My camera, a Nikon D7100, gives me the option to choose between two image areas”
- DX crop (24×16) uses the full 24mm x 16mm image area, uncropped.
- 1.3X (18x12mm) crops each image using an 18mm x 12mm image area.
Do I understand the math of these options?
I recommend David Busch’s Nikon D7100 Guide to Digital SLR Photography.Truthfully no, but I have a fantastic handbook on the D7100 by David Busch that says one argument for the 1.5X crop factor is that it “transforms any telephoto lens you have into a longer lens, which can be useful for sports, wildlife photography, and other endeavors that benefit from more reach.” of course, there’s more to it than that, and not everyone agrees, but, being a bird (and other wildlife) photographer, I decided it would be worth investigating.
This morning, instead of hitting the trail in search of photo opps, I walked out to our back patio, sat down on the bench and spent a half hour playing around with the settings. The greatest test of the added reach the 1.5X crop factor afforded me was these two hummingbirds. For some reason, the hummers have stopped coming to our sugar water feeders; however, they still fly through the back yard and love to rest (as hummingbirds do) on the tip-top branches of our neighbor’s apple tree where they have a good view of the feeders and any back yard action. That’s where this little one was sitting when I took his picture:
It’s certainly not a closeup or even a good picture, but as a capture of a tiny bird about 18 feet (or so) from my lens, it’s better than anything I got with out using the crop factor. In my half hour of bench time, I captured the following images using the added reach afforded by the crop factor:
hippie with food on his nose
house finch in the apple tree
A note about the chipmunk: Chipmunks cant’s fly, but they can climb!!As we all know, chipmunks can’t fly, but they can climb. This summer my husband transformed an old step ladder into a bird feeding station. The birds like it, as do the squirrels and chipmunks. This little chippy jumped onto the bottom step and dashed upward to reach the big blocks of seeds (designed for the woodpeckers). As you can see, he was enjoying his meal.
That’s it for my first experiment with the 1.5X crop factor. Did it give my camera more reach? Yes. Is it “magical?” Maybe not, but I did get closer pictures with it than I have without it, so I guess I will keep on using it. It does lower the resolution of my images from 24mm to about 15-16, but since I usually don’t print my picture, that’s not a great concern, just something to keep in mind when I might want to print them for a contest or a gift or something.
So there you have it. If you have any thoughts to share about this topic, please add them to the comment section.
Thanks for visiting.
Carolyn aka Skip