Author Topic: Another Hand Held Bracketing example  (Read 1866 times)

garry23

  • Hero Member
  • *****
  • Posts: 1547
Another Hand Held Bracketing example
« on: February 20, 2018, 11:04:52 PM »
An example of another image from my Winchester Cathedral trip last weekend. Once again showing the power of my new (auto) Hand Held Bracketing script.

In this capture the script decided to take the following bracket set with the Irix 11mm lens set at F/5.6:

    ISO 100 @ 1/250s
    ISO 800 @ 1/250s
    ISO 6400 @ 1/250s
    ISO 6400 @ 1/30s
    ISO 6400 @ 1/125s

After ingesting into Lightroom, doing a lens correction on each image, followed by an HDR Merge, I used Auto Tone in the Basic Panel to establish a starting point for a few more tweaks.

I then did a round trip to Photoshop, where I used one of my favorite filters to bring out some local contrast detail, namely NEXT from www.knowhowtransfer.com

I must say, as I was hand holding, I'm personally pleased with the image. What do you think for a hand held capture?




garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #1 on: March 03, 2018, 11:05:58 PM »
I'm still enjoying exploring the hand held brackets I took the other week, using my capture script: https://gist.github.com/pigeonhill/7efb6b13e34e366d2651ba574125a5fa

Here is a processed image from a bracket set where the script decided three was all it could 'squeeze in' at F/8 and 1/30: @ ISO 400, 1600 & 6400.




garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #2 on: March 11, 2018, 05:40:23 PM »
Mothering Sunday in the UK, so an excuse to pop back home to the Waltham Abbey area, where I grew up, and the Church. Wiki tells us that it has been a place of worship since the 7th century. The present building dates mainly from the early 12th century and is an example of Norman architecture. To the east of the existing church are traces of an enormous eastward enlargement of the building, begun following the re-foundation of the abbey in 1177.

In the Late Middle Ages, Waltham was one of the largest church buildings in England and a major site of pilgrimage; in 1540 was the last religious community to be closed during the Dissolution of the Monasteries. It is still an active parish church for the town.

The monastic buildings and those parts of the church east of the crossing were demolished at the dissolution, and the Norman crossing tower and transepts collapsed in 1553.

The present-day church consists of the nave of the Norman abbey church, the 14th-century lady chapel and west wall, and a 16th-century west tower, added after the dissolution.

King Harold Godwinson is said to be buried in the present churchyard.

One unusual feature is the nave ceiling made up of the signs of the zodiac. The signs of the zodiac marked the passage of time for medieval people and each symbol was given given a deeper Christian meaning by the church. The ceiling also shows the four elements of water, fire, air and earth.

These three images give a flavour of the church. All were taken using my hand held bracketing script and the pano is a 3 x exposure stack.

The script seems to be working well now. It brackets for the highlights and shadows, whilst respecting you are hand holding. If it can't do time bracketing from the highlights, then it takes ISO noise brackets. Thus you always have 6 images to play around with. The images below were processed in LR and a little bit of Photoshop to correct the Pano distortion.








garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #3 on: March 11, 2018, 11:42:20 PM »
...and another hand held example from my Waltham Abbey shoot :-)




IDA_ML

  • Senior
  • ****
  • Posts: 464
Re: Another Hand Held Bracketing example
« Reply #4 on: March 12, 2018, 04:43:09 PM »
@Garry23

I experimented a lot with your HHB method trying to figure out if it provides any advantages compared to the Dual ISO method.  My conclusion is that if there are any quality differences between both methods they really are very subtle.  The HHB method really provides very clean, almost noiseless  results but I struggled a lot trying to handhold all 3 (even 6) shots in such manner that non of them suffers from camera shake blur.  If even one of the brackets is blurry, you notice blurry areas in the final picture also.  The Dual ISO method seems to be more forgiving in that respect since you take only one shot and the final result depends entirely on that one shot.  If exposure time starts becoming critical for hand holding, I usually take 3-4 identical shots and chose the sharpest one, discarding the others.  With stabilized lenses I can go down to 1/4-th of a sec. and still have perfectly usable results.

The Dual ISO method also has its caveats, compared to the HHB method:

1) Theoretically, it provides reduced resolutions in the darkest and brightest areas of the shot.  In practice, it is extremely hard to see its effect visually even if pixel peeping at 100%.  I saw the difference only once, with a high-contrast interior shot, where the transparent curtains, partly covering  the windows, were made of a very fine meshed material.  At some locations, the horizontal threads of the mesh looked broken, obviously due to the Dual ISO effect at the resolution limit.  To notice this phenomenon however, one really needs to know where to look and what to look for.

2) It requires precise ETTR metering for the highlights, especially in high-contrast scenes.  If you overexpose them, the shot is gone.  If you underexpose the shot, trying to preserve the highlights, you may end up with some noise in the darkest areas due to reduced single-to-noise ratio there.  This again happened to me with a contrasty shot taken at Dual ISO 100/800.  When I changed the setting to 200/1600, the noise in the darkest areas disappeared almost completely and I had perfect detail and sharpness over the entire area of the picture.

Bottom line: 
-------------
My choice for handheld low-light photography is the Dual ISO method.  The risk for ending up with blurred shots as a result of camera shake is much lower, so is the post processing time.  In terms of image quality, dynamic range, colors and detail, the Dual ISO method provides excellent results but one needs to be precise with exposure to the right.  With tools like RAW-histogram and zebras, Magic Lantern makes this task easy.

garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #5 on: March 12, 2018, 06:53:07 PM »
@IDA_ML

Can’t really disagree with you.

I to would go Dual-ISO if the scene allowed it.

I wrote the script to augment Dual-ISO, ie when dual won’t hack it.

As for camera shake, that’s down to you and the FL.

I personally mainly use the script at very wide angles, ie my 11mm IRIX.  I also set the min shutter speed to 1/30, which works for me. I also always ETTR for the highlights.

I never get a blurred bracket  :)

Once again, thanks for the feedback. But as I said before, I wrote the script for my use, but publish as shareware  ;)

Cheers

Garry

IDA_ML

  • Senior
  • ****
  • Posts: 464
Re: Another Hand Held Bracketing example
« Reply #6 on: March 12, 2018, 09:54:43 PM »
Garry23,

I was wondering if you may be interested in performing the following comparative experiment.  Choose a beautiful cathedral scene with those marvelous color windows in the far background and take two identical tripod shots with your 11 mm lens - one with your HHB metod and one with Dual ISO.  Then, after processing them your way, post them here.  I would be curios to see the difference, especially in the high-contrast window areas where the differences will be most obvious.  I should appreciate if you do that.

garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #7 on: March 12, 2018, 10:04:00 PM »
@IDA_ML

I didn't write the script for tripod use: 'only' hand holding, ie shutter speeds faster than, say, 1/30s.

If I was on a Tripod I would bracket using the ML Auto Bracketing after I had set the exposure for the shadows.

In the hand holding case, I set the base exposure for the highlights and the script simply gives me the maximum exposure coverage.

Cheers

Garry

PS I've just combined the hand holding exposure and focus scripts into one unified script, ie Off, Exposure, Focus. Seems to work well, at least for me ;-) I'll likely post the new script in the next day or so.

IDA_ML

  • Senior
  • ****
  • Posts: 464
Re: Another Hand Held Bracketing example
« Reply #8 on: March 13, 2018, 09:39:02 AM »
Garry,

I know that!  I mentioned the tripod just because the two shots have to be absolutely identically composed to make a proper comparison.  This is difficult to do handheld.

garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #9 on: March 13, 2018, 05:46:09 PM »
@IDA_ML

Sounds like you have a plan.

As for me; I'm good to go with the script as is, with all its 'limitations'.

Cheers

Garry

garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #10 on: March 14, 2018, 10:04:32 AM »
As you may have picked up [;-)], I've been enjoying myself seeing how far I can go with hand held photography.

This example shows that we should not be fearful of hand holding in 'difficult' situations.

I was in a high DR environment, ie a church, and wanted to capture the grandeur of the vista, ie a pano.

This example is 24 hand held images: 4 x 6 exposure brackets, taken with an 11mm lens!

Of course, as I was not rotating around a 'nodal point' it is difficult to remove all distortion; but, over all, I'm pretty pleased with the result - at least as a record shot.





Postscript: for those that also like history, here are the details of the church: http://www.british-history.ac.uk/rchme/essex/vol2/pp237-246

IDA_ML

  • Senior
  • ****
  • Posts: 464
Re: Another Hand Held Bracketing example
« Reply #11 on: March 14, 2018, 10:51:17 AM »
@IDA_ML

Sounds like you have a plan.

Of course I have a plan - to save the world! :-))).  Am I asking too much?

By the way, your panorama is another example why I asked you to perform this test.  It looks quite overprocessed and with a strong pinkish magenta cast, nothing to do with your very first HHB photos.  From what I see, it does not seem to be very sharp either.  Take a look at that same scene with your eyes and check how the colors look like in reality.  Then compare it with your picture.  Is this really what you want to see?  In my opinion, if you make the same panorama using the Dual ISO method, you will enjoy a much more natural look, colors and better sharpness and detail too.  But I may be wrong.  This is the reason why I asked you for the above comparative test.

I have the feeling that you feel offended by my criticizm but I want to assure you that it is very good minded.  As I already told you, I greatly appreciate your great ideas and coding skills and I always wanted you to keep up with your excellent work.  But I also want that we all try to make things better and get the best out of Magic Lantern.  Hence the criticizm.  I applogize if I did not manage to express myself in the most polite way.  English is not my mother tongue.

garry23

  • Hero Member
  • *****
  • Posts: 1547
Re: Another Hand Held Bracketing example
« Reply #12 on: March 14, 2018, 06:09:26 PM »
@IDA_ML

I only posted the previous image to show the power of LR handling 24 hand held images, ie stitching them.

I didn't spend any time colour processing the image.

Now I know you are going to critique and mark me, I'll spend more time in Photoshop  ;) :) :) :) :)

Cheers

Garry