Very complex background removing

[lotems17792987]

hi, im working on urchins photos and im trying to cut them out of their backround. i tried with the channels to remove it, but it didnt go well.

can anyone tell me how to do it prefect?

thank you

[Norman Sanders]

Another approach for this image is to experiment with Image > Calculations to create a mask. In the sample above, the Calculations was followed by a Curves adjustment and brushwork In the center of the object. 

[lotems17792987]

hi, thanks for helping..that what i tired to do in the picture above, its just dosnt come clean as i wished for in this way

[rayek.elfin]

Why not just use a selection path with a slight softness to it to cut out these subjects? Takes a couple of minutes, but any automated method will need a lot of cleanup anyway. Our eyes are much better in this case.

Here is a rough version I managed in two minutes. Added a quick drop shadow with a mask as well. (Drop shadow needs more work, though). Used NIK Sharpener to add more contrast and detail.

[lotems17792987]

hi! thanks for your answer, can you explain me how to do the shadow with the mask? im thinking maybe to work hard with the pen tool, and then adding the shadow because it looks much better  this way

[rayek.elfin]

Actually, I used the pen tool to create the layer mask for that example. The drop-shadow is just a copy of the original, with a layer effect overlay with black,, converted to a smart object to which  I then added a layer mask and a gaussian blur filter. I then used the brush with black to get rid of the unwanted shadow parts at the top and sides, and used a light grey brush in the layer mask to adjust the shadow a bit. I did that bit very quickly, so it's okay-ish, but not that great looking yet.

And I used Google NIK Sharpener to add more texture and focus.

[Omar.Fathy]

or you can try it using Pen Tool.

[Barbara Ash]

How important is it to you to get a really clean selection to knock out the background? If it is very important, use Omar.Fathy's suggestion, the Pen tool.

The Pen is time-consuming, but there's not enough contrast to get a truly clean selection using any of the other methods, and any other method will require a fair amount of tedious cleanup afterwards.