Great job. You can see how far you’ve already come from the first photos you’ve taken. The last batch, and in particular the Green Terror, are excellent. What kind of off camera flash are you using? Some have a setting that will allow you to adjust the spread of light coming out of the flash head. Consider buying a diffuser. Sounds like you were already doing that by pointing the flash into a cooler. Putting the flash on top of the tank was the right move. There are lots of diffusers, my suggestion would be a Gary Fong Lightsphere...about $40. It helps focus the light, but also diffuses its delivery.
Sounds like you have a workaround to achieve the black background. Snapseed is a great ap. I use it all the time with my Iphone shots. DSLR’s use through the lens (TTL) metering. Your camera can change how that is applied by changing the focus options. The factory setting uses points across the entire frame. This takes in both the subject and the surroundings. You can dial down how much your camera is considering by changing to spot focus. That means it uses the fish...or whatever you are focusing on...to send the appropriate amount of light from the flash. Depending on your settings (ISO, aperture nd shutter speed) this will give you a leg up on the black background. What’s happening is that your camera is recording the image from the flash and ignoring the ambient light in the tank.
Suggestion above is solid. Start shooting in RAW. Change the settings in the camera to shoot RAW along with Fine JPEG. It will give you two images. The short explanation is that a JPEG‘s are compressed files that contain fewer data than RAW. RAW files contain all of the dignitable information that your camera is capable of recording. Way more latitude on what you can do with an image.
Keep up the good work. You‘re off to a great start.
Sounds like you have a workaround to achieve the black background. Snapseed is a great ap. I use it all the time with my Iphone shots. DSLR’s use through the lens (TTL) metering. Your camera can change how that is applied by changing the focus options. The factory setting uses points across the entire frame. This takes in both the subject and the surroundings. You can dial down how much your camera is considering by changing to spot focus. That means it uses the fish...or whatever you are focusing on...to send the appropriate amount of light from the flash. Depending on your settings (ISO, aperture nd shutter speed) this will give you a leg up on the black background. What’s happening is that your camera is recording the image from the flash and ignoring the ambient light in the tank.
Suggestion above is solid. Start shooting in RAW. Change the settings in the camera to shoot RAW along with Fine JPEG. It will give you two images. The short explanation is that a JPEG‘s are compressed files that contain fewer data than RAW. RAW files contain all of the dignitable information that your camera is capable of recording. Way more latitude on what you can do with an image.
Keep up the good work. You‘re off to a great start.