences in the EXIF data" but in the case above, that still does not explain the "fisheye" assignment by APP nor the differences in output rendering presumably attributable to any combination of the following:

Missing Lens vs. Lens = 0.0mm
Missing Sensing Method vs. Sensing Method = One-chip sensor
Missing Subject Distance vs. Subject Distance = 0.0m
Missing Contrast vs. Contrast = 0

Makes me want to go out and try a "modern" Nikkor lens just to see if behaves any differently!

Michael

PostPosted: Wed Jun 10, 2009 9:09 am
by AlexandreJ
This is definitively a good candidate image to upload to our ftp so we could check ourself.
http://www.autopano.net/forum/t766-ftp-server

PostPosted: Thu Jun 11, 2009 3:56 am
by MJSfoto1956
files uploaded to your ftp site... (MJSfoto1956.zip)

Michael

PostPosted: Sun Jun 14, 2009 11:36 pm
by MJSfoto1956
So I tried another simple test out the window to my back yard.

3x3 matrix shot with the 50mm f/1.2 (bracketed)

vs.

the same images processed via DxO.

Here is the screenshot showing how distorted the DxO stitch is:

Image

Question: is there a way I can batch process the DxO images to "add back in" what APP is looking for?

Michael

PostPosted: Mon Jun 15, 2009 9:39 pm
by MJSfoto1956
On a lark, I tried to see what would happen if I specified PNG as the DxO output rather than JPG -- and sure enough, the stitch is BETTER than the original NEFs!

here is a screenshot:

Image

So the upshot seems to be that APP doesn't like JPGs from DxO but is totally "happy" with PNGs -- anyone have a clue as to why this could be so?

Michael

PostPosted: Mon Jun 15, 2009 10:39 pm
by DrSlony
Your lens got detected as fisheye in most panos.

PostPosted: Tue Jun 16, 2009 2:00 am
by MJSfoto1956
that's because Nikon doesn't put the information that APP is looking for when you use an "older" manual focus lens -- even though the camera will autoexpose and even autoflash properly. There *IS* EXIF data that APP could use, but they are not looking for it the way Nikon describes it. Instead, it appears APP is really only "happy" if you either:

A.) use an AF (modern) lens, or
B.) convert the .NEF file using DxO to .PNG. Under these conditions APP detects a "normal" lens and does the right thing

Michael

PostPosted: Tue Jun 16, 2009 3:05 am
by DrSlony
So this is a bug that Autopano needs fixed, but developing your RAWs before processing is something you should do anyway. Either save as PNG, or save as TIFF and use ExifTool GUI or Exiv2 to remove the EXIF.

PostPosted: Tue Jun 16, 2009 4:08 am
by DrSlony
Ah, don't forget that AP2 has a new option in settings, "Always force the following EXIF value", just the workaround you need :]

PostPosted: Tue Jun 16, 2009 1:56 pm
by MJSfoto1956
Well, I'm not going to worry about it for now -- as long as I don't try to import JPG, everything seems to work just fine -- in fact better than importing the RAW files directly. So DxO and Autopano Pro turn out to be a good combination after all.

Michael

P.S. this looks like I will be purchasing APP as soon as I get my tax return check from IRS