HDRIBr?

So far so good. The flower is beautiful, but in its neutral environment looks almost like a painted on a wall, which isn't bad at all. I see you too have some tricks in the sleeve - very good use of the HDRI map. I wonder if the result achieved here will be that successfull in complex scenes. As Horo sais - keep up!

Square shadowof the sphere Rather lightlab - in fact I used 3 types of lighting: 1- "HDRI" skydome - responsable of reflections and (partially) of overall brightness of the image, 2- "Bulb" -single radial light - makes shadows, and adds slightly yellow tint to objects from right (here shadows turned max & soft), and 3 "Flashhlight" - four strong, but short ranged blueish-white spotlights from behind the camera - they emphasise flower and vase. It took 2(render) +7 hours (AA) on my Athlon 1800+ 1Giga memo. Without "Bulb" it renders much faster, but I wanted loooong shadows & caustics.

nice vase! Horo has already said everything. If you were to change the lighting angle, and change the ground plane from a plain gray nothing to something more realistic, it might help bridge the gap between your photographic content (hdr image) and your bryce content. Your work is always detailed and you have no fear of going that extra mile. Horo is so right describing your image as a very effective still life. I always ask this question, did you soften your shadows with the soft shadows setting in the light lab or with a light dome / ring? I am curious about the render time.

To answer the question on the image: definitely not. The directiopn of the light is wrong, hence the scene is not IBL lit - at least not by the ?hdri? used as it is reflected on the sphere. Otherwise - excelent picture. Nice stil life, well lit. You don't need fancy materials to make an effective piece of art. Good work, keep it up.