Digital Blending with 5400 II ?

  • Thread starter Thread starter fiatuni
  • Start date Start date
fiatuni said:
Hello,

Does someone already used the technique of digital blending to work
around the dMax problem ?

http://www.luminous-landscape.com/tutorials/digital-blending.shtml
Click to expand...

Don does, even though he's doing that with a scanner and not with a
digital camera.

You can also see the list of software to do sub-pixel alignment that I
recently posted; I guess you should mostly look at HDR Shop and Optipix,
which seem to be written with multiple exposures in mind, though other
programs may work as well.

by LjL
(e-mail address removed)
 
Hello,

Does someone already used the technique of digital blending to work
around the dMax problem ?

http://www.luminous-landscape.com/tutorials/digital-blending.shtml
Click to expand...

As Lorenzo mentioned many people do that and have developed a number
of different strategies.

If you check this newsgroup's archives there have been several
messages on the topic. Search for a "Twin Scan" message for example.
Even though things have moved on from there, it's a start. Another
term often used for this procedure is "contrast masking".

The two key aspects are to align the images afterwards and to "tone
map" i.e. "color coordinate" the two scans before merging them so
there is no visible border.

Don.
 
fiatuni said:
Hello,

Does someone already used the technique of digital blending to work
around the dMax problem ?

http://www.luminous-landscape.com/tutorials/digital-blending.shtml
Click to expand...

Sure, double scanning or similar should work just as well as that
digital camera technique. You simply need to be able to control scanner
exposure, then you do one scan for highlights, and another for shadow
detail. The tough part is combining those two scans smoothly. That
article does point out a nice approach, and might be somewhere to start.

Ciao!

Gordon Moat
A G Studio
<http://www.allgstudio.com>
 
Don said:
As Lorenzo mentioned many people do that and have developed a number
of different strategies.

If you check this newsgroup's archives there have been several
messages on the topic. Search for a "Twin Scan" message for example.
Even though things have moved on from there, it's a start. Another
term often used for this procedure is "contrast masking".

The two key aspects are to align the images afterwards and to "tone
map" i.e. "color coordinate" the two scans before merging them so
there is no visible border.
Click to expand...

The referred link failed to address the challenges of aligning the two
images you described.
 
The referred link failed to address the challenges of aligning the two
images you described.
Click to expand...

Yes, I came across that too. Unfortunately, not a lot of importance is
given to image alignment on various pages dealing with contrast
masking, digital blending, etc.

I think it's because all those methods usually involve a lot of
"fudging" when it comes to combining the two images. They are usually
merged using a lot of "feathering" and colors are not mapped at all.

That's also why most of those pages don't even address the difficult
case of gradients i.e., when the border between the two images falls
in a middle of a gradient.

Don.
 
Don said:
Yes, I came across that too. Unfortunately, not a lot of importance is
given to image alignment on various pages dealing with contrast
masking, digital blending, etc.

I think it's because all those methods usually involve a lot of
"fudging" when it comes to combining the two images. They are usually
merged using a lot of "feathering" and colors are not mapped at all.

That's also why most of those pages don't even address the difficult
case of gradients i.e., when the border between the two images falls
in a middle of a gradient.
Click to expand...

Most PS books and tutorials are guilty when it comes to describing more
challenging editing situations. They would hand pick images just right
for their descriptions, talk only about the easy steps, and omit the
really difficult part.
 
You won't have alignment problems if you do Vuescan scan-from-disk from
a single raw file. Of course, this approach is kind of hobbled, since
you're only using one physical scan. More often though, I'll just use
Photoshop's higlight shadow tool

I also do similar, with digital camera raw files: outputting 2 tiffs,
say one normal, and a second with reduced brightness, to recover
highlights. Here's some examples:

http://www.photo.net/photodb/folder?folder_id=525039

(not sure how this link will work, perhaps it only works for me cus I'm
logged in there? Anyway, it's in my blended exposure portfolio at
Photo.net)

Or Photoshop's higlight shadow tool?

Oh, I found one thing that improved the look of the Lum. Land. blended
exposure workflow: reduce the transparency to 50%, of the added layer.
Read here:

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00DRcb
 
Mendel said:
You won't have alignment problems if you do Vuescan scan-from-disk from
a single raw file.
Click to expand...

Are you suggesting that Vuescan can scan an image twice and have them
perfectly aligned? This is NOT the science fiction group.
 
Are you suggesting that Vuescan can scan an image twice and have them
perfectly aligned? This is NOT the science fiction group.
Click to expand...

It seems Mendel is suggesting that you put two copies of the same scan
as layers on top of each other and adjust them separately before merging
them. I don't think that's what they call 'digital blending' though.
You may as well apply different tonal adjustments to highlight areas and
shadow areas on one layer, for instance based on 'select color range'.
 
You won't have alignment problems if you do Vuescan scan-from-disk from
a single raw file. Of course, this approach is kind of hobbled, since
you're only using one physical scan.
Click to expand...

Duh? ;o)

You won't have alignment problems with *any* software if you only use
*one* scan!

I don't think even Vuescan can mess that up... Actually it can! ;o)

Don.
 
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