After processing each of my best photos to the maximum size TIFF that I believe they'll be good enough to display and sell,
I save each image's NEF and TIFF and assign numbers to each so I can quickly find them on my computer. I also create 72 dpi
680 pixel (at widest) JPEGs of each TIFF so I can quickly view them. Then, I copy (backup) everything to a second internal drive
and at least four external drives. Finally, I post the "best of my best" photos on my website. Yes, this is time consuming. But I
know all hard drives fail. TIFFs require a lot of hard drive space, especially with newer DSLRs, but I've found that it's advantageous
to keep them. Still, I only use 300 dpi JPEGs when ordering prints. I'd like to find a more efficient way to backup my images, but
my current system has worked well since 2005. Any suggestions?

WJShaheen did not make a comment, but I think what he was saying that the subject was Sony RX10 IV and a6500. Yes, well true, but once a camera, whatever the make or model, takes a 4K photo the procedure is the same. I believe that was the a5k subject... "how to make a still" Title of this thread.... "Stills from 4K video - a tip"

a5k did not give detail of how-2 and from his "tip" I went from there and captured an image. Now I know how and so do others.

WJShaheen, Am I wrong regarding the meaning of your comment; if so what was the meaning?

The details here apply to my Sony cameras, RX10 IV and a6500 but what I'm going to tell you should apply to any 4K video.

First I tried it in-camera, again, based on what is on the Gary Friedman book on the RX10 IV. It does work and is handy if you don't have a computer but unless I'm just not following his instructions correctly, the size of the JPG from a 4K frame is less than 3MB, not 17 as he describes.

I went back to using VLC which is an open source, any-platform video program. With that you can take a "snapshot" of a given frame and use its settings to decide on output format - JPG, PNG or even TIF. I'm not sure the huge increase in file size is worth it but the TIF is quite large -about 17MB in my case. More importantly, it can be edited with post processors such as CaptureOne. So can any format, but IMHO the best results come from the best starting point.

BTW, notwithstanding SONY's dire warnings, I copy the "clip" from the SD card to my SSD for further work. I have played video directly to a large screen TV when I travel (using HDMI) and it works quite well even though the TV is usually only 1080. It's a nice feature and doesn't need a computer at all.

Just tried it (VLC) and it works as described. Thanks for the tip. (With that you can take a "snapshot"...)


The SONY feature that allows you to capture stills while filming a video only works, as far as I can determine, when using normal HD, not 4K.

One issue you will face with a cropped sensor camera is that you really have to go wide to get a wide angle view. So, that said, my favorite two lenses for that camera are, the Nikon 10-20 and 12-24 f4. Nikon has a new inexpensive 10-20 that gets good reviews. On your camera the angle of view for that 10-20 would be 15-30 MM. Which, would give you lots of options. Below is a link to that lens. Good luck and keep on shooting until the end.
https://www.bhphotovideo.com/c/product/1341603-REG/nikon_20067_af_p_dx_nikkor_10_20mm.html?sts=pi

this is surprisingly easy to measure, although perhaps not to lab standards. However using the same process for all tests means that the results will be consistent with each other

set camera to high (or low) speed continuous. Use the image settings of your choice (JPEG, RAW, JPEG + RAW). Use a digital stop watch (on smartphone?) as the subject. manual focus (so no focus time delay).

press shutter for 1st stage (ie get ready for immediate firing of shutter)

Looking through the viewfinder, press and hold shutter as soon as stop watch reaches exact value such as 0s (this not as easy as it sounds :) - best to watch and count the seconds for 4 or 5 seconds to 'get into the rhythm',) then keep holding shutter on continuous shooting and release when you hear the shutter slow down or stutter (ie internal buffer is full, and camera must now copy to card).

Then - and this is the imprecise bit - watch the recording light on the camera and the stop watch, until the recording light goes out and note the time on the stop watch. Then you can easily calculate a lot of info:

* you pressed the shutter for the first frame on an exact stop watch value, but the first image will show a later time. The difference is the shutter latency for the first or a single frame. This can be surprisingly high. On one low priced DSLR camera I tested this was getting on for 1/2 sec! but remember it includes the quality of you pressing the shutter on an exact second.

* The difference between first and last frame number is the number of frames exposed before the shutter slows and effectively is the size of your camera buffer - I don't have exact figures to hand, and it may depend on memory card, but recall on my 6D I could take a maximum of 16 RAW before slow down. JPEG + RAW was less. JPEG only was well over 20 (again, depends on what JPEG 'quality setting you select.)

* After releasing the shutter, if you noted the time when the red recording went out after the camera finished copying from buffer to your card, the difference between that time and the time on the last image is how long the buffer take to transfer all the images. It is easy to calculate an approximate idea of the speed of the card in your camera, for a single or block of images, with your preferred image settings. I tested several different cards that I had at that time and found the Sandisk extreme Pro card to be the fastest of what I had by a good margin (not saying the SEP is the best card, but definitely best of what I had. There are obviously others as good but I worked with what I had.)

This test could easily be repeated with 1 card, then card 2, or both cards for a reasonable idea of the various card/s recording capabilities

If you just want to test standalone card faults / recording potential on a PC (don't know about Macs), then google and get h2testw and Crystal disk mark, both free. the former records a 1Mb file from end to end of the card then verifies it. Obviously a 100% pass is required. It also gives write and read (verify) times for the sequential 1MB file size. Crystal Disk Mark can be set up to test several things but for camera use I set a file size about equal to the size of RAW file I expect, then start a sequential write / read test to run for 5 or 10 minutes ie emulating the recording mode that I think probably happens in the camera (obviously not for that length of time for still images, but need a longish test to find reasonable averages for RAW.)

I test all cards with h2testw when I get them and then know there are no faults. Fortunately camera testing only needs to be done once :) But at the end of that I have excellent idea of which cards are best for performance with my use of a camera and know the read/write speeds with my environment. On a PC it is important to use a good quality card reader (USB3 in my case) and to insert into a native USB(3) slot in the PC. Be aware that some USB2 slots on older PCs may be slower than your camera. Also cheap card readers are surprisingly variable, and don't use a hub or extension cable as they can have a big impact on performance.

While I haven't used the D7200, I can tell you that I chose the D7500 for the sensor. It's the same sensor as D500, and while it's a slightly smaller image than the 7200, it's a much better photograph- in low light.
I shoot a lot wildlife, in the woods or at dawn where I need a 2000th of second. I upgraded from the D5600 and it's a very worthwhile upgrade.

If, on the other hand, you only shoot weddings, family gatherings, or mid-day scenes, you'll probably get the same images out of either camera. The 7200 is 2015 tech, and the 7500 2017 tech. That may mean something.