In the Ripon Cathedral example, look on the Masks tab and DSC01617.jpg, 
photo #3. You can see the green include masks so that when it is toggled to 
be included in the final pano, it will mask out the other images in those 
bright areas.

Then go to the "Panorama preview" and you can see what happens when you 
toggle on and off photo #3. If it is toggled on (i.e. all photos actives), 
then you can decrease the brightness until the window is not blown out, 
this is around EV5.97 but the rest of the pano is a bit dark. Export this 
to get an "underexposed" pano. Deactivate photo #3 and return the 
brightness of the pano to "normal" (should be EV4.97) and export this 
version for a default exposure. There's no need to for brighter version for 
this particular pano but the same would apply if there were some shadow 
areas you wanted to brighten up a bit. Now run enfuse on the exported dark 
and normal exposures to get an exposure blended version of the pano.

This one 
https://www.360cities.net/image/france-toulouse-notre-dame-du-taur-south-chapel 
required a range of exposure times from 20s to 1/15th and I exposure 
blended both under and overexposed exports.

A thing to note is that this technique of rendering outputs at different 
brightnesses doesn't require taking extra shots in some cases. It may be 
that the brightness in one frame/direction is much different from the 
brightness in another, although the intra-frame contrast may be tolerable 
in each shot.

On Monday, 3 January 2022 at 20:28:39 UTC chaosjug wrote:

> I think the shadows have the same pattern than the original images. So 
> vignetting might be an issue, but then I would expect to see the same 
> issue 
> with the bracket version. It is also sometimes much less and hardly 
> noticeable 
> but I'm not sure what I did. It might be, that the photometric 
> optimisation 
> isn't always working as it should. That part is pretty much black magic 
> for me 
> at the moment. The geometric I've mostly figured out. Only camera 
> translations 
> for the nadir shot is giving me troubles but I get mostly acceptable 
> results 
> without it.
>
> So you are doing one pano in nomal EV. And then one for under or over 
> exposure 
> where you might add another frame which was shot explicitly for that like 
> in 
> the Ripon Cathedral Library? I wasn't expecting to find the EV correction 
> on 
> what I had stamped as beginners interface. I may need to look more closely 
> what I can change the as well.
>
> Am Montag, 3. Januar 2022, 19:14:59 CET schrieb 'dkloi' via hugin and 
> other 
> free panoramic software:
> > You're losing out on a lot of potential of your camera not shooting raw. 
> In
> > high contrast situations, this is especially the case where the ability 
> to
> > recover highlights and boost shadows as needed in post-processing is very
> > advantageous, not to mention the ability to tweak white balance easily,
> > even in extreme lighting conditions. The limited bit depth together with
> > lossy compression of jpg images does pose significant limitations when
> > doing panoramic photography in challenging situations.
> > 
> > Not sure what you mean by, " With auto, the white walls get shadows."
> > Perhaps this is due to vignetting, lens light fall-off?
> > 
> > In order to tame intra-scene contrast, the trick I use is to produce 2 
> (or
> > more) output versions of the same scene at different brightnesses. This 
> is
> > using the "Panorama preview" window and the "EV:" setting. You can 
> output a
> > default brightness (hit the green arrow) and output a pano, then produce
> > other output panos that are over and under exposed to capture the shadow
> > and highlight detail as required. Then use enfuse to exposure blend the 3
> > panos together,
> > see
> > 
> https://i1.wp.com/www.dkloi.co.uk/wp-content/uploads/2020/01/06EnfuseExampl
> > e.png from http://www.dkloi.co.uk/?p=1454
> > 
> > MFT fisheye lenses aren't that expensive, the Samyang 7.5mm is about £220
> > from Amazon. I'm not sure whether this requires 4, 5, or 6 shots around,
> > but even a 6+Z+N pattern would save you a lot of time.
> > 
> > Glad you found my articles useful. They're not really aimed at the 
> novice,
> > the already existing step-by-step guides are probably better for those 
> who
> > are starting off. But this group is always a good place to ask questions
> > about things that aren't clear.
> > 
> > On Tuesday, 28 December 2021 at 21:37:23 UTC chaosjug wrote:
> > > I'll give raw a try, but I haven't used it much before and struggle to 
> get
> > > better results than just using the jpeg...
> > > 
> > > I have tried to capture the same room once on auto and once with 
> bracket
> > > (+/-1EV) to get a feeling for the difference. With auto, the white 
> walls
> > > get
> > > shadows. With bracket that is no issue. But in both cases the final 
> image
> > > looks
> > > as if taken at the same exposure all around. So dark parts are too dark
> > > and
> > > bright parts too bright. Even if I add a specially exposed shot e.g. 
> of a
> > > bright window and set the masks accordingly.
> > > Looking at your Ripon Cathedral Library example, the trick seems to be 
> to
> > > make
> > > two panos and use enblend again to merge them. But how do I actually
> > > create a
> > > darker pano? And for the final enblend I probably need to pass the 
> masks
> > > again,
> > > right?
> > > 
> > > I guess I'll have to invest into a fisheye lens if I don't want to send
> > > hours
> > > on setting control points ... I'm just a bit hesitant as I have a OMD
> > > E-M10
> > > Mark II and the MFT format seems to be dying out. Which is sad, as I
> > > really
> > > like the form factor. Much less to carry on hikes which is my main use
> > > case.
> > > 
> > > Your articles are great, because they are not a step by step guide 
> without
> > > explanation as so many tutorials on the basic how to stitch with hugin.
> > > But on
> > > the other side I would need some more step by step because I can't
> > > translate
> > > that into how to do this for real like above.
> > > And of course: looking at how others are doing things is a great way to
> > > learn
> > > imho.
> > > 
> > > Am Montag, 20. Dezember 2021, 17:41:53 CET schrieb 'dkloi' via hugin 
> and
> > > other
> > > 
> > > free panoramic software:
> > > > You should definitely be shooting raw. Apart from the ability to 
> adjust
> > > > white balance, the amount of exposure latitude in the raw file is
> > > 
> > > typically
> > > 
> > > > much greater than what is preserved in an in-camera jpg, especially 
> if
> > > 
> > > you
> > > 
> > > > are using a larger sensor camera e.g. DSLR or mirrorless.
> > > > 
> > > > In raw development, I often max out highlight recovery and use
> > > 
> > > extensively
> > > 
> > > > shadow recovery. This can gain a lot of detail that would normally be
> > > 
> > > lost
> > > 
> > > > in standard development.
> > > > 
> > > > If I bracket, it's usually in steps of 2EV. I usually don't bother 
> with
> > > > overexposing but mainly care about making sure I don't lose highlight
> > > > detail, hence may shoot -2EV or -3EV in addition to the autoexposure
> > > 
> > > value.
> > > 
> > > > But this all depends on your camera and its sensor characteristics, 
> you
> > > 
> > > may
> > > 
> > > > need the +EV brackets if shadow performance isn't good.
> > > > 
> > > > Lens calibration isn't usually required but could help in some
> > > > situations
> > > > where there are not enough control points to give a good lens 
> geometry
> > > > optimisation. I haven't bothered calibrating my lens, other than
> > > 
> > > inputting
> > > 
> > > > the calibrated focal length (as the lens does not transmit metadata 
> to
> > > 
> > > the
> > > 
> > > > camera).
> > > > 
> > > > To make your life easier, I suggest getting a fisheye lens, there are
> > > 
> > > quite
> > > 
> > > > a few affordable options. This would reduce the number of shots you 
> need
> > > 
> > > to
> > > 
> > > > take as well as reduce the processing time. What output size do you 
> need
> > > > and what camera are you using?
> > > > 
> > > > What isn't covered in the articles I mentioned that you'd like to 
> know
> > > 
> > > more
> > > 
> > > > about? Have you played around with the example files?
> > > > 
> > > > On Sunday, 19 December 2021 at 23:59:26 UTC chaosjug wrote:
> > > > > Hi,
> > > > > 
> > > > > thanks a lot for your input!
> > > > > My bracket setting was 0.3EV so no wonder I was missing output 
> layers.
> > > 
> > > I
> > > 
> > > > > had
> > > > > to search a bit, because the german translation is a bit fuzzy. In
> > > 
> > > german
> > > 
> > > > > it
> > > > > is named "Belichtungsebenen" which I would translate as exposure
> > > 
> > > layer, so
> > > 
> > > > > it
> > > > > is not so clear that this is for the output layers.
> > > > > From what I read in the articles you linked, I'm shooting way too 
> many
> > > > > pictures. I'll give it a try with less.
> > > > > At the moment I shoot jpgs but I could do raw. Is there much 
> benefit?
> > > > > I
> > > > > see
> > > > > different white balance in the original images but hugin seems to
> > > 
> > > handle
> > > 
> > > > > that
> > > > > just fine.
> > > > > 
> > > > > I also tried multiblend. It seems to have a bit more trouble if the
> > > > > controlpoints are not perfect but it is indeed faster. That doesn't
> > > 
> > > help
> > > 
> > > > > with
> > > > > nona and enfuse which took a lot of time with my big stacks but if 
> I
> > > 
> > > don't
> > > 
> > > > > need that, then it will speed up the process a lot.
> > > > > 
> > > > > I also found some articles about lens calibration. How do I know 
> if I
> > > > > should
> > > > > do that?
> > > > > 
> > > > > If anyone knows articles/tutorials about 360° and/or indoor panos
> > > 
> > > please
> > > 
> > > > > share. I find it really hard to find something that covers more 
> than
> > > 
> > > the
> > > 
> > > > > basics
> > > > > and is not outdated (or at least old and thus unclear to me if 
> still
> > > > > valid).
> > > > > 
> > > > > Am Sonntag, 19. Dezember 2021, 21:53:41 CET schrieb 'dkloi' via 
> hugin
> > > 
> > > and
> > > 
> > > > > other free panoramic software:
> > > > > > From the Hugin manual at
> > > 
> > > https://wiki.panotools.org/Hugin_Stitcher_tab
> > > 
> > > > > > "If *Exposure fused from any arrangement* is enabled then hugin 
> will
> > > > > > seam
> > > > > > blend images with similar exposure with enblend
> > > > > > <https://wiki.panotools.org/Enblend> and than it will exposure 
> fuse
> > > > > > <
> > > 
> > > 
> https://wiki.panotools.org/index.php?title=Exposure_fusion&action=edit&red
> > > 
> > > > > l
> > > > > 
> > > > > > ink=1> them using enfuse <https://wiki.panotools.org/Enfuse>. 
> This
> > > > > 
> > > > > variant
> > > > > 
> > > > > > is often much more successful than *Exposure fused from stacks* 
> in
> > > 
> > > two
> > > 
> > > > > > situations:
> > > > > > 
> > > > > > - Where entire panoramas have been shot at each EV level
> > > 
> > > consecutively
> > > 
> > > > > > rather than each shot bracketed <
> > > 
> > > https://wiki.panotools.org/Bracketing>,
> > > 
> > > > > > in this case it isn't guaranteed that shots will line up into the
> > > > > > approximate stacks expected by the *Exposure fused from stacks*
> > > 
> > > option.
> > > 
> > > > > > - When the panorama has been shot entirely on automatic 
> exposure, in
> > > > > > this situation it is useful to seam blend adjacent photos with 
> small
> > > 
> > > EV
> > > 
> > > > > > differences, but then exposure fuse larger EV differences - As
> > > > > > effectively happens with this option.
> > > > > > 
> > > > > > Note that Hugin uses a default threshold of 0.5 EV exposure
> > > 
> > > difference
> > > 
> > > > > > to
> > > > > > determine which photos can be fused into each layer. This 
> threshold
> > > 
> > > can
> > > 
> > > > > be
> > > > > 
> > > > > > modified on the Photos tab <
> > > 
> > > https://wiki.panotools.org/Hugin_Photos_tab>
> > > 
> > > > > in
> > > > > 
> > > > > > the Expert mode (selecting group by Output layers)."
> > > > > > 
> > > > > > What exposure bracket settings are you using? If it's 0.5EV 
> steps,
> > > 
> > > then
> > > 
> > > > > > maybe Hugin is combining 2 exposure planes?
> > > > > > 
> > > > > > Are you able to share your project and a set of images for
> > > > > > diagnosis?
> > > > > > Downsized, compressed would be fine for testing exposure fusion.
> > > > > > 
> > > > > > There are other ways of handling high contrast panos. I have some
> > > > > 
> > > > > articles
> > > > > 
> > > > > > that may be useful
> > > > > > at http://www.dkloi.co.uk/?p=1454 http://www.dkloi.co.uk/?p=1501
> > > > > > and http://www.dkloi.co.uk/?p=1518
> > > > > > 
> > > > > > On Saturday, 18 December 2021 at 08:15:03 UTC chaosjug wrote:
> > > > > > > Hi,
> > > > > > > 
> > > > > > > I'm looking for the best way to do make 360° indoor panoramas. 
> I'm
> > > > > 
> > > > > using a
> > > > > 
> > > > > > > panorama head and the images align well. No issues there.
> > > > > > > What I'm wondering is this:
> > > > > > > I'm shooting stack with different exposure. Is that the right
> > > 
> > > thing? I
> > > 
> > > > > > > need
> > > > > > > different exposure when shooting against a window versus a dark
> > > 
> > > part
> > > 
> > > > > > > of
> > > > > > > the
> > > > > > > room.
> > > > > > > How should I build the final image from that? I tried the 
> "fused"
> > > 
> > > and
> > > 
> > > > > > > "blended_fused" but it is not totally clear to me what is 
> actually
> > > 
> > > the
> > > 
> > > > > > > difference. Is it the order if stacking or building the 
> panorama
> > > > > > > is
> > > > > 
> > > > > done
> > > > > 
> > > > > > > first?
> > > > > > > Or is there anything else to it? Which is better?
> > > > > > > 
> > > > > > > When using "blended_fused" I get three intermediate panoramas 
> with
> > > > > > > different
> > > > > > > exposure although there are 7 images in each stack. It is 
> unclear
> > > 
> > > to
> > > 
> > > > > > > me
> > > > > > > why
> > > > > > > that happens. I get the following warnings:
> > > > > > > enblend: warning: some images are redundant and will not be
> > > > > > > blended
> > > > > > > enblend: note: usually this means that at least one of the 
> images
> > > > > > > enblend: note: does not belong to the set
> > > > > > > 
> > > > > > > As I don't have a wide angle lens, I need a lot of images and 
> thus
> > > 
> > > it
> > > 
> > > > > > > takes a
> > > > > > > lot of time to merge. Are there any tricks to speed things up?
> > > > > > > 
> > > > > > > Regards,
> > > > > > > Stephan
>
>
>
>
>

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