I'm having trouble working with CZI files on Fiji/Image J on my Mac

Our Olympus FV1000 is under repair so we’ve done some imaging on a Zeiss confocal in our microscopy core. Images were saved as .CZI files and I’m having trouble opening them with the latest Fuji/ImageJ. The files open but the images are dim and not at all like what we saw on the Zeiss software. The mac is running OS 10.14.6. There are many options when opening these files, can someone point me to a how to site for more info. I did search! Thanks.