Thanks to an ultra-rare movement disorder, I have a lot of experience with shaky hands, among other fun stuff.
One of my first suggestions would be to let your doctor/specialist know tremors interfere with your photography/hobby/etc. I did, and the treatment/approach changed to focus on that activity. It’s one thing to say “I have tremors.” It’s another thing to explain how your tremors affect your day to day activities. Here is an example of my redacted visit notes.
Assessment and Plan
The following list includes any diagnoses that were discussed at your visit.
Assessment Note: [ltdbjd] is a —year-old male with —, and essential tremor. He continues to experience tremor in both hands, which is functionally limiting, particularly for fine motor tasks and activities such as photography …. The plan was to increase the — dosage to — mg up to — times daily as needed for tremor control, with the rationale that higher and more frequent dosing may provide more sustained symptom relief ….
I agree with everything everybody has included in this string. Things that were helpful for me include proper breathing. Take a deep breath in, let it about half-way out, hold your breath and depress the shutter. Some important points include not holding your breath for more time than it takes to depress the shutter (1 to 2 seconds). The longer you hold your breath, the more motion blur will be introduced into the photo. Another key point is to press the shutter release gently. Punching it, stabbing at it, etc. can move the phone and create blur.
Another helpful thing was to reduce how much I hold the phone or press the shutter release. Others mentioned tripods and other assisting devices and bracing. If I can’t do either of those for some reason, I use two hands and tuck my elbows in. I try to hold my phone/camera as lightly as possible. The tighter you hold it, the move motion blur you can expect.
People mentioned earbuds. Depending on your phone, you can set it to release the shutter with the volume button (and sometimes to burst mode for multiple photos with one shutter release). This will also work with the volume buttons on earphones, and keep you from stabbing the phone or moving it while pressing the shutter button. That said, I’ve never tried earbuds to take photos. Another suggestion is to use the timed shutter release. Set up the phone, set the timer (2 seconds, 5 seconds, etc.), and let it release the shutter without you manually touching it.
Speaking of bracing, if you look at most of my observation photos, there aren’t many photos looking straight down at something. Most are taken at some degree of an angle. This is because I set my phone or small camera (TG-6) on the ground to brace it, lean it forward, and then take the photo(s). I took some of the higher angles by stacking things up and resting the camera on the stack. Some of the higher angles pointing downward were taken with me stacking something up and setting my phone on the stack. These are attempts to limit my contact with the phone/camera and to create a steady base.
For example:
https://www.inaturalist.org/observations/387349650
https://www.inaturalist.org/observations/385777710
https://www.inaturalist.org/observations/385163559
Of course, this is fairly easy to do when most of your close up observations are dead insects on the ground. It certainly won’t work for everything.
Speaking of stacking, my phone is probably too old to do this with, but I’ve found in camera focus stacking to be amazing at limiting motion blur. I haven’t looked into it, but there are likely third-party apps that let you focus-stack from a camera. My first experience with in-camera focus stack was with the used TG-6 I bought a few months ago. Note that in-camera focus stack is different than using Helicon or Zerene stacking software.
Another tip is to speed up the shutter. The faster the shutter, the less motion blur you’ll have. You can accomplish this a few different ways. One is with light control. The more light you have, the faster the shutter speed. This can be natural light, or a small LED light. Another is with shutter priority. Depending on your phone, you might need a third-party phone app that lets you set a shutter priority. In this mode, you determine how fast you want your shutter to actuate, and the camera/phone sets the other things for you (aperture and ISO).
I imagine there are bluetooth shutter releases as well. I have them for my cameras, but have never used one for my phone.
Keep in mind that digital zoom magnifies not only the subject being photographed, but it magnifies hand movement too. Use it as sparingly as possible. The more tips in this thread you follow, the more leeway you’ll have to zoom. One option is to take the photo from farther away and crop the photo. You lose pixels and can end up with a less detailed/sharp photo, but it may be preferred to a blurry photo. Along the same lines, you can shoot in 4K video in good light and pull a sharp frame or two for your photos. I’ve never done this myself.
I understand there are some AI software programs that help reduce motion blur in photos that have been taken. I’ve never used them, so I can’t speak to their effectiveness.
Hope my/our experience can help others!