Stitching + Stacking + Bracketing

Any workflow and software tips for achieving

panorama stitching and
focus stacking and
exposure bracketing

all-in-one for the same image. I know it's a tall order.

Frame your first image
Shoot Bracketed Frames
Roll Focus
Shoot Bracketed Frames
Roll Focus
(Repeat As Needed)
Pan
Repeat Above Steps

In Post:
Blend HDR For Each Set Of Focus Points
Blend Focus Stacks
Stitch Pano from Completed Images

That's how I'd attack it...

FlyingPhotog wrote in post #14726083
Frame your first image
Shoot Bracketed Frames
Roll Focus
Shoot Bracketed Frames
Roll Focus
(Repeat As Needed)
Pan
Repeat Above Steps

In Post:
Blend HDR For Each Set Of Focus Points
Blend Focus Stacks
Stitch Pano from Completed Images

That's how I'd attack it...

That's pretty much how I do it.

after doing some reading i think the best workflow might be

1. use the Promote control to automate the camera shooting.
2. exposure bracketing comes first. several bracket shots per focus point
3. then change the focus point. dont move the camera yet
4. then repeat step 2 for each of your focus points
5. then move the camera for the first panorama shot
6. then repeat steps 2-4 for each separate panorama shot
7. blend in Helicon Focus first those frames with the same exposure but different focus points
8. blend in EnfuseGUI or PHotomatix For exposure correction.
9. blend in PTGUI for stitching last because stiching dark exposures is problematic.
10. remove ghosting with PTGUIs masking tool
11. export to Photoshop for retouching and sharpening and de-noising
12. whala

PhotoAcute will do HDR and focus stacking simultaneously. PSCS will do HDR merge and focus stacking (blending layers) although with less control than dedicated stacking apps.

The Promote Control does focus point control as well for select cameras - i.e., it can do the HDR and focus stack bracketing all in a single automated session.

http://www.hdrlabs.com …m/YaBB.pl?num=1​311206654/

Watch the second movie here:

https://support.promot​esystems.com …iewarticle&kbar​ticleid=17

but watch the first one as well for the basics of focus stacking.

If you have a motorized pano head, the pano head+promote will permit full automation of all three variables (pano+hdr+stack).

As far as the merge workflow, I would think merging each exposure bracket to HDR first is better, because if your focus stack is different at each exposure (the stacking app cannot segment the underexposed or overexposed scene well) then when you HDR merge the stacked images, you could potentially get artifacts where the exposures differ due to the stacking errors. If Helicon Focus permits you to store the masking for a stack as a template, so that each subsequent stack is stacked identically, this would alleviate the above potential problem.

Conversely, your stacking app has to support 32bit images if you want to merge to HDR and then stack the HDR images. Otherwise, you may have to merge to HDR, tone map - making sure each HDR image set gets tonemapped identically - and then stack the LDR tonemapped images and then stitch those.

The ideal situation would be to stay in 32bit land as long as possible. So:

1) Merge each exposure set to HDR for each focus position;
2) stack the HDR images into a single HDR image at that pano position;
3) stitch the HDR pano segments into a single HDR pano;
4) tonemap the final 32 bit pano into a LDR pano for final processing.

kirk

It appears as though the new Magic Lantern will also combine exposure and focus bracketing:

http://www.magiclanter​n.fm

"As far as the merge workflow, I would think merging each exposure bracket to HDR first is better",

Helicon Focus' website says:

"Helicon Focus supports JPEG, TIFF, BMP, PSD and various RAW formats with 8 and 16 bits per channel."

I don't know of any stacking software that supports 32 bit format.

Hi Texshooter,

Photoshop will probably do it - although you will have fewer options to control the stacking. I will try to generate an example today if I can get a spare moment.

To stack, you use Auto-Blend Layers in Stack mode. I have not verified if this will work in 32-bit mode, so stand by, or try it yourself!

Basically, take each Exposure Sequence and Merge to HDRPro - this will produce a single, 32-bit image. You will get a single 32-bit image for each focus position in the focus stack.

Next, put each of these 32-bit images in successive layers in a single document - select all of the layers and use the Auto-Blend command in Stack mode. This will produce a single 32-bit stacked image that will represent one segment of your panorama. Then you will stitch these 32-bit stacked segments into a single panoramic composite.

See if that works.

If your panorama is not a full spherical pano, you may be able to take the resulting stacked HDR segments and Photomerge them in PS to your final 32-bit pano composite. That is, you may be able to use Photoshop for all of your workflow steps. You can even tone the image from 32-bit to 16-bit and then do all of the final processing on the 16-bit image all without leaving Photoshop. Add to that the fact that, if you shot raw, you can convert all of your images in Photoshop using ACR and you start to realize why Photoshop is a pretty powerful tool.

I saw your post on The Luminous Landscape

http://www.luminous-landscape.com/forum/in​dex.php?topic=69242.0

and noticed that someone responded by asking you:

In other words, the forum member (Milt) wants to know why you need to stay in 32-bit after you do your merge to HDR. He is not aware that you are going to stitch to panorama - you want to preserve as much tonal range as possible and avoid tonal changes across the pano stitch. Staying in 32-bit until the final tonemapping of the panorama is thus the "best" route - although you may be able to avoid having to do this if the scene permits (i.e., the sun is not preset, or there are no huge tonal changes across portions of the pano). Try shooting a non-focus-stacked HDR panorama and try tonemapping each HDR segment prior to stitching and you will see how uneven the tonal range can get across the panorama. This is typically because the tonemapping may take into account the tonal range on a per-segment basis as the compression is applied - segments with a large tonal range will get mapped differently than segments with a smaller tonal range. If large areas of uniform tone, like the sky, are present, the transition in these areas from one segment to the next will be obvious and incongruous. Also - this will be a time-consuming process in terms of data collection. If the lighting in which you are going to shoot is not controlled (i.e., daylight) you are going to have to deal with changing sun position, clouds moving in front of the sun, etc. Just be aware that the HDR side of things may get funky if the lighting changes dramatically during an HDR+Focus Stack image acquisition session. I'm just saying - it is hard enough when shooting an HDR panorama, let alone when you are taking an HDR bracket for several focus positions of a single pano segment.

Which brings me to the question I should have asked previously - what are you shooting that requires HDR + focus stacking + Panoramic Stitching? Or is this an exercise just to investigate the multi-dimensional compositing workflow - just to see if it can be done.

Next, add a fourth dimension ... time lapse! Hello Promote Control.

Kirk

"Photoshop will probably do it - although you will have fewer options to control the stacking."

That was my hunch. That's why I am shopping for more specialized software to do everything- focus stacking, HDR, and stitching. I haven't actually practiced with this multi-dimensional technque yet. Just kicking tires right now by reading up on it. I have Photomatix is all, but to tell you the truth I'm not liking the tone mapped look. I heard someone say it looks like "clown vomit." I tend to agree, but I'm here to explore my options.

"To stack, you use Auto-Blend Layers in Stack mode. I have not verified if this will work in 32-bit mode"

If I understood this article correctly
http://www.photoshopca​fe.com …ls/HDR_ps/hdr-ps.htmthink
I think Photoshop can view and edit 32-bit images but can't save them as 32-bit files. VIEW>32 BIT VIEWING OPTION

" Staying in 32-bit until the final tonemapping of the panorama is thus the "best" route"

My suspisions exactly, although I've never tried tonemapping first before panorama stitching, or before focus stacking for that matter. I wonder if there are before/after images of all these workflow options somewhere on the web. I think that would be valuable info for us all to compare. Hopefully a fellow geek with too much time to spare will write up a white paper on this one.

"Which brings me to the question I should have asked previously - what are you shooting that requires HDR + focus stacking + Panoramic Stitching? Or is this an exercise just to investigate the multi-dimensional compositing workflow - just to see if it can be done."

Just to see if it can be done. I'm window shopping and beefing up on the technical aspects for now.

Next, add a fourth dimension ... time lapse! Hello Promote Control.

I'll choke to death. Baby steps first. Speaking of Promote, here's a good starter tutorial I watched on doing HDR panos.

http://www.youtube.com …wog&index=10&fe​ature=plcp

I'm left with questions, especially with how to remove ghosting during the workflow, but it's a good starting point for peeps like me who don't know much about HDR+Focus+Pano. The instructor uses EnfuseGui for the HDR effect and PTGUI for the stitching. The video got me wondering how HeliconFocus could fit in.

Photoshop will save 32 bit images in several formats, primarily PSD, EXR and HDR. The "problem" with viewing HDR data on a LDR display is that some of the luminance data will fall outside of the display's range - that is, if you want to see the stuff in the shadows of an HDR dataset, the highlight areas will not be visible - they will be blown out. It does not mean they are not there, it is just that the range of the data in your HDR image is greater than the range the display can show you all at once. Same for highlights - you want to see all that detail in the clouds, the shadows in the scene will plug. You can use the 32 bit Exposure Slider in the bottom left of the application window to adjust the viewing range of the 32 bit image so you can inspect different tonal ranges of the image. The 32 bit viewing options are simply some more control over how Photoshop displays the HDR on an LDR device.

See:

http://www.hdrlabs.com​/tutorials/index.html

for some valuable information on HDR panoramic workflow, examples, etc. The approach is varied and depends upon the tools at your disposal. For example, PTGui will permit full 32bit workflow if you are doing HDR panoramas. Let's say you have shot a panorama with 5 segments, each with a 7 exposure HDR sequence. You can feed PTGui the 35 images and it will merge each exposure set and then stitch them all in one go. You can output a 32 bit panorama (as well as tonemapped LDR composite if you want) for tonemapping in your favorite HDR app or in PS. Alternatively, you could use Photomatix to merge your pano segments into HDRs and then feed PTGui the HDR segments for stitching. Some prefer the automated workflow Photomatix offers in this regard. Further, I know folks who will do the automated batch HDR merge in Photomatix and, in addition to spitting out HDR images for each pano segment, they will also output a small JPEG tonemapped LDR version - this is what they feed to PTGui to make the stitch, as the smaller file size makes the stitching process more interactive. Once they get a good stitch in terms of image alignment, they make a template of the stitch - this captures all of the distortion correction and alignment data. Then they load the full-res, 32-bit images into PTGui and apply the template and let PTGui crunch away. This way the heavy lifting was done on the small JPEGs, permitting a faster workflow.

You are definitely engaging in baptism by fire if you are learning all of this simultaneously for the first time. Aim High!

The main difference between working in full 32-bit land versus Enfuse is that an HDR image (data) preserves (is recording) the scene luminance. Enfuse simply blends the "best" exposed pixels in a series of images into a single image - it does not care about the scene-referred luminance information necessary. So, your instructor may be telling you that his or her work using Enfuse (EnfuseGUI) is "HDR" but it is not ever treading into HDR dataland. Tonal range compression (blending)? Yes. HDR data? No.

We'll get this figured out. Still working today - will try later on to cobble together an example.

kirk

Here is a thumbnail of the exposure range.2 EV steps.

kirk

"I've been meaning to purchase Helicon Focus so I did and used it."

I'm curious if anybody reading this thread has worked with both Helicon and Zerrene, and which one they prefer.

"I ended up Batch Processing each exposure bracket in Photomatix, applying a preset that gave a not horrible tone map."

I have to say your final image does not have that fake tone mapped look. Did you tone map or did you use the exposure fusion process option within Photomatix? I've tried in the past the exposure fusion option but still get clown vomit but not nearly as bad as the full-force HDR tone mapping.

"I tried to do everything in PS and it failed miserably".

I'm not surprised. Maybe Version CS12 will be up to snuff.

"I'll keep working on a better workflow."

To compare, I would try processing the exposure fusion (EF) and pan stitching all in PTGUI, without Photomatix, to see if the results are better or worse.

Can't wait for the day one plugin will do it all. No more hopscotching between programs.

Here is another treatment of the same data - this time I focus-stacked each exposure (-4, -2, 0, +2, +4) into a single stacked image at that particular exposure - I used small 16 bit TIFFS for each image. Then I fed the stacked exposures for pano segments 1 and 2 (5 exposures at 2 pano segments = 10 images) into PTGui and it automatically detected that they were image sequences and prompted me to use HDR linking. So I did and it stitched the set into a 32bit pano. Done.

That approach seems more reasonable because you end up with a 32bit pano that you can tonemap to your heart;s content. I was impressed at Helicon Focus' ability to stack the very under and over exposed images properly.

Again, not going for beauty here, so the tone mapping is not real nice. Close enough.

This is the workflow I would use.

kirk

Here is the same file, toned in ACR 7.1. Remember - you can save 32bit HDR files as 32bit TIFFs and open them in ACR/LR and use the exposure, highlights, shadows, etc. to tone the 32 bit file to LDR! Much more natural look, which is why it is best to end your whole process with a HDR file and then tone it any way you want to LDR, instead of committing to LDR early in the workflow and then deciding you don't like the look ...