How to cut image into equal parts:
I use sample image 1400px x 426px
You want 7 parts
1. Use line tool to make vertical line top to botttom of image and rasterize the shape layer
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2. Copy Shape layer 7 more times (CTRL+J) to have 8 Shapes. (from Shape 1 to Shape 1 copy 7)
3. Select "Shape 1" layer together with "Background" layer and align to LEFT
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4. Select "Shape 1 copy 7" layer together with "Background" layer and align to RIGHT
5. Select ALL Shape layers and DISTRIBUTE HORIZONTAL CENTRES. This will move all lines to 7 equal spacing across image.
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6. Delete "Shape 1" and "Shape 1 copy 7", so you have 6 lines.
6. Select ALL 6 lines and make GROUP (CTRL+G) to make easy for ON and OFF selection later.
Next use CROP Tool
1. Use CROP tool UNCONSTRAINED. Uncheck DELETE CROPPED PIXELS. In Crop settings gear icon - check "Use Classic Mode" and uncheck "Enable Crop Shield"
2. Drag RIGHT handle close to first line and note new width (mine was 209px)
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3. Click on Unconstrained box and click "Size & Resolution R"
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4. Type in size of new width (mine was 209px) and new height (mine was 426px) and click OK
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5. Name New Crop Preset. (mine is Panorama Cut)
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6. Now press ENTER to do crop. You only see now first image
7. Turn OFF Group 1 and do save as "image-1.JPG" - you can name what you like
8. Next do "CTRL+ALT+Z" to undo. you now see full image again.
9. Turn ON Group 1 to see lines again
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10. Move crop area with arrow key (Shift+arrow for faster) to next part of image so you see lines both sides. Press ENTER to crop. You now see next part of image
Repeat moves from number 7 to get all images you need
I hope this what you wanted.