- last edited on by
Danny
When converting multiple (for me, up to ~250) CR3 files to TIFF, an option is provided to resize files and default values are provided that are not the same as the input images, last used value and not always the same. I am seeking to understand why these defaults are selected by the software and is it better for me to accept them or make some change (back to the original size, for example). I see the possibility that this relates to in camera lens corrections or IBIS and have not experimented with non-Canon lenses that do not have correction data (which is my next step). I am producing a series of TIFF files to be focus stacked in Zerene Stacker which requires all images to be exactly (to the pixel!) the same size but will stack and edit successfully series that the DPP4 routine refuses or gives errors on some images. This comes up most often when pushing the matter a bit beyond 'normal'. Can anyone explain to me what is happening here and offer suggestions that might help (other than not try to shoot this sort of thing)?
If distortion correction is enabled in the camera menu, then DPP will default to what the camera has done and possibly produce a different size image, but I see this mostly with wide angle lenses. Saving a recipe from DPP with distortion correction disabled and applying it to all of the CR3 files before converting to TIFF might prevent this.
I have never stacked 250 images. I have used hugin on my Linux computer for stacking when the alignment is not close enough for DPP. Hugin requires manually selecting points near the corners of each image and matching those points with the same object in the other images which is tedious. This image was stacked using DPP, but the lighting was not ideal.
I have not done stacks of small things. Stacks of flowers are difficult if there is any wind. DPP automatically disables some of the camera settings when stacking raw files. If planning to stack TIFF files exported by DPP, then I suggest applying the same recipe to all of the files before export.
DLO might enable diffraction correction, but I do not think that is a problem. It is distortion correction that seems to me to change the number of pixels in the image and the correction might vary with focus distance. I also disable peripheral illumination correction if I am planning to stack and only apply it to the composite image later if desired. I think it is best to also not do unsharp mask until after stacking.
In some cases, disabling noise reduction might be a good thing.
| Depth Composite Focus Stack | 8 images |
| Artist | John Moyer |
| F Number | 9.0 |
| ISO | 100 |
| Shutter Speed Value | 1/64 |
| Focal Length | 18.0 mm |
| Camera Temperature | 32 C |
| Lens ID | Canon EF-S 18-135mm f/3.5-5.6 IS USM |
| Field Of View | 63.8 deg |
| Hyperfocal Distance | 1.93 m |
Stacking images of the very small presents a different set of challenges than simple cloe-ups. This Coleus flower shows weakness in the lower part of the stalk of the stamen making it look 'see through'. This was 180 TIFF's assembled in Zerene Stacker. I need to see what the effect would be with fewer input images at a greater spacing (higher number in Focus Bracketing). I am unaware of a resource that helps select best aperture, spacing and use of other options when producing or assembling stacks. DPP4 takes a long time to make this many TIFF's so if the result would be as good with fewer, it would be great.
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