In Anticipation of Bugs to Come

[Don Hoey]

Originally Posted by wolfie

..........but just one point, especially when using a focus rail (screw/worm drive) you only need to establish your first point of focus, then depending on the thread size just give it 1-2 revolutions to obtain the varying focus points.

Harry

Harry,

That was the reasoning behind the micro adjuster I made. If I use a reversed 28mm then I loose auto diaphragm so multiple focussing ops would just be a pain. Todays effort was really for Lello's benefit so focussing was by lens only.

Don

[Don Hoey]

Originally Posted by andy153

- Still think its a bit pricey Harry - cannot deplete the D3 fund as I have a bad attack of NAS (Nikon Acquisition Syndrome) at the moment!!

Looking at your signature " Equipment: Nikon - D2x; D300; D2h; D200 - More than enough !!! "

Perhaps a revision required - Not quite enough !!!

Don

PS : When you have spent that bankroll you can save up for whatever the replacement for the D2X is called.

[Lello]

Hi Don
sorry I have Been busy, Well the experiment seems to have worked well using the focus only technique, I will try the same sort of thing over the weekend and let you know how I get on.
Lello

[andy153]

Hi Don - am holding fire as there are rumors of a D3x in August - FX format and 24mp plus the soup-up like the D2x to D2xs. Also there is the new D3p series with the extra picture control button on the body rather than in the menu.

[Don Hoey]

No bugs yet but experimentation continues.

I have tried a stack as large as 32frames now, but unlike Astro stacking where more is best, I have found this does NOT apply with CZM. 32 frames was a bit of a disaster when compared to a 9 frame stack from a selection taken from the same set of images.

As posted previously as focus changes so does magnification.
I have compared the difference between moving the sliding rail and refocussing the lens between shots. Refocussing the lens reduces the magnification difference between first and last frames significantly when compared to the sliding rail focussing method.
Two images attatched to show the difference.
Image 1 is an overlay from the sliding rail focussing method, of Frame 32 on Frame 1 from an earlier experiment. Zone of focus - bias weight to back edge of the head is 70mm.
Image 2 is an overlay from refocussing the lens method, of Fame 6 on Frame 1 of the attatched main image from the experiment.

Image 3 is the result of a stack of 6 frames with refocussing by way of the lens between shots. Zone of focus 80mm taken at f8.
Image 4 is a 100% crop from image 3 as an example of the accuracy of registration from the stacking program.

Hey ho, back to the drawing board to come up with a means of micro adjusting focus on the lens without having to peer through the viewfinder to determine the points.

Don

[Don Hoey]

Originally Posted by andy153

.......Also there is the new D3p series with the extra picture control button on the body rather than in the menu.

Sounds like thats worth a thread on its own ..... Nikon rumours.
I know I've been out of circulation for a few days, so where did this come from ??

Don

[Gidders]

Been meaning to have a play with this program since this thread went up & a wet Sunday afternoon seemed the right time.

Used my 70-300 IS lens with a Canon 500D close up filter. To judge my focus points I just stuck a sliver of post it note on the lens focus grip and another on the lens barrel marked out with the furthest & nearest points of focus and 5 intermediate positions, aperture set at f8

[Don Hoey]

Neat trick with the post-it note Clive, and the resulting image ........................ SUPERB.

Don