if I upgrade to ios10 will photoshop CS4 stop

El Capitan may not be available anymore for download from the App Store if you hadn't downloaded it previously. You will have to go to Sierra.

For what it's worth Photoshop CS3 is working as well with Sierra as it did with El Capitan for me. There may be some features that do not work but all those I use work fine. You will, however, have to reinstall Java for OS X 2015-001 again before it will work.

I have Photoshop CS3 and it's working fine with Sierra as it did with El Capitan, Mavericks, Yosemite and earlier systems. There may be some features that don't work but all of them that I use work fine. You could get an external HD and install Sierra on it to run and test whether your various apps will work before you upgrade you primary boot drive to Sierra.

Remember that you will have to download and install the Apple legacy Java from here, Java for OS X 2015-001, in order for Photoshop to run.

Also check RoaringApps.com to see if any of your 3rd party Apps have been discussed regarding Sierra.

What model of Mac do you have and how much RAM is installed?

I would call your local Apple Store, first, to see if they can install an older OS X version, first.

This is ability for stores to do this is on a store by store basis.

Just so you know, you can continue to use iPhoto on Yosemite, but it is long unsupported by Apple.

You may need to run all of the iPhoto updates to get to the last version of iPhoto that is still compatible with both OS X Yosemite and El Capitán.

Apple created a new photos app simply called Photos that supercedes iPhoto. now.

Good Luck!

All of Adobe CS4 will work reliably on OS X 10.8.5 Mountain Lion, OS X 10.9.5 Mavericks.

Most CS4 apps (including Photoshop CS4) still work on OS X 10.10 Yosemite.

Adobe Photoshop CS4 is the only Adobe CS4 app tha is still fully functioning under OS X 10.11.6 El Capitán.

No Adobe CS4 apps will function under the new macOS Sierra.

I am using Adobe CS4 Design Premium under 10.6.8, 10.8.5 and 10.9.5 with no issues.

Before embarking on a major OS upgrade, it would be wise, advisable and very prudent if you have a good,working backup of your current system to an external connected and Mac formatted Flash drive OR externally connected USB, Thunderbolt or FireWire 800, Mac formatted hard drive. Then, use either OS X Time Machine app to backup your entire system to the external drive OR purchase, install and use a data cloning app, like CarbonCopyCloner or SuperDuper, to make an exact and bootable copy (clone) of your entire Mac's internal hard drive. This step is really needed in case something goes wrong with the install of the new OS or you simply do not like the new OS, you have a very easy way/procedure to return your Mac to its former working state.

Then, determine if your Mac meets ALL minimum system install requirements.

To download and install either the pay OS X 10.8.5 Mountain Lion or the free OS X 10.11.5 El Capitán (if it is even still available now because Apple just released the free macOS Sierra) you need one of these Macs:

OS X 10.8 Mountain Lion purchased emailed download code here.

http://store.apple.com/us/product/D6377Z/A/os-x-mountain-lion

Apple will send you an email for the special download code for the Mac App Store, for OS X 10.8.5 Mountain Lion within three days of purchasing the download code.

iMac (Mid-2007 or later)

MacBook (13-inch Aluminum, Late 2008), (13-inch, Early 2009 or later)

MacBook Pro (13-inch, Mid-2009 or later),

MacBook Pro (15-inch or 17-inch, Mid/Late 2007 or later)

MacBook Air (Late 2008 or later)

Mac mini (Early 2009 or later)

Mac Pro (Early 2008 or later)

Xserve (Early 2009)

Your Mac also needs:

OS X Mountain Lion, Lion, or Snow Leopard v10.6.8 already installed

2 GB or more of memory (I strongly advise, at least, 4 GBs of RAM or more)

8 GB or more of available space

Next,

If you run any older Mac software from the earlier PowerPC Macs, then none of this software will work with the newer OS X versions (10.7 and onward). OS X Snow Leopard had a magical and invisible PowerPC emulation application, called Rosetta, that worked seamlessly in the background that still allowed older PowerPC coded software to still operate in a Intel CPU Mac.

The use of Rosetta ended with OS X Snow Leopard as the Rosetta application was licensed to Apple, from a software company called Transitive, which got bought out, I believe, by IBM and Appe could no longer secure their rights to continue to use Rosetta in later versions of OS X.

So, you would need to check to see if you have software on your Mac that maybe older than, say, 2006 or older.

Also, check for app compatibilty here.

http://roaringapps.com/

If you have any commercial antivirus installed and/or hard drive cleaning apps installed on your Mac, like MacKeeper, CleanMyMac, TuneUpMyMac, MacCleanse, etc. now would be a good time to completely uninstall these apps by doing a Google search to learn how to properly uninstall these types of apps.

These types of apps will only cause your Mac issues later after the install of the new OS X version and you will have to completely uninstall these types of apps later.

Once you have determined all of this, you should be able to find the latest versions of OS X by clicking on the Mac App Store icon in the OS X Dock and then login to the Mac App Store using your Apple ID and password and if you purchased a download code, input that code.

You can then begin the download and installation process of installing the newer versions of OS X from the Mac App Store.

Good luck!

You can still iPhoto (you may have to manually update versions from the Apple website because your Mac is 3 OS X generations behind to OS X 10.10 Yosemite) to get to the Yosemite compatible version of iPhoto.

Do a search on the Apple website. Use the search terms

iPhoto downloads

If you want to explore the new Photos app, I am just suggesting you manually make another copy of your iPhoto library folder for the new Photos app to use, so you are not stuck using it if you feel you may not like.

I have years of images saved and organised in iPhoto based on how iPhoto works.

The Photos app destroys a good chunk of the organisation.

There are other issues with the Photos app that I , also, do not like nor appreciate about it.

I think that Photos as an Apple Photo app has been really "dumbed down" from the way iPhoto has worked for years and years.

Also, Apple ended support for Aperture, which I also use, and there is no longer any integration with Aperture with the new Photos App and, as usual. Apple has not designed an alternative for Aperture.

Once again, leaving pro and semi-pro users out in the cold.

Here is a complete description of the recent Apple Photos app for OS X Sierra.

http://www.apple.com/macos/photos/

See what you think of it. Everyone is different. I don't like it. You may!

While cloning will make a copy of everything, it is only one copy.

Make another backup copy of the iPhoto library folder, you'll end up with two copies and put in elsewhere.

If you find you like the new Photos app in Yosemite, you can delete the copy later on.

I only mention my own circumstances and decisions for example.

I'm sticking with older OS X versions for other reasons of my own, as well as, for software compatibility as I am no longer a full-time professional an can no longer afford to upgrade/update my critical software, any longer.

SuperDuper will work fine for creating a bootable backup of your entire system.

Good Luck!

I am a heavy Photoshop user and had the same doubts regarding Adobe CS4 running with the new Sierra. (With Yosemite and El Capitan the CS4 suite operated smoothly and without any problems. ) For a worst case scenario I checked Time Machine and all my backups, so I could reboot El Capitan if necessary. Since I don't like Adobes Cloud subscription I also checked for possible Photoshop alternatives and found Affinity Photo for Mac very tempting.

https://affinity.serif.com/de/ After that I felt pretty safe and updated to OS Sierra. Once installed, I also downloaded Java for OS X Download Java for OS X 2015-001 which, as I understand it, is needed to run the Adobe CS4 suite. After that I tried Photoshop, InDesign and Dreamweaver - and all apps work seamlessly with OS X Sierra on my iMac. (iMac (Retina 5K, 27", end 2015 with Fusion Drive). So essentially my workflow stays about the same as before. However, I think that I will start working more and more with Affinity, replacing Photoshop CS4 step by step.

If OS X 10.11.6 El Capitán is no longer available for download, forget getting macOS Sierra.

Adobe CS4 will, in all likelihood, no longer function.

Your only other option is to pay for the download code and install OS X 10.8 Mountain Lion if my link is still active to order it.

If you have a local Apple Store, that is within a reasonable driving distance, you could call that store , ask for the Genius area and find if they can download and install OS X 10.9.5 Mavericks for you, instead as the current iTunes version for new iDevices needs a minimum OS X of OS X 10.9.5 Mavericks.

That and there are some issues now with running OS X 10.8.5 Mountain Lion.

Specifically, older Safari is no longer being updated, nor supported and the last fully updated and supported version of Mozilla Firefox (vers. 48.0.2) is soon ending support for users still running OS X 10.6-10.8

You can get an older version of Mozilla Firefox version (vers. 45.x), called Firefox ESR, that is only getting security updates (NO new feature updates any longer) until next April 2017

The only other OS X 10.8.5 supported web browser is called SeaMonkey.

Search for

SeaMonkey project.

Good Luck!

I wonder why most of Adobe CS3 is still working under El Cap while really only Photoshop CS 4 is the only fully functioning app under OS X 10.11 El Cap.

Back this past Jan., I got an educational, full, legai version (not an upgrade version) of the Adobe CS4 Design Premium Edition for real cheap from a independent seller on Amazon because I thought Adobe CS3 was kaput on both OS X 10.9 Mavericks AND OS X 10.10 Yosemite.

I looked at roaring apps and most of Adobe CS3 seems to be still operational up to OS X El Cap.

Strange that!

I am glad I was able to obtain a newer Adobe CS4 fairly cheaply where I don't feel like I could have just stayed with Adobe CS3.

😉

There are some features that were reported in another topic that don't work. As I didn't use them I didn't pay much attention to them. I've not used any Actions recently so don't know if some of them might be incompatible.

Once CS3 stops working I'll begin using my Photoshop Elements. The only thing it doesn't have that I occasionally but rarely use is converting an image to CMYK. For that I can use GraphicConverter.

You will need to install more RAM.

Running OS X 10.10 Yosemite or El Capitán plus Photoshop (which you should be running with no other apps running, anyways) requires, at the very least, 8 GBs of RAM or more.

Officially, your 2011 iMac can take 16 GBs of RAM.

Unofficially, up to 32 GBs of RAM can be installed and has been fully tested for compatibilty and operation.

I would seriously think about installing 16 GBs of RAM.

Apple seriously overcharges for RAM and RAM installation.

It is far cheaper to order the proper Mac RAM from a proper, online source and install it yourself.

Correct, proper and reliable Mac RAM can ONLY be purchased from online RAM sources Crucial memory (crucial.com or OWC (macsales.com).

https://eshop.macsales.com/shop/memory/iMac/2011/DDR3_21.5_27

RAM is relatively easy for novice users to install

https://eshop.macsales.com/installvideos/imac_mid_2011_mem/

Good Luck!

mac0S Sierra would have been OS X 10.13.

It is now simply called macOS Sierra.

As I stated to the previous Poster here, ALL of Adobe CS4 runs on OS X 10.10 Yosemite.

Only Photoshop CS4 is the only Adobe CS4 app that is fully functioning under OS X 10.12 El Capitán.

You will still need to install more RAM no matter what OS X you upgrade to.

What app are you using to backup your data to that MyBook drive?

If you are using OS X Time Machine app, then your external drive has no bootable OS X on it.

OS X TIme Machine only backs up apps and data and current system states.

Time Machine does not create a bootable drive.

On the Roaring apps website, the green color means that app runs with no issues under whatever OS X version column.

Yellow means the app functions under an OS X versions, but has some issue/s and problem/s.

Red means the app has stopped working under a certain OS X version.

Blue means that there is no user data to confirm whether or not an app works or doesn't work under a version of OS X.

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