New HDR Merge

[Littletank]

I would like to load a RAW image into the Develop Persona and create several versions of that image which I will then process in New HDR Merge. On the first look, a possible workflow seems to be quite convoluted because, amongst other things, to use a merge process requires the image to be either JPEG or TIFF. Could someone please suggest a workflow to produce three images from one RAW image which can then be blended in the Photo Persona.

[MEB]

Hi Littletank,

If i understood you correctly you want to generate a sub-exposed and and overexposed version of your RAW image so you can perform an HDR Merge as if you have taken a set of braketed shots. Is that correct? The HDR Merge function does support RAW images, but if you only have one to work with (rather than a set of 3, 5, whataver) you will not take much advantage of the higher dynamic range no matter how you edit the original image. If you want to simulate an HDR "look" with just one image you can use the Tone Mapping Persona to achieve it. If you still want to generate a set from the original RAW, load it in Develop Persona, adjust the exposure, shadow/highlight details etc as you see fit - you have to do this at least  twice: one for the overexposed version (to get details from the dark areas) which you them export as a TIFF and another for the subexposed (to get highlights detail) again exported as TIFF, then load all three (overexposed, subexposed and the corrct exposed version - also exported as TIFF) in the HDF Merge. No sure if i addressed you question correctly.

[Littletank]

Thank you MEB for taking the trouble to reply and, basically, you  are correct except that I am not necessarily looking for an HDR effect image. What I am trying to do is to re-cycle old colour transparencies which inevitably end up as B&W images. Until now my experience has been with ACR and PS and, after processing the scanned image in ACR the result could then be saved directly as a TIFF so I presume that in AP once the image has been developed it would then be exported as a TIFF. However, unlike with ACR, when I return to the Develop Persona the image I have is the one that has been developed and not the original image. My experience has led me to believe that there is often a lot of information in a colour slide if it can be extracted and this over and under exposed process seems to do this which is why I have used the original image for both over and under exposure. Would I be right, therefore, to achieve this in AP it would be necessary to load the original image each time I wanted to prepare a differently exposed image? 

 

Probably any of the merge processes might be suitable but the procedure to obtain the images would be the same.

[R C-R]

If you are talking about scanned transparencies (slides?) I do not understand how development factors into this unless somehow your scanner outputs RAW files.

 

In Affinity Photo, you can use the Develop Persona on any opened file -- it does not have to be a RAW file.

[Littletank]

E C-R, I use VueScan as the scanning software and it purports to give a RAW output. I don't think it's a true RAW but I use it. My trials so far have shown me that these files open directly in the Photo Persona and that all is well when transferred to the Develop Persona. More experimenting is called for and I am sure that the results will be what I am seeking, it is just a case of working out the best workflow.

[John Rostron]

I use VueScan and from what I read about its RAW format, these are tiff files (probably 16-bit). I very much doubt that you would be able to see any improvement by using the technique you describe. All the information you want is in that tiff file, so you may as well use that as your basis and use adjustments layers in the Photo persona to bring out shadows etc.

[Littletank]

Thank you for your comment, JR, you could be right, more experiments to try.

[R C-R]

From https://www.hamrick.com/vuescan/html/vuesc33.htm#outputrawfile (emphasis added):

Quote

Output | Raw file

 

(Professional Edition only)

This enables writing raw data from the scanner to a TIFF file.

The raw files are the result of the first of two steps VueScan performs: "scanning". The second step is "processing". These steps are described in the topic "How VueScan Works" in this User's Guide. By providing a mechanism to cleanly separate these two steps, VueScan provides great flexibility and offers options not available in most other scanner software.

You can perform the "processing" step later by setting Input | Source to "File". This lets you rescan images with different settings, without needing to rescan the media.

When the raw file is written depends on the setting of Output | Raw output with.

Raw files are always stored as TIFF files and can therefore be examined in image viewing and editing programs. Note, however that the resolution of raw files (as specified in Output | Raw file type) may be greater than some programs can read.

Little processing is done on raw files so they are a close representation of exactly what the scanner has produced. Raw files will not be filtered nor will color settings be applied. As a result, raw scans may look "wrong". 

Raw files contain as much data as the scanner was able to produce before any modifications may have been made, and are therefore good for archiving.

The image gamma value is 1.0 when there are two bytes (16-bits) per sample, and 2.2 when there is one byte (8-bits) per sample. Raw files saved with gamma 1.0 will look dark, but this is normal.

The one exception to this is if Output | Raw output with is set to "Save". In this case, the infrared cleaning and grain reduction is also done before saving the raw scan files.

Professional Option: This option is displayed when Prefs | Enable raw from disk is set or when not scanning from a file.

So basically, "Raw" is not the same as "RAW."

[Littletank]

Agreed!!

[KevW]

Hey just a quick question, when I try to process my RAW photos in HDR merge, they always process to a very unusable pink/purple tint. Where as I use the JPEG photos and they turn out perfect, yet I can’t touch up as well as I could with then RAW. 

Am I doing something wrong to cause this? 

 

Thank you,

Kevin.