Size penalty from Nik filters

[DanK]

This morning I noticed a TIFF file in one directory that was 866 MB. It was an image that I'm not sure I will ever use. I opened it and found that it contained mostly adjustment layers that wouldn't add much size, as well as some cloning done on a blank layer. However, there was one additional layer in which I used Nike Color Efex to add tonal contrast.

Out of curiosity, I deleted that one layer and saved the file again. The size decreased by more than 2/3, to 266 MB.

I expected a size penalty, maybe close to a doubling, but I certainly didn't expect this big a difference.

[Manfred M]

No surprise at all there Dan.

Nik generates a new pixel layer and that by itself can easily double the size of the image, especially if the rest of the adjustments are adjustment layers, those tend not to have a significant size impact.

I also believe that the native psd file format uses lossless compression. The new layer that the Nik software adds (my experience here is mostly with Color Efex), tend to be more complex and in my view likely to compress as efficiently as the original image. This could be where the additional size of the final file comes in.

[DanK]

No surprise at all there Dan.

Nik generates a new pixel layer and that by itself can easily double the size of the image, especially if the rest of the adjustments are adjustment layers, those tend not to have a significant size impact.

I also believe that the native psd file format uses lossless compression. The new layer that the Nik software adds (my experience here is mostly with Color Efex), tend to be more complex and in my view likely to compress as efficiently as the original image. This could be where the additional size of the final file comes in.

Just to clarify: I store in TIF rather than PSD format. I use ZIP rather than LZW compression because tests have shown LZW not to be consistently effective with TIF files (it can actually increase size), and I use ZIP rather than RLE for layer compression because Adobe says it creates smaller files. However, I don't know of any way to control what Nik is doing internally with the additional layer it creates.

Since Nik is creating a new pixel layer and adding adjustments within that layer, I assumed that the increment in size--assuming there is nothing else in the stack that creates new pixel layers--would be roughly a doubling.

[Manfred M]

My understanding is that an Adobe psd file is based on the TIFF format.

I just ran a test on an image; a nominally 36MB image. The actual raw file is 43.9MB.

1. Saved file as a TIFF without any edits using TIFF, with zip compression - File Size 180MB

2. Used Nik Color Efex Pro (added a gradient, used Pro Contrast Filter and used Detail Extractor filter). This created a new layer and the combined file size (with both layers) is 616 MB as a TIFF with zip compression.

3. Deleted the original image layer and only saved the Nik created layer, again as a TIFF with zip compression - file size - 409 MB.

These numbers align nicely with the results you have been getting. My third version suggests that the Nik manipulated file does not compress as well as the original file without any manipulation. I have not used any other layers in this exercise, i.e. no adjustment layers, etc.

[DanK]

These do seem consistent with what I saw.

However, I just ran three similar test and got very different results. What I found is that TIF images with zip compression but with no edits whatever were not much larger than the original raw files. The largest difference was an increase of about 30%.

These became 3.5-4 times as large when I added a single color efex layer with only two adjustments.

So, the bottom line with respect to Nik is the same, but I don't understand why your initial conversion to TIF increased file size by a factor of 4.

So now I wonder: why was your initial TIF so much larger than the raw image?

[Manfred M]

Dan - frankly I can never figure out why the file sizes end up being what they are.

The Photoshop psd file ends up at 206MB for the first example; whereas the TIFF is 186MB. There is obviously some additional overhead in the psd file.

[billyb1191]

Agree with the opinion above