I don´t know if this is the right place.
I have a personal project, which involves the printing of several nature pictures on poster via an online vendor.
The pictures are taken mostly in NEF format, some are in TIFF format. Around 25 mb for the original file.
The posters can be printed in sizes like 60x90cm with a maximum resolution of 300 dpi. A limitation is that they can be uploaded with a maxium filesize of 100MB.
At the moment I am post editing and at the end converting into TIFF on Affinity, then I go through Gigapixel AI and rescale in the poster size (which means always an increase) , resolution 300 DPI.
The outcome if stored in TIFF is always a huge file, which can´t be uploaded to the printing site. Sometimes DNG is small enough, some others I have saved the result in JPG maximum quality.
Am I doing anything wrong? My goal is to loose as few quality as possible.
Many thanks for any hint.