I've just started taking a few test shots with a new D700. I'm shooting in JPEGfine mode and according to the Memory Card Capacity Chart in the manual the images should be 5.7MB in size. But the images I'm getting range only from 2.7 to 3.3MB. I'm using a AF Nikkor 24-85 4D zoom (i.e. NOT a DX lens) and have tried both JPEG Compression options but am not getting the file size I'm expecting. Any thoughts?
#1. "RE: jpeg file size with D700" | In response to Reply # 0dankeny Nikonian since 29th May 2006Wed 24-Dec-08 01:51 PM
Welcome to Nikonians. Jpeg file size varies because of compression. The number of shots is an estimate and the D700 modifies the number as it goes based on a best guess algorithm developed by (and this part I have on the best authority--I made it up) French monks from the 11th Century. It's like how they sell airline tickets to more people than they have seats for, but never overbook. Look at your file sizes on disk.
For best results, shoot raw, shake don't stir, add an olive and enjoy. Merry Christmas or what have you.
#2. "RE: jpeg file size with D700" | In response to Reply # 1Wed 24-Dec-08 02:15 PM
Thanks for your response and your welcome!
I think my fundamental understanding of the file size/image quality relationship may be somewhat lacking. My initial question was because I assumed that since my jpegs taken at the "fine" setting were smaller than what the chart I mentioned lead me to expect (3MBish rather than 5.7ish) that they were of lower quality" than what might be possible, i.e. more MB=higher quality. But I have jpegs taken with my little Cannon G3 that are over 6MB and SURELY they are not of better quality than what the D700 is putting out at the fine jpeg setting?! Do I assume that the superior intelligence of my D700 means that at the fine jpeg setting it is always producing the best jpegs possible regardless of the actual file size?
And yes, I plan to start shooting RAW which will make all this somewhat beside the point (and which, based all all the debate about issues like Aperture vs NX is a whole new can of worms) but it seems like a basic issue that I'd like to get sorted out in my little brain.
#4. "RE: jpeg file size with D700" | In response to Reply # 2briantilley Nikonian since 26th Jan 2003Wed 24-Dec-08 02:51 PM | edited Wed 24-Dec-08 02:53 PM by briantilley
Again, welcome to Nikonians, Tom!
As David says, the figure in the manual is an "average" for a typical JPEG file. The actual size in practice varies quite a bit, particularly if you have selected Optimal Quality for your JPEG compression setting (D700 manual p.67). The more fine detail there is in the frame, the larger the file.
Using Optimal Quality, Large for Image size (p.69) and JPEG Fine for Image quality (p.64), my D700 produces files varying in size from under 3MB to over 10MB.
#5. "RE: jpeg file size with D700" | In response to Reply # 4Wed 24-Dec-08 03:11 PM
Ok, I think it's starting to sink in! The size of the jpeg file is not just a product of how you shoot it but also WHAT you shoot, i.e. as Brian says, more fine detail in the frame results in a larger file. Which confirms my sense that using settings of Optimal Quality,Large and JPEG Fine assures that I'll be getting the best possible quality and I shouldn't be so concerned about the resulting file size as an indicator of quality (even when my little old compact generates a larger one!).
Thanks for all the prompt input and clearing up a "Digital Photography 101" issue, what a great site!
PS maybe it's not such a "DP101" issue. I just talked to an experienced professional photographer who was far from clear on the file size/image quality issue
#7. "RE: jpeg file size with D700" | In response to Reply # 5Tongariro Registered since 14th Jul 2007Sat 27-Dec-08 10:57 AM
If you want the very best professional quality, you might want to consider shooting RAW. This preserves all of the image data, which you can process to suit your own tastes in camera with your settings and afterwards on a computer. If you use Capture NX2, then the settings you chose in camera (eg with regard to white balance, saturation, sharpening etc) will accompany the RAW file. If you like them, keep them. If you want to change them, you can do so. Saving NEF files doesn't degrade the quality, and you can revisit the changes later.
Incidentally, NEF files also vary in size, depending upon the detail of the image, and are much larger than JPG files.
#8. "RE: jpeg file size with D700" | In response to Reply # 7Sat 27-Dec-08 12:29 PM
As I mentioned in entry #2, I already plan to shoot in RAW but here's another issue: I would like to be shooting in RAW + jpeg and as a result of another entry in this forum I've been told that AP will ignore the JPEG version when importing an image recorded in both formats and only import the RAW file. Is this true? It seems like a pretty basic capability to be missing from APs functions.
#3. "RE: jpeg file size with D700" | In response to Reply # 0
If you look at the specs:
4,256 x 2,832 L
3,184 x 2,120 M
2,128 x 1,416 S
2,784 x 1,848 L
2,080 x 1,384 M
1,392 x 920 S
I don't think any of those work out to 5.7 MB. If you have the camera in DX mode with a non-DX lens the uncompressed size would be about 5 MB, but with compression it would be closer to the 3 MB that your seeing. Which is smaller than say shooting with a D300 in med DX format. Shooting in FX mode, the med FX format jpeg file sizes should be close to 4 MB compressed.
#6. "RE: jpeg file size with D700" | In response to Reply # 3PaulBennett Registered since 09th May 2008Sat 27-Dec-08 06:56 AM
Compression isn't bad by nature, lots of compression is great for small images on the web. Tiff, bmp, jpeg, png, gif even RAW and DNG all use compression techniques.
It just that jpegs (and mp3 audio files for that matter) use a variable lossy technique whereby the image can't really be reproduced perfectly. I.e. in achieving a small file size they throw away a small amount of color and sharpness detail.
For this reason, every time you edit a jpeg, some quality gets lost. Saving it after the edit even to the best quality level, the image is degraded more but the file size is danged small.
Other file types are lossless but files are much larger. The nature of the technique used on jpegs take advantage of differences in the type and complexity of the image. That is why there is no hard file size answer.