Get more realism out of product renders?

I need to get these product renders to the point where people look at them and wonder whether it’s a render or not. Like Estee Lauder product renders. They are so god damn realistic I still can’t tell if they’re rendered or not.

They look okay, and realistic enough to be used internally for visualization purposes but I’m not happy enough with them to put them into our catalogs and use on our website.

Obvious Problems:
-Texture distortion on tubes
-No straw showing up in the Hand & Body Cleansing Gel Pump? There’s a straw in it, not hidden and for some reason it’s invisible?
-The liquid doesn’t really seem like it’s having the right type of distortion on the top.
-The distortion of the liquid is totally hiding the straws on the Linen Spray and Fragrant Body Mist. It shows up on the top half and disappears on the bottom half
-Black line on the Hydrating Body Cream Pump? Keep getting this problem. I can usually fix it by shrinking the liquid inside.

  • Lacking general realism. Like I said, it’s kind of realistic in a way, just doesn’t seem real. Lacks that convincing feel.

Short and to the point…

Honestly for a catalogue job this is good enough if you fix the straw and texture distortion.
Especially the cosmetics industry really likes unrealistic overstylized hyper-clean renders.

If you want to improve it for like portfolio purposes i would suggest working on the liquids and their viscosity.
Different liquids will have different refraction/reflection indexes as well as different dielectric boundaries between the liquid and the air (your black line in the body cream bottle)

For the disappearing straw, maybe you need more transparency bounces, but im not sure whats going wrong there.

It looks good, but the most obvious problem to me is a lack of contrast. The entire image is very washed out and seems overexposed. I might suggest rendering without the background and add it back in Photoshop, or pushing it further away from the products to keep the light bounce minimal. The black line on the Body Cream is due to your camera height being set to the same height as the level of the liquid. Maybe you can adjust the camera or raise the level of liquid so that it appears more full? For the non-transparent portion of the bottle, maybe play with various glass shader setups. Can you post an image of the node setup you are using? Maybe it is casting a shadow, which can be eliminated.
Depending on where your ad is going, I would recommend making the border of the image larger. In case this gets printed, you want to make sure there is plenty of area around the bottles that can be cropped out. For pring the image should have the ability to be full-bleed on a standard full page spread.
Lastly, use an aftermarket photograph post-processing software after using blender for color correction. Overall tone, gamma, contrast, etc. can be easily adjusted to your liking. Blender really just does not cut it. I would recommend using Adobe Lightroom. It is relatively easy to learn and used by many professional photographers. Doing this type of visualization, it gets a bit tricky because you have to master 3D visualization as well as photography.

For the straws, one main thing comes to mind: Is the liquid the same IOR as the straw?
I don’t know if this is true in the products you are advertising for, but I think it might look good if you added some roughness to the straws. Again with the lighting, the photos you mentioned in the original post look like they were lit with two wing lights and very little back-lighting (almost as if they were rendered with a black background). That might look good in this photo as well.
For getting the correct liquid distortion on the containers, make sure the liquid turns up a little right around the edges (Make sure you capture the total internal reflection!)