How to transfer highest possible resolution from iPhone to PC

[Rufus]

My web searches leave me very confused on this topic, and I wonder what others may have chosen as a workflow.

I have an iPhone and use the Photos app and built in camera along with iCloud Photos. Some of the camera lenses offer up to 48 megapixels, although that may not be relevant.

I don't want to process the images on the mobile device. Instead I use Photoshop on a Windows 11 PC. When I open HEIC format files (are these the sames as HEIF?) Adobe Camera Raw works as expected but I find when I open the file in Photoshop, it shows up as 72ppi, i.e. only suited to screen viewing.

Two questions arise:

1. How can I import the photos to the PC at the highest possible resolution?

2. How do I convert a file to, say, 300 ppi. Should I use Image Size and Interpolation and should this be done before or after editing?

Some say they can print large images from an iPhone, but presumably not from 72ppi images. I would not wish to print above A3 size.

[whited3]

David,

I often process SWMBO's iPhone 13 pro photos in PS. I get her to use RAW as this gives me the best options for PP.

Provided she remembers to set the Phone to RAW (!) I simply copy the dng files to my W10 PC, browse them in Bridge and open them into ACR as 16 bit, 300 ppi.

Here's a recent example.

As shot ISO640, f1.5, 1/40.
The dng file is 4032 x 3024, 19 MB.
The edited tif file is 4032 x 1713, 40 mb, 300 ppi.
This is an exported jpg.

[DanK]

Generally, ppi has no bearing on file size. That is an output measurement, for printing. Digital images have no physical dimensions, such as inches.

What you should check is the image size in pixels. If that is small, then you have a problem. If not, everything is as it should be.

[Rufus]

Thank you Dan and Mark for your replies.

Test image
I have created an image with my latest iPhone Camera app settings. While I have sufficient storage capacity I am retaining full resolution photos on the phone.

In the Photos App I note the following.

Image dimensions:4284 x 5712 pixels
File format: HEIC
File size:3.7 MB

I then signed in to iCloud Photos where full resolution versions are stored. I then downloaded it to my PC where I noted the following in File Explorer.

Image dimensions:4284 x 5712 pixels
File format: HEIC
File size:3.53 MB

My download method in iCloud Photos was to select the file and choose the More ellipsis button (top right) > choose More Download Options > choose Unmodified Originals.

When I open the image with Bridge it skips Camera RAW and opens directly in Photoshop which shows the image dimensions as 4284 x 5712 pixels (72 ppi).

I am hoping this method has imported the full resolution image with as little processing as possible, albeit not as a dng file or via Adobe CAmera RAW.

Editing the downloaded image
Assuming I may wish to print the photo, should I edit the downloaded image at the 72ppi image size and then upscale it or upscale the image before editing?

[DanK]

When I open the image with Bridge it skips Camera RAW and opens directly in Photoshop which shows the image dimensions as 4284 x 5712 pixels (72 ppi).

I think that's the answer. Again, anything with "per inch" is irrelevant at this stage, that is, to see whether you have the full size image. All that matters is the dimensions in pixels, which are the same, so you should be fine. Ignore the 72 dpi.

Assuming I may wish to print the photo, should I edit the downloaded image at the 72ppi image size and then upscale it or upscale the image before editing?

No. Edit it as is, without up- or downsizing it. You only want to downsize at the printing stage, and only enough to fit the native resolution of the printer. If you use an epson, it's 360 dpi. Canon is usually 300 dpi, but you can set the high-end printers for more. So, for example, if you want an 8 x 10 with an epson printer, you would want 2880 x 3600 pixels. I print from Lightroom, but I think photoshop allows you to set this manually or to have the software do it. You should set the printer resolution for whatever its native default is, not 72 dpi.

[lunaticitizen]

I'm surprised Photoshop can process HEIC files. I read that the format offers a bit more flexibility compared to JPEG but I never bothered to check.

[DanK]

HEICs are better: more compression, less loss of image quality. See https://www.adobe.com/creativecloud/...c-vs-jpeg.html.

[lunaticitizen]

Yes, I think that was the article I read.

My camera supports HEIC output natively, and I did consider using the format. However,
- My primary image sharing site (Flickr) doesn't support storing HEIC natively
- No browser except Safari supports native rendering of HEIC
- Lightroom doesn't support HEIC for its output

Therefore, I concluded it doesn't make any sense for me using the format. I continue using raw plus JPEG as the output of my camera.

[Manfred M]

While HEIC has a number of technical advantages over JPEG (this standard was established in 1992) whereas HEIC was formalized in 2015.

The main issue with HEIC is that the key technology is covered by patents held by entities like Apple, Adobe, Nokia and some of the camera manufacturers. That means anyone using the format needs to licence the technology from multiple sources, which means only the large players have the resources to do so.

This reduces the universal acceptance of this technology until such time that the patents expire.

Sure, go ahead and use it, but remember to switch to JPEG when posting and distribution your images so that others can access them.