Cokin’s NOT SO Neutral Density Filter

A few nice all your testing images I found:

Cokin’s NOT SO Neutral Density Filter
all your testing
Image by brentbat
Recently I bought a ZPro creative filter system. I bought 3 Singh Ray Grad ND filters (which are fantastic), and I also bought a Cokin 3 stop ND filter.

I’ve been perplexed by this awful candy pink colouring that has been coming through and this morning while shooting I did some tests. It’s definitely the Cokin ND filter (or not so Neutral) as is the case.

The image on the left shows the awful colour cast that this filter is putting on my images. The image on the right was taken immediately after I removed the ND filter. All processing has been identical on both images.

Anybody else found this problem or do you think I might have got a bad filter? I can’t believe how bad the colour cast is!!!!

Oh… and don’t critique the photo… it’s just a test print.

ThE GrEEn FaCeS…
all your testing
Image by Rosa Dik 009 — catching up !
If you have a good imagination, you’ll find more faces on this turning over picture……pleace notice, if you can…))
Thanks to all for your visits, comments and invites !!!
Have a splendid week ahead !!!

Ares I-X Rocket Launch: Bow Shock (NASA, 10/28/09) [Explored]
all your testing
Image by NASA’s Marshall Space Flight Center
A bow shock forms around the Constellation Program’s 327-foot-tall Ares I-X test rocket traveling at supersonic speed. The rocket produces 2.96 million pounds of thrust at liftoff and goes supersonic in 39 seconds. Liftoff of the 6-minute flight test from Launch Pad 39B at NASA’s Kennedy Space Center in Florida was at 11:30 a.m. EDT Oct. 28. This was the first launch from Kennedy’s pads of a vehicle other than the space shuttle since the Apollo Program’s Saturn rockets were retired. The parts used to make the Ares I-X booster flew on 30 different shuttle missions ranging from STS-29 in 1989 to STS-106 in 2000. The data returned from more than 700 sensors throughout the rocket will be used to refine the design of future launch vehicles and bring NASA one step closer to reaching its exploration goals.

Image credit: Scott Andrews, Canon

Editor’s note: Are you wondering "What’s a bow shock?" I was. Here’s what I found, courtesy of Wikipedia:

"A bow shock, also called a detached shock, is a curved, stationary shock wave that is found in supersonic flow past a finite body. Unlike an oblique shock, the bow shock is not necessarily attached to the tip of the body. Oblique shock angles are limited in formation based on the corner angle and upstream Mach number. When these limitations are exceeded, a bow shock occurs instead of the oblique shock. Therefore, bow shocks are often seen forming around blunt objects. In other words, when the needed rotation of the fluid exceeds the maximum achievable with an oblique attached shock, the shock detaches from the body; hence beyond the shock the flow-field is subsonic so the boundary condition can be respected at the stagnation point.

The bow shock significantly increases the drag in a vehicle traveling at a supersonic speed. This property was utilized in the design of the return capsules during space missions such as the Apollo program, which need a high amount of drag in order to slow down during atmospheric reentry."

en.wikipedia.org/wiki/Bow_shock_(aerodynamics)

Original image: mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=43954

More about Ares I-X: www.nasa.gov/aresIX

p.s. You can see all of the Ares photos in the Ares Group in Flickr at: www.flickr.com/groups/ares/ We’d love to have you as a member!

Leave a Reply

Your email address will not be published. Required fields are marked *