How to fake long exposure photography without ND filters in Affinity Photo for iPad

Nearly three years ago I published a tutorial that showed a method I often used to create long exposure photographs in Photoshop without having used ND filters to actually capture a long exposure. This is a technique that I still use today when I find myself without a filter. However, with the bulk of my post-processing workflow now done with an iPad Pro, I’ve switched over to Affinity Photo to achieve the same effect.

As with the Photoshop version of this tutorial, this will all work by taking multiple short exposures to capture movement before merging them together into a single image via Affinity.

But here’s the kicker, it’s actually simpler in Affinity Photo than in Photoshop. The team at Serif have added in a Stacking mode directly from the New File screen, making the whole flow just a two click process. Nice, right?

Here’s What You’ll Need

Just three things, that’s all you’ll need.

A Tripod: Although it’s possible to align multiple images during the Affinity stack process, you’ll be wanting to make sure all shots within your sequence line up with each other. Don’t have one? Check out my review on the Sirui W-2204. This is the tripod I use for the majority of my work.

A Remote Shutter Release or Intervalometer: In order to get the perfect final image, you’ll want to eliminate all camera movement, shake and shutter release vibration. Although it’s more than possible than to do that without a remote shutter, it’s always worth using one, if available, to be on the safe side.

Affinity Photo for iPad: And of course you’ll need to have purchased Affinity Photo. Currently, if you don’t already have it, the iOS version will set you back a once-off purchase of about $30 AUD while the desktop versions are $80 AUD.

Taking The Initial Photographs

The goal here is to capture multiple shorter exposures, similar to the process of making a time lapse, which will then be used create the final image. There are a few things to keep in mind before going ahead and taking your photos.

Firstly, there’s no hard rule on just how many individual images to take. However, more images equals more movement. Use your best judgement to determine how many photos you’ll need based on the conditions when taking them. If you’re shooting the ocean and want perfectly flat water then you’ll need more images than say, shooting a scene with fast moving clouds.

If you want to get technical, you can calculate the number of individual photo’s to take in order to produce a long exposure of a specific time length. So, say you’re currently shooting at a shutter speed of 1-second and you want a 4-minute exposure. You’d need to take 120 shots with a 1-second delay between each.

Preparing The Sequence

I personally manage my catalogue with Lightroom, though you can import your photo’s directly to iCloud Drive or the Photos app.

Now, when it comes to Stacking in Affinity, you’ve got two options. You can either stack the unedited RAW files directly or you can save them all as a JPEG first. Keep in mind that the large the file size of each image, the longer the stack process will take. Due to this, I generally apply my edits in bulk and export them all as JPEG’s before the stack process. After stacking, I’ll then apply any additional adjustments as needed.

Stacking In Affinity Photo

Time to stack those photo’s.

  1. Open up Affinity Photo and click New (the plus icon in the top right corner) to begin a fresh document. On the following page, select the “New Stack” document type.
  1. The next page gives you a couple of options to select before uploading your image sequence. Here, you’ll want to make sure you switch “Align Source Images” and “Perspective Alignment” off. Being that the photo’s should have been taken with a tripod and remote shutter, there shouldn’t be any need to align the images. Additionally, these alignment settings can be a little buggy when there are things like reflections and bodies of moving water.
  1. After switching the alignment settings off, click on the iCloud or Photos icon to import your sequence. After the import they’ll appear within the “Images” box.
  1. Go ahead and click on “Ok” to begin the stacking process. This will take anywhere from a few seconds to a few minutes depending on the size of your images. Once it’s finished, you’ll be taken to the main workspace with a copy of your newly stacked images.

And that’s it. Now you’ll be able to apply a few final adjustments if required.

Before and after stacking

Not a bad process, hey?

There is one downside to doing this in Affinity though. It appears that stacks are capped at 50 images. This means, if you have a few hundred images you’re wanting to stack, you’ll need to do the following. E.g: Say you have 200 individual images:

  1. Follow the above process 4 times.
  2. Save each of the 4 long exposures.
  3. Then complete the above process but only stack the 4 newly created images.

Any questions? Feel free to get in touch.