Why You’d Resize Photos on the D7100
The Nikon D7100 shoots at 24.1 megapixels, which produces images around 6000 x 4000 pixels. That’s great for printing, cropping, and getting maximum detail, but it’s way more than you need for most everyday uses. An email attachment doesn’t need to be 15 MB. An Instagram post looks the same at 2 megapixels as it does at 24. And if you’re uploading dozens of photos to a cloud album, smaller files transfer faster and take up less storage.
The D7100 gives you two approaches to resizing: doing it right on the camera using the built-in Retouch Menu, or transferring the files to a computer and resizing with software like Nikon ViewNX-i or NX Studio. Both work, and each has its advantages.
In-Camera Resize Using the Retouch Menu
The D7100’s Retouch Menu has a Resize option that creates a smaller copy of any JPEG image stored on your memory card. The original stays untouched. Here’s how to use it:
1. Press the MENU button.
2. Navigate to the Retouch Menu (the paintbrush icon).
3. Scroll down to Resize and press OK.
4. Choose the size you want from the list.
5. Select the image (or images) you want to resize.
6. Press OK to create the resized copy.
The camera saves the new smaller file alongside the original. Both files stay on the card, so you never lose the full-resolution version.
Available Size Options
The Resize function offers several preset sizes:
1.25 megapixels (1280 x 856): Good for web use and email attachments. Files are small and load quickly.
2.5 megapixels (1920 x 1280): Works well for social media posts and basic online sharing. This is close to full HD resolution.
5 megapixels (2720 x 1808): A solid middle ground. Big enough for a decent print at 5×7 inches, small enough to email without clogging someone’s inbox.
10 megapixels (3856 x 2568): Good for when you want to reduce file size but keep enough resolution for larger prints up to about 11×14 inches.
The exact pixel dimensions may vary slightly depending on the aspect ratio and crop settings. All resized copies are saved as JPEG files.
Resizing for Email and Social Media
For email, the 1.25 MP or 2.5 MP options are usually enough. Most email providers have a 25 MB attachment limit, and at 2.5 MP you can attach several photos in one message without hitting that cap.
For social media, 2.5 MP is the sweet spot. Instagram maxes out at 1080 pixels wide for feed posts, and Facebook compresses everything above about 2048 pixels anyway. Sending a 24 MP file to these platforms just means the platform does the resizing for you, often with worse compression. A pre-resized image can actually look better because you control the quality.
Batch Resizing In-Camera
The D7100’s Resize function lets you select multiple images at once. After choosing a resize option, you can scroll through your photos and mark several images for resizing in one batch. Press OK when you’ve selected everything, and the camera creates resized copies of all the marked photos.
This is handy when you’ve just finished a shoot and want to create a set of smaller files for quick sharing without touching a computer. It’s slower than doing it on a PC, but it works when you’re on the go.
Image Quality Settings: L/M/S and Fine/Normal/Basic
If you know you’ll need smaller files before you even start shooting, you can set the D7100’s image quality and size to produce smaller JPEGs from the start.
Press the QUAL button on the top of the camera body while rotating the rear command dial to choose between:
Size: Large (L), Medium (M), or Small (S). Large is the full 24.1 MP. Medium drops to about 13.5 MP. Small goes down to about 6 MP.
Quality: Fine, Normal, or Basic. Fine uses less compression and keeps more detail. Basic compresses more and produces smaller files. Normal is a good middle ground.
Shooting at Medium/Fine gives you smaller files than Large/Fine, with enough resolution for most uses. If you’re shooting casual photos and know you’ll never print larger than 8×10, Medium is a reasonable choice that saves card space and makes transfers faster.
That said, it’s generally better to shoot at Large/Fine and resize later. You can always make a big file smaller, but you can’t add pixels back to a small file.
NEF (RAW) vs. JPEG: Why It Matters for Resizing
The D7100 can shoot in NEF (Nikon’s RAW format), JPEG, or both at the same time. This choice has a big impact on how you handle resizing.
JPEG files are processed in-camera. The camera applies white balance, sharpening, contrast, and noise reduction, then compresses the image. When you resize a JPEG (whether on the camera or on a computer), you’re working with an already-processed, already-compressed file. Every time you re-save a JPEG, you lose a tiny bit of quality.
NEF (RAW) files contain all the data from the sensor with no processing or compression. They’re bigger (about 25 to 35 MB each on the D7100 compared to 5 to 15 MB for a Fine JPEG), but they give you total control. You can adjust exposure, white balance, and colors in editing software before you export, and then export at whatever size and quality you want.
The in-camera Resize function only works with JPEGs. If you shoot RAW only, you’ll need to transfer the files to a computer for resizing. But the payoff is worth it. Starting from a RAW file and exporting a resized JPEG gives you the best quality at any size.
Resizing on a Computer with Nikon Software
Nikon ViewNX-i and NX Studio
Nikon’s free software lets you browse, edit, and export photos from the D7100. NX Studio (released as a replacement for ViewNX-i) handles both NEF and JPEG files.
To resize in NX Studio:
1. Open the image in NX Studio.
2. Go to File > Export (or use the Export button in the toolbar).
3. In the Export dialog, set the output format to JPEG.
4. Under Image Size, choose a specific pixel dimension or a percentage of the original.
5. Set the JPEG quality slider. Around 80 to 90% gives an excellent balance of quality and file size.
6. Choose a destination folder and click Export.
NX Studio handles the conversion from RAW to JPEG and the resizing in one step. This gives you a clean, properly processed image at exactly the size you need.
Other Software Options
Adobe Lightroom, Capture One, and free tools like GIMP or IrfanView can also resize D7100 images. Lightroom’s Export dialog is especially convenient because you can create export presets (for example, “Email size, 1200px wide, 80% quality”) and apply them to batches of hundreds of photos with one click.
For quick one-off resizing on Windows, right-click a JPEG, select Edit with Photos, and use the Resize option. On Mac, Preview can resize images through Tools > Adjust Size.
Why Shooting RAW Gives You More Options Later
Here’s the practical argument for shooting RAW on the D7100, even if it takes more storage and a bit more work:
Imagine you took a photo at a family event. In JPEG mode, the camera made decisions about white balance, exposure, and color. If the white balance is slightly off (yellowish indoor lighting, for example), fixing it in a JPEG degrades the image. Fixing it in a RAW file is clean and lossless because you’re working with the original sensor data.
When it comes time to resize that photo, you can export from the same RAW file at different sizes: a full-resolution version for a framed print, a medium version for a photo book, and a small version for a text message. Each export is generated fresh from the original data, so every version looks its best.
If you shot JPEG only, you’re resizing an already-processed file each time. It still works, and for casual shooting the quality difference is small. But for photos you care about, especially anything you might print or want to edit later, RAW gives you room to work that JPEG doesn’t.
The D7100 has dual SD card slots. A good workflow is to shoot RAW to one card and JPEG to the other. You always have a quick-share JPEG ready, plus the full RAW file if you need it later.
