Bug report

Describe the bug
When loading a NEF file vips_magickload produces a image of the correct dimension while vips_magickload_buffer produces a image of dimension 160x120 (probably some embedded thumbnail). This small image is also produced when loading the image as a TIFF (which is what libvips identifies the image as).

To Reproduce
Steps to reproduce the behavior:

1. Use Image https://www.mannyphoto.com/D700D3/_DSC4175.NEF
2. Execute the following in python

import pyvips
img_bytes = open('./_DSC4175.NEF', 'rb').read()
img1 = pyvips.Image.magickload('./_DSC4175.NEF')
img2 = pyvips.Image.magickload_buffer(img_bytes)
print(img1.width, img2.width)

3. Output is 4284 160 not the expected 4284 4284.

Expected behavior
Both methods should produce the same image.

Actual behavior
Loading from buffer produces a much smaller image.

Environment

• OS: Arch Linux
• Vips: vips-8.14.1