Huge enlargements?

jerry12953

jerry12953

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Jeremy Moore
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I've had an enquiry for an image to blow up to 5.3 m wide on a "pub staff-room wall".

While the client considers the images i'm wondering if there's anything I can do to increase the file size for optimum quality. Is it called "up-rezzing"?

And if so how does one do it? I have an old version of Photoshop (CS2), Affinity Photo and lightroom.

And i'll probably be posting about quoting a price as well..........
 
Yea you can do it yourself in Photoshop.

You've already got the dimensions so that's a start, so just go to Photoshop > Edit > Image Size, and set the width to 5.3 Meters (or equivalent).

If you let Photoshop resize the image without doing any resampling, it will probably reduce the resolution to 50 Pixels/Inch or something....this might be fine considering it's such a major enlargement, but you may want to limit the Pixels/inch to something like 100. In that case, Photoshop will need to do some resampling (processing to fill in the extra pixels).

Note that you can't just set the PPI to 300 and enlarge to 5.3M wide and expect magic detail to appear, but what I've never been able to get to the bottom of is at what point resampling stops being effective and lowering the PPI is a better option. I even asked the question on the forum and basically the answer was "try both and see which looks better"...probably not an option in this case :D

EDIT: Just seen you are using an old version of Photoshop...but I would imagine the process is the same, although you may want to stick to not letting Photoshop do any resampling as I don't know how good the old algorithms are.
 
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Andy Into The Wild said:
EDIT: Just seen you are using an old version of Photoshop...but I would imagine the process is the same, although you may want to stick to not letting Photoshop do any resampling as I don't know how good the old algorithms are.
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I wonder if Affinity would be a better option. Am exploring their help files at the moment.......

sk66 said:
Topaz AI Gigapixel
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I wonder if i could do it using a free trial of that.........
 
jerry12953 said:
I wonder if Affinity would be a better option. Am exploring their help files at the moment.......



I wonder if i could do it using a free trial of that.........
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They offer a free trial for 30 days (or at least they used to) so well worth giving it a try.

As long as your other editing programs can accept really large images because a 2x enlargement means a four fold increase in the MB size and 3x means a 9 fold increase.
 
petersmart said:
They offer a free trial for 30 days (or at least they used to) so well worth giving it a try.

As long as your other editing programs can accept really large images because a 2x enlargement means a four fold increase in the MB size and 3x means a 9 fold increase.
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Is that the case even if dropping the resolution of the enlarged file?
 
Andy Into The Wild said:
but what I've never been able to get to the bottom of is at what point resampling stops being effective and lowering the PPI is a better option.
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Resampling never stops being "effective," the question is whether it's actually beneficial... A human cannot even see 300ppi/dpi at a distance of over 2ft (I forget the exact numbers now).
The only thing normal (bicubic) resampling really does is to break the large squares (pixels) into smaller squares (more pixels) so you do not see the squares when printed. AI Gigapixel is a different animal entirely...
 
sk66 said:
AI Gigapixel is a different animal entirely...
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AI Gigapixel is a total break from normal resampling in that the intelligence behind it was trained on millions of photographs and "knows" what something should look like.

It can also add in detail which may not have been in the original if it "decides" that is what should be there.

When I tried it out on a picture of a girl in a dress, some of the fine detail in the weave of the dress was missing in the original due to diffraction but Gigapixel added in a kind of cross stitch pattern, which, although it didn't actually match the original weave, did make an attempt to improve the original and I only caught it because I was actually looking for it.
And I can only see more and more programs based upon AI becoming more and more prevalent and even better because it certainly looks as if ordinary algorithms can no longer achieve everything we want them to.
 
Andy Into The Wild said:
Yea that's what I thought, which is why I was surprised it would increase the file size so much as petersmart suggested.

I have to look into AI Gigapixel, it sounds interesting!
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But don't forget there's no such thing as a free meal, and if you use Gigapixel you also need to have decent lenses as it may also show any shortcomings with your lenses although it claims to offer some correction for noise and blur.

But the ability to turn a Canon 200mm f2.8 zoom into a 400mm or 600mm zoom is incredible, especially since in that case there is no loss of aperture.

And the saving in weight and COST is amazing!

And I know it does increase "reach" because of my own experience with it.
 
Just changing the DPI won't have any effect, this variable is usually ignored on printing, the print being made to the size requested. There will be no difference in file size as the data doesn't change apart from number in the print resolution field.

To print big you need more data, Ideally at least half a million pixels wide for a 5.3m wall (that's still less than 300dpi). I would expect anything much less than 100000 pixels wide (~50dpi) to look blocky

Gigapixel looks impressive but it only claims to work up to 6x, so you'll still want to start with 20,000 pixels wide - way more than my cameras can manage.
 
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I wonder if AI is going to come up something which lets ordinary computers behave like very big powerful computers?
 
chris malcolm said:
I wonder if AI is going to come up something which lets ordinary computers behave like very big powerful computers?
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I highly doubt it (at least in the near future)....what people call AI isn't really AI, it's more like predictive analytics where huge amounts of data is fed into it and a likely outcome is determined based on previous results. The only way that could work in the way you suggest is for a program to get more efficient at what it's doing over time, thus reducing it's hardware demands, but it still is limited within the hardware it's operating on!

That said, it is amazing what computer programs can do!
 
jerry12953 said:
Have looked at the system requirements for Gigapixel and I'm almost certain that my system won't support it. So I can cross that one off my lost of possibilities......
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It looks like my feeble 5+ year old PC at home could just meet the barest minimum requirements for CPU based operations (earliest compatible windows version, 8GB RAM max for motherboard, unsupported graphics, they don't list CPU specs but mines - dual core 2.6GHz - not impressive even for when I brought it)
From the sound of things I'd have to max my RAM & it will probably take most of the trial period to do a single image, No doubt it would probably crash as soon as anyone tried touching the computer for anything else too!

My sons (gaming) PC sounds like a much better bet... I might be able to make use of that - it's not like he does any work on it! ;)
 
Petrochemist said:
It looks like my feeble 5+ year old PC at home could just meet the barest minimum requirements for CPU based operations (earliest compatible windows version, 8GB RAM max for motherboard, unsupported graphics, they don't list CPU specs but mines - dual core 2.6GHz - not impressive even for when I brought it)
From the sound of things I'd have to max my RAM & it will probably take most of the trial period to do a single image, No doubt it would probably crash as soon as anyone tried touching the computer for anything else too!

My sons (gaming) PC sounds like a much better bet... I might be able to make use of that - it's not like he does any work on it! ;)
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I'm quite certain that a dual core definitely wouldn't cut it because my 12 core Z800 (dual Xeon 5690 CPUs) and 96GB RAM would still take some time on each photo and all cores went to max.

In the end I bought a Nvidia GeForce 1050 ti 4GB and that is fairly quick so your son's gaming computer could cope if it has a decent GPU on it.

But you could still try your own machine because I have run Gigapixel on a 1GB GPU and a 2GB GPU and it does work but slowly.

Oddly the 2GB card would crash at anything over a 2x upscale but the 1GB card could go higher without crashing.

But bearing in mind that there are TRILLIONS of operations on each upscale you can understand why you need something fast!

Or a lot of time.
 
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A pub had one of mine images printed on wallpaper to temporarily brighten up the pub before a full refurb. Original file was 11,000px wide so 45ppi at 6m wide, I up-scaled in photoshop to twice the size and it came out a lot better than I expected.

I only have a mobile photo of it though as an example.

Cefn-Mably-Hotel-Wall-Display-of-Penarth-Pier-at-Night-2.jpg
 
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jerry12953 said:
It does look a bit noisy!

But that's 11 Mp.
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No 11000 wide is much more than 11MP.
A 12MP MFT sensor is 4000x3000, 11000wide on a 3:2 ratio (typical DSLR) is 11000x7333 or ~80MP

Of course the image is probably actually a stitched panorama, at the roughly 5:1 ratio it looks like it works out 11,000 x 2,200 or about 24MP
 
Petrochemist said:
No 11000 wide is much more than 11MP.
A 12MP MFT sensor is 4000x3000, 11000wide on a 3:2 ratio (typical DSLR) is 11000x7333 or ~80MP

Of course the image is probably actually a stitched panorama, at the roughly 5:1 ratio it looks like it works out 11,000 x 2,200 or about 24MP
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Ok, thanks, I misread Johnsy's post.
 
johnsy said:
A pub had one of mine images printed on wallpaper to temporarily brighten up the pub before a full refurb. Original file was 11,000px wide so 45ppi at 6m wide, I up-scaled in photoshop to twice the size and it came out a lot better than I expected.

I only have a mobile photo of it though as an example.

Cefn-Mably-Hotel-Wall-Display-of-Penarth-Pier-at-Night-2.jpg
Click to expand...

I did enjoy Penarth Pier when I lived in Cardiff in the late 80s; not the grandest, but it has style
 
Talk to the printer, explaining that you want as high a quality as possible in the final product.
 
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