Converting Grayscale GeoTIFF to PNG using QGIS results in all black image

Question

I have a GeoTIFF in QGIS that I created by merging some images inside QGIS.
I use Raster>Conversion>Translate. And save it as a PNG.
I then open the image in both, Photoshop and Windows Photo Viewer and it looks entirely black.
Anyway to solve this?
I would like to use the image to print/use it in a document.
Edit: Here is the gdal info:
Driver
GDAL provider
GTiff
GeoTIFF
Dataset Description
AREA_OR_POINT=Area
Band 1
STATISTICS_MAXIMUM=1079
STATISTICS_MEAN=252.34346333641
STATISTICS_MINIMUM=1
STATISTICS_STDDEV=118.63833194341
Dimensions
X: 5400 Y: 3600 Bands: 1
Origin
-63,-37.6667
Pixel Size
0.000277778,-0.000277778
No Data Value
0 
Data Type
UInt16 - Sixteen bit unsigned integer 
Pyramid overviews
Layer Spatial Reference System
+proj=longlat +datum=WGS84 +no_defs
Layer Extent (layer original source projection)
-63.0000010703059985,-38.6666649293319793 : -61.5000010691059984,-37.6666649285319792
Band
Band 1
Band No
1
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user2856 · Accepted Answer

Your raster is 16bit single band.  You need to rescale to a rendered 3 band 8bit dataset.

Add your raster to QGIS and use the layer properties -> symbology to get it looking like you want:

Right click raster layer and select export -> save as...in the context menu.  Change output mode to rendered image and tick Create VRT:

Then use the Translate (convert format) tool to output a PNG, make sure you change output datatype to Byte:

Output png displayed in image editing software:

A. Mort · Answer

You can also use QGIS (or straight GDAL) to convert your GeoTIFF to a grayscale single band 8bit PNG so it will display efficiently in Photoshop and Windows Photo Viewer with no visual quality loss and a smaller file size.

In QGIS: Raster -> Conversion -> Translate

Note the command if you want to script this to do in GDAL:

gdal_translate -ot Byte -of PNG -scale D:/16bit.tif D:/8bit.png

Converting Grayscale GeoTIFF to PNG using QGIS results in all black image

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