irpano wrote:

A question  if it hasn't been asked allready.
When attempting to shoot a panorama and capture the full dynamic range within the pano (Say 10 stops for example and not all tiles within the pano having the same dynamic range), I have been using Aperture mode on my Canon 30D and on ocassions the braket function (+3 -3) is insufficient to capture the full dynamic range in the pano , resulting, generally in blown highlights.
I have a copy of DSLR Remote pro, an application that lets you specify up to 15 stops of exposure compensation and was wondering if -
A)   should I capture each tile so that the exposure Historgram is within the limits (Shadows not filled in and highlights not blown) - this may take 5 bracketed images, then move to the next tile and repeat bracket - this time with only 3 exposures.
B) will APP cope with the different number of images in a tile or does it require the same amount of images per tile.

c) What is the best way to seperate each tile in the pano so that each can be run through Photomatix pro

Hope someone can help
John

Hi John! 

I very rarely experienced a situation where -2/0/+2 wasn´t sufficient. It depends where you set the center. If you have very strong highlights in the scene you should set the "center"-time at -1.
Btw.: NEVER use aperture mode for bracketing - use manual time steps. Using the aperture mode means VERY different DOF between exposures when you use -2/0/+2. That might cause hard to stitch pictures.

When your "center" is at f:11 you´ll get 5,6/11/22 . . . imagine the DOF-differences . .
I myself process brackets FIRST in Photomatix and give mapped TIFFs to APP.
I tested DSLR Remote Pro using up to 9 steps of bracketing. That´s fine in extreme situations. And only then. On the other hand the 9 brackets at 1 step-value can lead to maybe more finegraded colors.

best, Klaus

Correction: i misunderstood that "aperture-mode" thing! Thought it´s something different.
sorry! (thanks Maciek and Andrew for reminding me )

Last edited by klausesser (2009-03-20 18:48:28)

The way you are bracketing is fine, aperture remains constant while exposure time changes. APP can handle that, but this is assuming that you do your tonemapping and exposure blending within APP, and this is a problem since APP doesn't yet have good tonemapping tools. The "HDR color correction" mode will probably give you a great result though, I just never had any luck with getting a nice image using RH4. "HDR color correction" without RH4 often does wonders.

I used to use Photomatix-2.5 or something like that a long time ago, and it wouldn't properly blend panorama layers where some had empty holes (alpha) - these are what you would get if you put your manually and differently bracketed images into APP and rendered to layers. You would get several layers and they would look like swiss cheese. Now I have Photomatix-3.1 but I don't use it much because it crashes a lot under wine (linux), so I don't know whether 3.1 would be able to properly make a HDR from such swiss cheese layers and then to tonemap that HDR, but AFAIK Photomatix-2.something couldn't do it. Enfuse, on the other hand, will handle it just fine.

Bracketing by 1EV if you use JPG from a DSLR is a bit overkill. If you shoot RAW, then bracketing by 1EV is definitely overkill. I wouldn't do it unless I got paid to do it. Compact and bridge cameras have a much shallower dynamic range than DSLR, so 1EV on compact/bridge could make a noticable difference, but you probably wont see a difference between these two tonenapped sets if you used a DSLR:

-4EV -3EV -2EV -1EV 0EV +1EV +2EV +3EV +4EV
-4EV      -2EV      0EV      +2EV      +4EV

If you use Enfuse for exposure blending, then keep in mind that Enfuse doesn't need all those brackets - all it needs is a photo with well exposed shadows, well exposed highlights, and well exposed mid tones. Often this means just two photos.
Example: pano inside a room, sunshine outside the window. 0EV inside, -6EV outside. With Enfuse you just need those two images. With HDR you probably need 0EV, -2EV, -4EV, -6EV for a nice result.

If you test any of these things, please share your results, I always enjoy testing and seeing how things actually work out :]

DrSlony wrote:

ps. you might want to glance at these threads. I haven't checked them in a while, and perhaps I should write a new post since a lot of time has passed and I learned new things, but since I relied on tests I hope that most of these are true :]
Why its better to tonemap (*fuse) AFTER stitching
hdr workflow test

You can use Phtx without geting this "effect"-look. The  way Phtx work in my eyes is the best of all (i tried all). Getting this "effect" look definitely can´t be blamed to Phtx . .
I use Phtx all the time when i shoot bracketed. If i don´t want to get an "effect" look i don´t have it.
That way i used it from it´s first version on.

I realized - after using SpheronHDR cameras with more than 20 bracket-steps or 1DsMkIII and 5D and 20D using DRLR Remote Pro with 12 steps - that on a 20D which i mainly use for stitching a setting of -2/0/+2 when shooting RAW is the most universal setting. Measuring extreme highlights or deepest shadows first and centering the settings related to these you can get 90% of the needed range.

As 2nd step i process the RAWs in Phtx and map/compress them carefully (!).
Sometimes i use a RAW converter first and give 16bit TIFFs to Phtx when i mean the RAW convertion is better done then.

Tests with the actual 14bit RAW are very pleasing (16bit RAW from digibacks of course are even more pleasing . . ).
I would NOT use RAWs directly in ANY stitcher, sorry. If you don´t want the additional steps in your workflow - don´t use bracketing . .

Rendering three or more bracketed layers in APP and make them HDR/tonemapping in Phtx i had ghostings in 50% of the cases. Even when i said Phtx to avoid just that.

So my finding is to use fusing or Phtx FIRST on RAWs or TIFFs or even JPGs to combine bracketed shots and only THEN stitch them.

best, Klaus

here a JPG bracketing: (extreme bright light outside, shadowy inside. Mallorca in August 08)

Last edited by klausesser (2009-03-21 12:47:25)

"Do you have any way of preventing that when using batch, even if some source photo stacks cover only very bright things with no dark things in the frame? Or do you manually redo the failed ones later?"

I always select a set of 3 pictures from the whole set which i see are critical and a set of which seem to be avarage. These i process alone and find an appropriate setting for both. Then i save the settings without saving the resulted image.
These settings i feed the batch with. Voilá.

(i´m referring to Photomatix!).

here´s another one with really extreme lights and darks: (i kept the expression of "brightness" in the outside-light. Could have done it darker - but that wouldn´s show the light-proportions. It WAS extremely bright outside - leveling that too much changs the feel of it.)

Last edited by klausesser (2009-03-21 16:03:51)

"Though this covers the situation where Enfuse is used before stitching better than the situation where it's used after stitching, "

Yes - i always suggest to use Phtx or others FIRST and only THEN stitch.

best, Klaus

(the link to enfuse doesn´t work)

Last edited by klausesser (2009-03-21 16:06:17)

GURL wrote:

klausesser wrote:

(the link to enfuse doesn´t work)

Though the previous one worked for me, you could try this one: http://panorama.dyndns.org/EandE-documentation/

Doesn´t work on Safari and Firefox . . . (maybe they don´t like Apple?)

best, Klaus

DrSlony wrote:

Both work on firefox3/linux

Our provider had a temporary crash i guess - took some hours and now it works again.

Now i can open the link.

best, Klaus

DrSlony wrote:

klausesser do you have any test case panoramas where several of the stacks have nothing in them except for the sky (and the sun)? Like in the example below, the FOV is so small that some source images just have bright sky in them. I would like to see how your photomatix method will handle this case, if you have the time :]

yep!

here there are (some):
1st.:  about   80 shots
2nd.: about 120 shots
3rd.: about   60 shots
there were lots of shots showing just sky - as in your example.

Last edited by klausesser (2009-03-22 15:41:04)

Hi irpano!

With moving clouds it´s better to shoot in landscape-modus - one shot captures a wider horizontal area.
I use portrait-mode most of the time.
Sometimes it helps trying different detection-strenghts. With "big skies" i often use "low".

best, Klaus