Can I get a custom size?
No. Sizes are a fixed set, and each exists because a verified production route exists for it. The largest was re-cut for that reason.
No. The sizes are a fixed set rather than an arbitrary dimension you can request, and each one exists because a verified production route exists for it.
That cuts both ways, and the honest version includes the part that is inconvenient for us.
The constraint is real, not a policy
Each size maps to a specific production setup. Introducing a new one is not a form field — it needs a verified route for every material, and until that exists the size cannot be made regardless of who asks.
The largest piece is the clearest example. It was originally specified at 20 by 30 inches, which turned out not to be a producible size, and it was re-cut to 20 by 28. The catalogue conforms to what can actually be made rather than to what sounded good.
And metal is not offered at the largest size
The same constraint applies within a size. At 20 by 28 the only substrate available is paper — metal is not produced at that dimension, so the largest piece is paper only.
That is not a preference. It is the same table, read from the other direction.
What happens if a size cannot be fulfilled
It is refused rather than substituted. The mechanism exists specifically so that a product outrunning what can be produced fails loudly instead of quietly shipping the nearest available size to somebody's house.
Receiving a 16 by 20 when you ordered a 20 by 28 is a worse outcome than being told before you paid.
Why not just offer everything
Because every additional size multiplies rather than adds. A new dimension needs a verified route for paper, for canvas and for metal, and each of those is a separate production setup with its own proofing.
A catalogue that offers every size offers most of them untested, and the customer who discovers which ones were untested is the one whose print arrives wrong. A short list that is entirely producible is a better object than a long list that is mostly theoretical.
Choosing within the set
The useful question is not which size you want but which size your photograph supports, which is a different question and usually has a narrower answer. From there, the material changes what suits — covered in paper, canvas or metal.
Current sizes and prices are on the catalogue.