There is a way to observe spin, if not to measure it. Use a marker pen and put four big, black 15mm dots on the ball, at the vertices of a tetrahedron (i.e. equally spaced around the ball). It's quite easy to observe the spin, and tell whether it's heavy or super-heavy. Try this with different balls and see if you can see the difference. You'd probably need something like one of those high speed Casio cameras to actually quantify the spin, but it'd be interesting to see if you can actually perceive a difference without the camera.

Iskandar

Just an update after, perhaps, half a dozen sessions using the DHS D40+ ball at my local TT club: Zero broken balls, zero cracked balls! Easily the most durable TT ball I can recall using. The rough coating lasts an admirably long time but they do start to smooth out after 20h or so, which is entirely OK by me! Even my Nittaku-only friends have warmed up to the DHS D40+.

oh, i soooo wanted to like these....for all the above reasons...

but i hate them

you can throw all the advantages that the ball have out of the window bcs, i cant get past the one, for me, big flaw....and that is, there is simple not enough rotation...

even seamless balls have more rotation than this one...it was absurd...the player that i beat easily last season, both wing looper i have lost this time in 5 sets, only bcs of the ball...for ppl that dont know me, i am playing with frictionless anti...when i blocked his heavy spin last season with a different ball, the underspin was so hard he hit his knee lol...and when we played last weak with d40 he missed it alright, but this time it went long over the net bcs he was overcompensating since he expected there was more underspin on it...when he adopted it was all over...he could spin on my anti 5 or 6 times in a row...

and it was not only me...my teammate who is playing with 2 inverted could not win a point from the serve, and he have great serves...

all of that could be that is bcs of my anti i am not liking it...but i also dislike it for my fh...bcs the ball is not spinning enough, when i wanted to attack a heavy underspin with a strong spin, the ball didnt have a trajectory to overcome the net...it was going in a straight line...and if i compensate and hit it higher it went long...

the ball is good only for flat hitters, or for ppl that are looping higher less risky balls... anyone whose game consists around a spin or spin variations is not going to have a fun time with this ball...

i had resold the balls immediately and dont want to see them again

all above is just my personal opinion and experience with the d40 ball, dont attack me for it pls, i see a lot of ppl like it...

I didn't like them at first either, thinking I couldn't generate any spin. But stick with them, I think it's just a question of timing which will come after a couple of sessions.

i am using xiom vega china...as sort of alternative to h3n...so in no way a rubber that cannot produce rotation...

and i dont want to get use to them...i could play with them, but them i would have to change my whole game, put SP on bh etc...

i am using xiom vega china...as sort of alternative to h3n...so in no way a rubber that cannot produce rotation...

and i dont want to get use to them...i could play with them, but them i would have to change my whole game, put SP on bh etc...