PTGui 13.9 trial: separating two identically-exposed bracketed sets into 10 blend planes (worked in 11.32)

[Martin Strouhal]

Dear PTGui Support,

I am a licensed user of PTGui 11.32 and I am currently testing the trial version of PTGui 13.9. I am very interested in purchasing the upgrade to version 13, but I am facing a critical workflow issue in the trial regarding the export of blend planes that I need to resolve before upgrading.

In my project, I shot the sky twice (Set A and Set B) with identical exposure parameters (same shutter speed, aperture, and ISO). I need to export both sets into a single PSB file as separated Blend Planes (10 planes in total: 5 for Set A, 5 for Set B) so I can manually mask the clouds in Photoshop.

My old workflow in PTGui 11.32:
To output 10 separate blend planes instead of merging the two sky sets into 5, I manually changed the ISO value of the second sky set in the "Image Parameters" tab. PTGui 11 would then output 10 separated blend planes into one PSB file, completely preserving the original brightness and pixel data of the source TIFF files.

The observed behavior in the PTGui 13.9 trial:
By default, PTGui 13 outputs only 5 blend planes, merging Set A and Set B together into the same layers.
When I attempt to separate them using my old method of changing the ISO in "Image Parameters", the output is severely degraded: the darkest exposure becomes extremely noisy, and the brighter exposures are blown out to pure white. On top of that, PTGui still outputs only 5 blend planes instead of the expected 10.

I also tried the officially recommended approach of varying exposure time instead of ISO (as suggested in the PTGui HDR tutorial). This avoided the noise/clipping problem, since the brightness of the source pixels was untouched, but the result was otherwise the same: PTGui still merged Set A and Set B into 5 blend planes instead of 10.

I have tried switching the HDR Workflow to "Blend first, then merge to HDR" and disabling "Exposure Compensation", but neither changing the ISO values nor the exposure time values succeeds in separating the two sets into distinct planes without side effects.

My question:
How can I output two bracketed sets shot with identical exposure settings as separated blend planes (10 planes in total) into a single PSB file in v13, without PTGui altering the original brightness or exposure of the source TIFF files?

Thank you for your time and advice.

Best regards,

Martin Strouhal, QEP

[PTGui Support]

Hi Martin,

There might be other ways to do this, but I don't see why your approach
would not work in PTGui 13. If you change the ISO of those images, PTGui
would see them as a separate EV and not link them with the other images.

Are you making a significant change to the ISO value, or do you change
100 into 100.00001 ?

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion visit https://groups.google.com/d/msgid/
> ptgui/18287371-a444-411f-a46b-a0089b724e64n%40googlegroups.com <https://
> groups.google.com/d/msgid/ptgui/18287371-a444-411f-a46b-
> a0089b724e64n%40googlegroups.com?utm_medium=email&utm_source=footer>.

[Martin Strouhal]

Hi Joost,

Thanks for the quick reply!

To answer your question directly: yes, it's a significant change, not a negligible one like 100 → 100.00001. I actually tested both extremes to isolate the variable:

- A huge ISO difference between the two sets
- A small but still clearly significant ISO difference between the two sets

In both cases the result is the same: PTGui still only outputs 5 blend planes, never 10. I'm attaching two screenshots of the resulting PSB opened in Photoshop (iso-change-huge.png and iso-change-small.png) so you can see exactly what I mean.

In both screenshots the Layers panel shows the identical structure:
- Blend plane (EV+4)
- Blend plane (EV+2)
- Blend plane (EV0)
- Blend plane (EV-2)
- Blend plane (EV-4)
- Blended panorama

So regardless of whether the ISO change is huge or small, PTGui always produces exactly these same 5 planes — never a separate set of 5 for the second series.

The only difference between the two screenshots is the quality of the content, not the number of planes. In iso-change-huge.png, the "Blend plane (EV+4)" layer is visibly degraded — washed out, low contrast, almost a veiling-glare/fog look, with detail lost in the snow and sky. In iso-change-small.png, the same "Blend plane (EV+4)" layer looks completely normal — sharp, correct contra the horizon.

So it seems the magnitude of the ISO change only affects how much the pixel brightness gets physically altered (i.e. how badly that plane gets degraded) — it doesn't affect whether PTGui splits the two series into separate planes at all. Even with a very large ISO difference, PTGui still treats both series as belonging to the same 5 exposure levels rather than creating 10.

Is there something else (besides ISO) that PTGui 13 uses to decide same bracket pattern should be split into separate blend planes? Or
is there a way to force this split without it affecting the actual source images?

I'm also attaching the project file (13a_DSC4990 Panorama.pts) in case it's helpful. Note it references ~400 external TIFF source files that aren't included (too
large to attach), so it won't fully open/render without them — but king / EV values should still be visible if you'd like to take a look.

Thanks again for your help!

Best regards,
Martin

[Martin Strouhal]

Screenshots

Dne neděle 16. srpna 2026 v 13:48:37 UTC+2 uživatel Martin Strouhal napsal:

[PTGui Support]

I'm sorry, it's not going to work. The only way to get 10 blend planes
in PTGui 13 is by grouping and linking the images in sets of 10. But
this would break HDR processing.

I thought PTGui 11 worked the same (and what you describe might have
worked in v10) but if you say it worked in 11.32 then must be
misremembering this.

The way to do this in v13 is to split your work in two projects (a
separate one for the extra sky image). You could probably use a template
to facilitate this.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion visit https://groups.google.com/d/msgid/ptgui/

> e465bf1b-740c-4687-ad81-50d53b3072ben%40googlegroups.com <https://
> groups.google.com/d/msgid/ptgui/e465bf1b-740c-4687-
> ad81-50d53b3072ben%40googlegroups.com?utm_medium=email&utm_source=footer>.

[Erik Krause]

Am 16.08.2026 um 13:12 schrieb Martin Strouhal:

> How can I output two bracketed sets shot with identical exposure settings
> as separated blend planes (10 planes in total) into a single PSB file

Could you make downsized jpeg copies of your source images available for
download? I'd like to see how far I can get with them. Use wetransfer,
dropbox or similar.

--
Erik Krause
http://www.erik-krause.de

[Martin Strouhal]

Hi Erik,

Thank you very much for offering to take a look — I really appreciate it.

I've packaged and uploaded downsized JPEG copies of the source images, along with a ready-to-use PTGui project file referencing them (same exposure bracket structure and setup as actual project). It's aligned and masked, so it should be ready for you to open and experiment with directly.

https://storage.to/01tExeZZI

Please let me know if you need anything else from my side, or if a different subset of images would be more useful — happy to help however I can.

Thanks again for taking the time to look into this, it means a lot.

Best regards,
Martin

Dne neděle 16. srpna 2026 v 20:42:30 UTC+2 uživatel Erik Krause napsal:

[Erik Krause]

Am 16.08.2026 um 21:57 schrieb Martin Strouhal:

> Please let me know if you need anything else from my side, or if a
> different subset of images would be more useful — happy to help however I
> can.

I assume you want the images starting with group 49 (DSC5250) to be on a
separate layer.

[Martin Strouhal]

Yes, exactly right, thank you!

Dne neděle 16. srpna 2026 v 22:12:06 UTC+2 uživatel Erik Krause napsal:

[Erik Krause]

Am 16.08.2026 um 21:57 schrieb Martin Strouhal:

> I've packaged and uploaded downsized JPEG copies of the source images,
> along with a ready-to-use PTGui project file referencing them (same
> exposure bracket structure and setup as actual project). It's aligned and
> masked, so it should be ready for you to open and experiment with directly.

I can confirm that it works the way you intended in PTGui 11, at least
after I increased the ISO difference. With 500 and 800 I got only 7
blend planes :-)

I can confirm that it doesn't work the same way in PTGui 13, and I found
no way to work around this other than creating two separate output
files. Also, technically, I think it is not correct to merge different
exposures into the same blend plane, at least as long as "Exposure
compensation" is off. Joost?

I remember having recognized this problem earlier, but then didn't
bother, since I always merge bracketed images before stitching using
SNS-HDR lite (in batch).

However, did you consider masking the clouds in PTGui? I'll suppose the
results would be better anyway, since it has zero overlap blender. See
the nearby vultures in
https://worldwidepanorama.org/go/n9991?v=73.948l21.593l17.731

[PTGui Support]

Earlier versions of PTGui assigned blend planes simply based on exposure
(where exposure is calculated from the combination of exposure time,
aperture and ISO).

So if you had 10 different exposures, you would get 10 blend planes.
Each blend plane contains images with exactly that exposure.

The problem is that this doesn't work for bracketed images in auto
exposure mode. HDR panoramas had to be taken in M mode for consistent
exposure times. When someone took bracketed images in Av mode, many
blend planes were created containing only a partial panorama.

At some point this was changed (apparently between v11 and v12): now
PTGui creates blend planes based on the index of images in their linked
group. So every first image will go into blend plane 1, every second
into blend plane 2. This way PTGui can handle bracketed images taken in
Av mode, solving this long standing complaint. Unfortunately this breaks
your workflow.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

[Erik Krause]

Am 17.08.26 um 09:59 schrieb 'PTGui Support' via PTGui Support:

> At some point this was changed (apparently between v11 and v12): now
> PTGui creates blend planes based on the index of images in their linked
> group. So every first image will go into blend plane 1, every second
> into blend plane 2. This way PTGui can handle bracketed images taken in
> Av mode, solving this long standing complaint.

Please make this optional, perhaps depending on the "Exposure
compensation" setting and whether blend planes are selected. I'd never
expect to have different exposures in a single blend plane. This somehow
defeats the idea of blend planes altogether.

[Martin Strouhal]

Hi Joost, hi Erik,

Joost, thanks for the explanation — that clears up why it always collapsed to exactly 5 planes no matter what I changed.

Erik, thank you for testing this yourself and comparing v11 vs v13!

I'd like to add my voice to Erik's request: it would be good if the old exposure-based assignment could be made available again, at least as an option (maybe tied to "Exposure compensation" or the blend planes setting, as Erik suggested). I'd also expect a blend plane to only contain images of the same exposure.

For now I'll go with splitting the work into two separate projects, as suggested.

Best regards,
Martin

Dne pondělí 17. srpna 2026 v 12:46:57 UTC+2 uživatel Erik Krause napsal:

[PTGui Support]

@Erik: it might not be ideal but I'd say it's better to have blend
planes containing mixed exposures than to have multiple incomplete blend
planes, breaking the HDR functionality and breaking users' expectations.

This change solved a real issue: If you go back a few years in the forum
posts you'll see many users surprised that they cannot use HDR or
exposure fusion for their Av bracketed images. They would be told they
shot wrong and should have used M mode.

Just bracket in M mode to avoid this. Also, PTGui will default to the
'HDR first, then blend' workflow when possible.

Making this configurable is of course possible (and I've added it to the
wish list) but I'm hesitant to do this. It's a significant change, it
would add another incomprehensible (to most users) checkbox and would
AFAIK only help for this specific use case.

@Martin: another solution might be this:

Load all images in one project, don't adjust ISO. Align everything
together. Then in the Create Panorama tab, use the 'Include Images' list
to output to output two panoramas, each with a subset of the images. You
can batch toggle the checkboxes by selecting multiple and pressing the
space bar.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

> http://www.erik-krause.de <http://www.erik-krause.de>

>
> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion visit https://groups.google.com/d/msgid/

> ptgui/34481518-c4e3-4d49-a04e-53238919d3f8n%40googlegroups.com <https://
> groups.google.com/d/msgid/ptgui/34481518-c4e3-4d49-
> a04e-53238919d3f8n%40googlegroups.com?utm_medium=email&utm_source=footer>.

[Erik Krause]

Am 17.08.26 um 14:34 schrieb 'PTGui Support' via PTGui Support:

> This change solved a real issue: If you go back a few years in the forum
> posts you'll see many users surprised that they cannot use HDR or
> exposure fusion for their Av bracketed images. They would be told they
> shot wrong and should have used M mode.

Yes, I know that very well, and I can understand that the change was
necessary — especially, though not solely, to accommodate beginners. I’m
very much in favor of this change, and I’ve also argued in favor of
“Merge First, Then Stitch.”

However, I think it’s questionable whether it makes sense to adapt good
software to bad habits. Shooting exposure bracketing in Av mode
potentially yields worse results — certainly not better ones.

When I work in Av mode without HDR, I still have to enable “Exposure
Compensation” to get reasonably usable results. Why should it be any
different with HDR?

Furthermore, anyone who uses Blend Planes wants to employ an advanced
technique — they’re no longer a beginner — and wants to do things like
HDR merging in an external program. But that’s difficult if different
exposures have already been incorporated. That seems to run counter to
the concept of Blend Planes.