Photoshop brush requirements for good print

Could you help me? I want to make 20x16 in photoshop print poster 300 dpi and need to use brushes , but I think some brushes are not enough quality.I am begineer at photoshop but I need to know what I must know about brushes to get enough quality for 20 in size photo 300 dpi for good print

Are you talking about brushes that come as OEM in Photoshop?
I don’t know about the quality of brushes found out in the wild but anything in the program will work at whatever resolution you set the image at.

My motto has always been: “When in doubt print it out.” Print it out in scale on a decent quality photo paper.

But here’s another question. How are you getting these printed? Because if I were printing a 20" x 16" photographic print on photo paper using a high quality RGB laser exposure unit and wet processing it, I’d suggest 200ppi, unless it’s a high end art print, in which case I might recommend 400-600ppi - but you’d be paying a big premium for that kind of output. It takes longer in machine time to print. I’d more likely suggest 200ppi at the slower speed on the machine. You wouldn’t pay anywhere near premium on that.

If you are getting these printed digital inkjet… depends on the machine but 150-200 would be plenty for the larger presses I use, but maybe 300 is standard for the smaller ones. Can’t say.

Anyhoo, When in Doubt Print it Out works for most things. If you see stuff you don’t like in the print, check your output settings first, then check the brush detail.

And just for the record, even though you probably arent doing this, if you are printing out of InDesign, there is a goshdarn hidden little drop-down menu in the print dialog under Graphics>Images>Send Date that used to default to “Optimized Subsampling” No. You want to send “All”
Looks like they fixed that in the 2020 release that I just checked here, but not 100% certain of that. And Indesign menu selections often remain stuck.
But I go off topic here…

Thank you,I am trying to start print on demand business. I want to sell digital files and trying to figure out all the dimensions I need. I have bought some great brushes years ago and your info is really helpful.I think I need to find the way to checkout how much is the dpi for brushes I have. The sizes to fit it the image sizes. But if I have a brush created in 300 dpi, I also need to know sizes of it.Am I right? (If it is 2400x 3000 px I can create only 8x10 inches in 300 dpi not 16x20 inches.So it is problem ) .
I really want to understand standards ,because I won’t have possibility to know about printing machines my clients are going to use,I think. So as I understood it really depends on practise as you said.

Not sure of your business model here. If these are things people are gonna print out on their home printers, 150ppi is adequate. Though not many are gonna have 16 x 20 capability.

Or are you talking about stock imagery here that you intend to license out.

As for the brush, are you covering that entire canvas with one brush stroke? I don’t think so. The brush will be smaller, with a higher resolution. Since it never really occurred to me that brushes were limited in resolution I had a look around. The largest brush tip you can make in Photoshop is something like 2500x2500 pixels. That’s an 8"+ wide brush at 300ppi. If you make the brush tip smaller, the resolution should scale up. So a 4" brush would be 600ppi, a 2" brush would be 1200ppi and so on. At least in theory.
Now what happens to the integrity of the brush stroke itself? That depends on the brush. It could change significantly with size change.

When in doubt print it out.

Thank you. I want to use print sites as platform to sell digital prints . They will do it on canvas and other materials. I wish to aware general rules for big size prints too. To advice customers opportunity to choose different sizes.even much bigger than 20x16inches. I got stuck in some problems. like 300dpi maybe it is almost impossible for big sizes to maintain it for big size prints. Also I think I need 16 bit and Cmyk mode as I understood. I know I can ask Webpages about their requirements, but it always seems helpful for me to know general rules, I think.

so even if I use my brushes in 20 in size image, brush size itself will be enough to be 300 dpi even I use it 8in size .Am I right.

I Think I’ve got the answer. Thank you so much.You helped me.

If these are being printed on “canvas” you don’t need to be above 200ppi at 16" x 20". But if you want to give the option to print larger, you have to go bigger. As you know, enlarging photoshop images reduces the output resolution in proportion to the scale.

You don’t need 16 bit but you can use it.

And depending on how sophisticated the printer is, some want Adobe RGB or ProPhoto RGB. That gives there rip (the raster image processor) more color information to translate into CMYK using the custom ink profile for the specific canvas media you have. Once you dumb down an RGB image to CMYK and save it, that extra color info is lost forever. Some of the high end art print machines have a far wider color gamut than your standard CMYK print machine. Some of them even have Orange, Green and Violet inks to widen the gamut even more. With those, you’d get more vibrant color if you start in a larger color space. Bear in mind though that you can do things in the RGB color space that don’t translate well to standard CMYK.

Side note: The default RGB color space in photoshop is sRGB which has a relatively small gamut that already falls mostly within the CMYK gamut. When creating a new document, you should check your color profile. Don’t be satisfied that it says RGB, you need to look at the tip arrow and select either Adobe RGB or ProPhoto if you are doing Art. Later on, if you need to save to CMYK for an upload spec, ask what profile to apply and save a copy of your Art. But it is often better to have the output house apply their own custom profile. You aren’t likely to have any of the manufacturer’s profiles for the machines and inks used for this kind of printing.