feeling loupey
There are many instances where it has been difficult to assess results when taking shots in the field. This has been especially true when taking waterfall or ICM images - both instances where the result is tied directly to the depiction of motion within the image.
The primary issue for me has been the limited size of the camera LCD screen, but even when the image is magnified viewing finer detail can be extremely difficult due to glare and reflected light on the screen.
One tool I have found really that helps remedy that issue is to use a Hoodman loupe. This type of loupe sits on top of the LCD screen and basically acts as a sunshade, blocking out extraneous light and presenting a more clearer image to the eye. An added bonus for my ageing eyes is that the Hoodman offers a + 3 diopter adjustment to accommodate those with less than perfect vision.
I would highly recommend this accessory, even with its relatively expensive $90 price tag (you may be able to find cheaper alternatives) . Being able to focus on image quality at location can save disappointment when you arrive home or perhaps the requirement of a return trip to location.