Saving images to a smaller size on the Z7?

[DRwyoming]

Oh ok, the smaller raw files do reduce pixel count. Are they usually somewhere between full resolution and DX mode. DX seems to roughly cut the full res in half.

That's not a great comparison because whether shooting in full frame (FX) or DX crop mode you still have the option of saving the Large raw, a Medium raw or a Small raw file and the pixel dimensions reduce for those medium or small raw files accordingly. Here's a summary of the Z7 II image sizes in pixel dimensions for shooting in the various raw modes but also for varying in-body crops including DX:

Z 7II

• [FX (36 × 24)] selected for image area:
  • 8256 × 5504 (Large: 45.4 M)
  • 6192 × 4128 (Medium: 25.6 M)
  • 4128 × 2752 (Small: 11.4 M)
• [DX (24 × 16)] selected for image area:
  • 5408 × 3600 (Large: 19.5 M)
  • 4048 × 2696 (Medium: 10.9 M)
  • 2704 × 1800 (Small: 4.9 M)
• [5:4 (30 × 24)] selected for image area:
  • 6880 × 5504 (Large: 37.9 M)
  • 5152 × 4120 (Medium: 21.2 M)
  • 3440 × 2752 (Small: 9.5 M)
• [1:1 (24 × 24)] selected for image area:
  • 5504 × 5504 (Large: 30.3 M)
  • 4128 × 4128 (Medium: 17.0 M)
  • 2752 × 2752 (Small: 7.6 M)
• [16:9 (36 × 20)] selected for image area:
  • 8256 × 4640 (Large: 38.3 M)
  • 6192 × 3480 (Medium: 21.5 M)
  • 4128 × 2320 (Small: 9.6 M)

IOW, selecting image area (FX, DX, 16:9, 1:1, etc.) is one thing and then deciding how to save that image as a raw file (Large, Medium, Small) is another thing and then to add to that you can chose: Uncompressed, Lossless Raw Compression, Lossy Raw Compression or JPEG and of course you can chose either 14 or 12 bits for the raw files (JPEGs are always 8 bits per pixel).

So there's a lot of options and combinations that can be used to select pixel dimensions and crop area as well as how the file is saved and how much memory it takes up on a card or disk.

And just to be clear the cropping options actually crop the image which leads to ideas like 'crop factor' or 'reach' for how the angle of view of a given lens changes with the crop but the Medium and Small raw saves use the full frame or whatever crop you have dialed in so going to the Medium or Small raw files do not additionally change the crop factor beyond whatever full frame or crop you have dialed in.

 

[Mr. Goodkat]

I keep about 1 to 5% of the photos I take. For this reason, space hasn't been much of an issue.

Workflow suggestion:
If you like to keep many photos and don't want them to take up much space, a possible solution would be to shoot RAW+JPEG. You would keep the RAW files of the best photos and the remaining would be JPEGs.

I just started shooting with raw+jpeg. I didn't really get why someone would want to but after shooting raw all the time I can see it now. As long as the white balance and color profile are chosen correctly I can see why it's nice to let the camera do the work and provide a jpeg good enough for a simple photo. But then the raw files are available for those one or two photos that might require more advanced action in post.

That's not a great comparison because whether shooting in full frame (FX) or DX crop mode you still have the option of saving the Large raw, a Medium raw or a Small raw file and the pixel dimensions reduce for those medium or small raw files accordingly. Here's a summary of the Z7 II image sizes in pixel dimensions for shooting in the various raw modes but also for varying in-body crops including DX:

Z 7II

• [FX (36 × 24)] selected for image area:
  • 8256 × 5504 (Large: 45.4 M)
  • 6192 × 4128 (Medium: 25.6 M)
  • 4128 × 2752 (Small: 11.4 M)
• [DX (24 × 16)] selected for image area:
  • 5408 × 3600 (Large: 19.5 M)
  • 4048 × 2696 (Medium: 10.9 M)
  • 2704 × 1800 (Small: 4.9 M)
• [5:4 (30 × 24)] selected for image area:
  • 6880 × 5504 (Large: 37.9 M)
  • 5152 × 4120 (Medium: 21.2 M)
  • 3440 × 2752 (Small: 9.5 M)
• [1:1 (24 × 24)] selected for image area:
  • 5504 × 5504 (Large: 30.3 M)
  • 4128 × 4128 (Medium: 17.0 M)
  • 2752 × 2752 (Small: 7.6 M)
• [16:9 (36 × 20)] selected for image area:
  • 8256 × 4640 (Large: 38.3 M)
  • 6192 × 3480 (Medium: 21.5 M)
  • 4128 × 2320 (Small: 9.6 M)

IOW, selecting image area (FX, DX, 16:9, 1:1, etc.) is one thing and then deciding how to save that image as a raw file (Large, Medium, Small) is another thing and then to add to that you can chose: Uncompressed, Lossless Raw Compression, Lossy Raw Compression or JPEG and of course you can chose either 14 or 12 bits for the raw files (JPEGs are always 8 bits per pixel).

So there's a lot of options and combinations that can be used to select pixel dimensions, crop area as well as how the file is saved and how much memory it takes up on a card or disk.

Wow that's a lot of options. I can understand why some just choose not to worry about the storage methods and just shoot for maximum data captured.

The Z7 would be nice for the higher megapixel count but I'll have to decide if that's important enough to bump the Z6II from the top of my list.

 

[DRwyoming]

The Z7 would be nice for the higher megapixel count but I'll have to decide if that's important enough to bump the Z6II from the top of my list.

When faced with a similar decision I opted for the Z6 II mostly for its low light capabilities and I don't really chase the highest pixel resolution in cameras nor crop a ton.

BTW, here's the equivalent image sizing chart for the Z6 II:

Z 6II

• [FX (36 × 24)] selected for image area:
  • 6048 × 4024 (Large: 24.3 M)
  • 4528 × 3016 (Medium: 13.7 M)
  • 3024 × 2016 (Small: 6.1 M)
• [DX (24 × 16)] selected for image area:
  • 3936 × 2624 (Large: 10.3 M)
  • 2944 × 1968 (Medium: 5.8 M)
  • 1968 × 1312 (Small: 2.6 M)
• [1:1 (24 × 24)] selected for image area:
  • 4016 × 4016 (Large: 16.1 M)
  • 3008 × 3008 (Medium: 9.0 M)
  • 2000 × 2000 (Small: 4.0 M)
• [16:9 (36 × 20)] selected for image area:
  • 6048 × 3400 (Large: 20.6 M)
  • 4528 × 2544 (Medium: 11.5 M)
  • 3024 × 1696 (Small: 5.1 M)

 

[John Woodworth]

This may/may not answer your questions re Z7ii, since it is for the D850, but here goes:

Photographic Dynamic Range versus ISO Setting - Nikon D850 Special Edition

Many thanks for this link. Very interesting. It seems that 12RawM gives the best dynamic range on the D850. I would have thought that would be the 12RawS based on the model in my head...More pixels to average. So more left to understand.

 

[DRwyoming]

Many thanks for this link. Very interesting. It seems that 12RawM gives the best dynamic range on the D850. I would have thought that would be the 12RawS based on the model in my head...More pixels to average. So more left to understand.

This is an even older deep dive into what Nikon was and wasn't doing in terms of the downsized raw images. There's some discussion in here about why pixel binning would be a good approach but at least when this was written it wasn't what Nikon was doing. This is a very old article so I wouldn't try to map it directly to what Nikon is doing now but what I don't know is how much Nikon changed their downsampling approaches in the Z cameras.

sRAW Format Explained

photographylife.com

 

[EricBowles]

One thing to keep in mind with many Nikon cameras is you can get most of the benefit of a smaller file simply by shooting 12 bit RAW rather than 14 bit RAW. It's probably the first choice to make because as your ISO goes up above ISO 320 or 400, there is no value of shooting 14 bit Raw. I prefer to use Lossless compressed 14 bit most of the time for simplicity.

As you move to the new Z9 and later cameras, the options are changing. Nikon has a new High Efficiency mode in two versions - they maintain image dimensions in pixels, but change compression to reduce the file size. These modes are 14 bit only.

 

[John Woodworth]

This is an even older deep dive into what Nikon was and wasn't doing in terms of the downsized raw images. There's some discussion in here about why pixel binning would be a good approach but at least when this was written it wasn't what Nikon was doing. This is a very old article so I wouldn't try to map it directly to what Nikon is doing now but what I don't know is how much Nikon changed their downsampling approaches in the Z cameras.

sRAW Format Explained

photographylife.com

Very useful. When I searched their site I used the wrong keywords. Thank you. Based on this article I would be wary of any non-standard compression until otherwise analyzed by independent experts.

One thing to keep in mind with many Nikon cameras is you can get most of the benefit of a smaller file simply by shooting 12 bit RAW rather than 14 bit RAW. It's probably the first choice to make because as your ISO goes up above ISO 320 or 400, there is no value of shooting 14 bit Raw. I prefer to use Lossless compressed 14 bit most of the time for simplicity.

As you move to the new Z9 and later cameras, the options are changing. Nikon has a new High Efficiency mode in two versions - they maintain image dimensions in pixels, but change compression to reduce the file size. These modes are 14 bit only.

Thank you. Yes. Photographylife concludes that the old Nikon sRaw formats (D810 specifically) are marketing BS (my words).

 

[DRwyoming]

Based on this article I would be wary of any non-standard compression until otherwise analyzed by independent experts.

Yeah, when I see terms like 'virtually lossless compression' my suspicion index rises. Virtually Lossless is basically an oxymoron, it's either bit perfect and lossless or it's a lossy compression technology. Sure the lossless algorithm could be good enough for any practical use and that's what the in depth reviews and field testing could show but that's when I'd trust something like that and not when the manufacturer first uses terms like that in their sales pitch.

 

[EricBowles]

This is evolving. They started with Lossless and I've heard that lossless means that no data is lost but it it compressed. Virtually Lossless means something else, and it's probably okay to have an imperceptible amount of data loss. The Z9 has something called High Efficiency * - and Ricci explained that as a level of compression and some minor data loss but at a level where he could not visually observe the loss (but he had not fully tested it yet).

There are several places where they can compress files or reduce file size without affecting the NEF. The Nikon files have RAW data, IPTC and other metadata, and three separate JPEG files. Those files are a large JPEG for a 100% view, a Basic JPEG for thumbnails and routine playback, and a medium view that is somewhere in between. The JPEG files could be compressed with lossy compression or even reduced in size and it would make no difference to the RAW file. I don't know the size of these JPEG files, but would not be surprised if they were 15 MB, 5 MB, and 1 MB or something similar with the possibility of anywhere from a little to a lot of compression. Nikon has already cut file size for uncompressed Z7ii files by changing the way the data is packed. Essentially they were putting 14 bits of data and two bits of zeros into 16 bits of storage, and now the data is being written in a manner where the null data is not being stored at all in the uncompressed file.

 

[Mr. Goodkat]

A question about editing higher pixel photos, lets say 40+ megapixels. Are they much slower to edit because of the extra data? I've read that a faster and more powerful computer makes things easier. Does they extra data or details in the photos make it that much harder to process them? Is the difference negligible?

 

[DRwyoming]

A question about editing higher pixel photos, lets say 40+ megapixels. Are they much slower to edit because of the extra data? I've read that a faster and more powerful computer makes things easier. Does they extra data or details in the photos make it that much harder to process them? Is the difference negligible?

The extra data in high resolution files doesn't make the processing steps any more difficult but yes for a given computer it will be slower to process a very high resolution file a opposed to a lower resolution file of the same bit depth. But sure, a faster computer with more memory, and a large and fast scratch disk can speed things up enough that it's not a problem but still a lower resolution image file will generally be faster than a high resolution file with all that extra data.

In my experience tools like LR and PS are pretty fast for general editing on say 20 megapixel or 45 megapixel files but if you start doing things like large layer stacks (e.g. star trails or focus stacking) or use some slower aftermarket tools like some of the Topaz products the slow down for bigger files becomes more apparent.

 

[EricBowles]

A question about editing higher pixel photos, lets say 40+ megapixels. Are they much slower to edit because of the extra data? I've read that a faster and more powerful computer makes things easier. Does they extra data or details in the photos make it that much harder to process them? Is the difference negligible?

I agree - if your computer is reasonably current the file size does not make much difference. For me, the big difference shows up when you have 4+ image panoramas - not single images. Focus stacks always take a while, and longer with a high resolution camera. I have a new Dell XPS 15 with 32 GB of RAM and it's fine processing images from the Z7ii.

To give you a sense of volume work, I just finished a job involving taking 3000 images, rating every image, identifying selects, and importing those images to LR. Then I edited 800 images individually in LR and exported as JPEG's. The entire process took less than 36 hours from the end of shooting time - and there was another client shoot during that time. Total editing time was about 5 hours for 800 images.

 

[Mr. Goodkat]

I agree - if your computer is reasonably current the file size does not make much difference. For me, the big difference shows up when you have 4+ image panoramas - not single images. Focus stacks always take a while, and longer with a high resolution camera. I have a new Dell XPS 15 with 32 GB of RAM and it's fine processing images from the Z7ii.

To give you a sense of volume work, I just finished a job involving taking 3000 images, rating every image, identifying selects, and importing those images to LR. Then I edited 800 images individually in LR and exported as JPEG's. The entire process took less than 36 hours from the end of shooting time - and there was another client shoot during that time. Total editing time was about 5 hours for 800 images.

That makes sense and I'm sure my laptop would be up to the task even though it's 16 gigs of RAM and not 32. It's doesn't struggle with any of the Adobe programs but yes, the few times I did some stitching it took an extra minute or so to complete the task.

I was toying with the idea of selling my D7500 and a few other things to fund a used or refurbished Z7 but I still think the best move might be to keep my D7500 and still go with the Z6II. Forty plus megapixel probably isn't necessary for my photography at this point.

 

[John Woodworth]

I agree - if your computer is reasonably current the file size does not make much difference. For me, the big difference shows up when you have 4+ image panoramas - not single images. Focus stacks always take a while, and longer with a high resolution camera. I have a new Dell XPS 15 with 32 GB of RAM and it's fine processing images from the Z7ii.

To give you a sense of volume work, I just finished a job involving taking 3000 images, rating every image, identifying selects, and importing those images to LR. Then I edited 800 images individually in LR and exported as JPEG's. The entire process took less than 36 hours from the end of shooting time - and there was another client shoot during that time. Total editing time was about 5 hours for 800 images.

Thank you for this real data point.

I am also using an XPS 15. I think that my turn-around would be 36 hours for about 700 snaps so your efficiency is, as always, impressive.

I am previewing in LR, but have Fast Raw Viewer which I have never used. Do you use something like this? Should I switch over?

 

[EricBowles]

Thank you for this real data point.

I am also using an XPS 15. I think that my turn-around would be 36 hours for about 700 snaps so your efficiency is, as always, impressive.

I am previewing in LR, but have Fast Raw Viewer which I have never used. Do you use something like this? Should I switch over?

I use Photo Mechanic for the front end of my workflow. It's much faster than Lightroom because it uses the embedded JPEG in the RAW file. I rated 2000 images in two hours following my shoot, and the remaining 1000 images the next day. Then I reviewed my 1000 4 rated images to finalize my selects for editing.

Photo Mechanic is especially good for high volume workflow. I use it for ingest and it handles renaming, captions, titles, copyright data, etc. It is not an editor, but is good at applying watermarks or any metadata as a watermark. For example, I can label images for a presentation with shooting data on an automated basis.

Fast Raw Viewer is a good alternative, but PM does a bit more for the higher price. I've been using it about 13 years.

 

[JohnW]

Storage these days is pretty cheap. I shoot raw and in the largest bit depth available. Still have every digital image since started shooting digital back when the D100 was introduced and before that scanned files from the Coolscan LS-20 from when I was shooting film with the Nikon F Ftn and the F90. When I went from the HP to Apple G5 moved all my images and documents from the internal HD to External HD. 1st with Lacie then GTech and now a combination of GTech and the Samsung SSD's. I find treasures in some of those old files and with an advancement in processing tools or my own knowledge find that I'm able to bring out new life to an old image that was never able to in the past.

With all my newer images from the D800, Z7 and Leica Q2 located on the Samsung SSD, find that processing is very quick and only time it slows down is when using Topaz sharpening.

I might lower the bit depth if I was out in the field and was reaching my cards capacity and didn't have a spare. Other han that would shoot in the largest space and bit depth available.