Wess AHX500K 35mm slide mount, initial impressions

Discussion in 'Digital Darkroom' started by mendel_leisk, Oct 22, 2005.

  1. I've just received my order of Wess AHX500k 35mm slide mounts, after
    considerable delay: the order was made in late August, through
    Adorama. The price for a box of 50 was $14.95US. And of course, the
    price was eclipsed by the shipping charge. (I've got to quit ordering
    single items.) A current search of the Adorama site for "ahx500"
    returned no hits. A search for "wess" returned a few hits, but not
    these mounts. The same applied on the B&H site.

    The box indicates manufacture date 05/13/05. Also on the box, the
    website: "www.wessmounts.net" is noted. This site has some further
    contact info, for direct ordering. It also indicates the slides were
    made in Ronkonkoma, New York. Inside the mounts is the embossed
    statement "MADE IN USA BY WESS PLASTIC TEL 516 231-6300".


    Some description and initial impressions of the mounts, scanning with
    Minolta Scan Elite 5400 (first generation):

    (In all descriptions the mount is landscape oriented, hinge at top,
    open to receive a slide chip.)

    The mounts are a one-piece design, hinged at the top, clasp at the
    bottom. The opening appears to be exactly 36mm by 24mm. I don't have
    an inside caliper to verify, just careful measure with a ruler. The
    opening is slightly larger than the Gepe "full frame" mounts. The
    closed thickness is slightly under 2.5mm, micrometer measured at
    several points.

    On the bottom half of the mount, behind the top edge of the 24x36
    opening, is a row of (roughly) square pegs, one for each film
    sprocket hole. There is a similar row of pegs along the bottom edge
    of the opening. The latter, however, are rectangular, and snug fit
    for the corresponding film sprocket holes. The outside face-to-face
    of these two rows of pegs is such that when the film chip is pressed
    down onto the pegs, it is positively pulled into tension. On the top
    half of the mounts, flats and depressions dovetail with the pegs
    opposite them.

    There is also a small round pin, halfway up each side on the bottom
    half, with corresponding holes on top half.

    I have been placing the chip loosely in the bottom half, pressing it
    onto a central peg or two on both rows, just sufficiently to hold it
    in position, then pressing the mount shut.

    At this point, the slide chip is like a miniature drum. The
    topography of the film from center of bottom edge, across the middle,
    to center of top edge, is virtually level, as measured with Vuescan
    manual focus. As are all the edges. The weak link is a bit of doming
    at the left and right edges, but very subdued. Also, I suspect my
    slide holder's platen is slightly off perpendicular from the
    scanner's lens, but close enough that shimming is not practical or
    needed.

    My usual last step before feeding in my Elite 5400's slide holder is
    to give both sides a blow with a bulb blower. With these mounts, the
    blower creates is distinctly different sound. There is a "thrumming"
    tone, similar the resonance you get by lightly tapping a drum skin.

    Here's my results of doing a few Vuescan manual focus measurements
    (positioned per their location on the landscape oriented image):

    -.623*********-.564*********-.594

    -.641***-.652**-.558**-.658***-.641

    -.644*********-.658*********-.670

    The scans reflect these numbers. The edges and center are usually
    equally sharp. Any "errant focus" areas are typically near the left
    or right edges, in the corner as often as not, minor, and small in
    area.

    With the Gepe mounts I tried previously, I could do my best to focus
    manually, bring the bar display of focus so that both were extended
    equally, then wait 30 seconds, and see the black bar fall back,
    apparently indicating the slide is flexing as it warmed. With the
    Wess mount, this does not happen.

    Getting the slide chip out of the holder is moderately difficult, but
    get's easier with practice. The first hurdle is unlatching the bottom
    center edge. A little flexing of the edge helps with this. Then the
    film itself is locked, solidly, on the posts. I've found a thin
    needle slipped under a lower left corner, then pushed along at
    shallow angle, breaks it loose, one post at time. The whole chip can
    then be broken loose from the top row of posts in one movement with
    the use of tweezers.

    Before using the mount, a close look-over is worthwhile. There are
    occasional little extra flaps of plastic at mold lines. My main
    concerns are any on the backside, which might throw the slide of-
    level in the platen,, and the occasional "blip" in the 24x36 opening.
    Both are easily removed with an exacto knife.

    Well, I'm going to continue to test these. Also of great interest to
    me, someone has generously scanned a couple of my slides with a
    Coolscan 5000. They should be back to me in the next few days, and
    I'm looking forward to the results, and comparing to my efforts with
    the 5400. If the quality and depth of focus look good, I might take
    the plunge. One nagging concern is the large quantity of Kodachrome
    in my collection, and how the Coolscan would handle them. Perhaps
    different horses for different courses?
     
  2. jtk

    jtk

    Mendel, you're doing the Lord's work :)

    My own current concern is more with film strips than with slides...and I've noticed that the Plastimounts used by my local pro lab do hold chromes flatter than Pakon and Kodak cardboard used to hold it.

    I think the ideal negative carrier for a Minolta would have polished chrome rails on the bottom, per a camera's film gate, and strips like rubber O-ring on the topside: with the top pressed down and latched, the rubber would stretch the film flat.

    My Nikon, has a motorized film transport/pressure mechanism, doesn't use a negative carrier...requires a different design concept: maybe a large relay pressuring rubber strips that would tension each individual frame to flatness, while it's scanned...

    Minolta could easily be retrofit (by a machinist) with a better-executed version of its basic design...Nikon starts out a little ahead, but would need a powered solution to accomplish really flat film...
     
  3. I think I read in one review the coolscan 8000 has a tensioning device for one it's (medium format?) holders.

    The Minolta holders are sturdy enough (well, apart from the damn latches), and "true" enough, I think. As you say, it's the holder's (whoever's) inability to deal with film curvature, coupled with tight depth of focus, that is causing focus problems.

    Hey, I've posted a couple of full scans with these mounts. Just look for folder with the slide name. Not sharpened, uncropped. Color balance not that hot either, just quick converted 16 bit linear file from Minolta Scan Utility.

    You know what's funny: your stoned troop of slide assemblers keeps coming up in dinner conversation here...
     
  4. Which do you like better - Wess AHX500K or Gepe 7012?
     
  5. Hi Robert, the Wess AHX500K mounts are giving me a higher percentage of the image in-focus. The Gepe 7012, even with my elaborate shimming tricks, were not as good in that regard.

    With the Wess, it's a bit more difficult to adjust the image relative to the mask edge. You can only play with the orientation within the mount. OTOH, the mask dimensions are slightly greater than the Gepe 7012's. wess/gepe:

    35.9/35.8 x 24.4/24.0

    (measured with my new toy: a digital caliper)

    Plus, the Gepe metal masks cast reflections along the long edges, reducing the usable area. I get no such reflections with the Wess.

    But the extent of in-focus with the Wess is only slightly ahead of the Gepe, and still no where near perfect. You really have to be on your toes, carefully manually focussing. And since the traditional dome topography kind of goes out the window with the Wess Mounts, the ideal compromise position is not readily obvious. I keep a log, note the scans with less than "satisfactory" focus, rescan, compare.

    I'm still experimenting. The one roll I scanned so far (and holding) with the emulsion facing the pins on the Wess mounts. Just now with a problematic scan, I remounted with the back facing the pins. Still scanning with emulsion facing the Elite 5400's lens, though. Careful review indicates better overall sharpness, and a greater in-focus area.

    Still, this is very frustrating. I've basically decided to open the purse strings, considering the alternatives, well, anything up to a Coolscan 9000. I do not want to get into wet mounting though, if I can possibly avoid.

    You've heard of the 7 steps in dealing with impending death. I feel like I'm going thru similar steps, coming to terms that there just might not be any prosumer level scanner out there capable of corner-to-corner focus.

    Please remind me what scanner it you are using. Also, any ideas regarding scanner choices would be appreciated. I have a lot of Kodachrome to scan, just to complicate the choice.
     
  6. Just an update. It's looking more and like half the focus problem with the Elite 5400 first gen. is due to the heat of the light source. You do your level best to focus, but the slide warms and bows during the scan. And this is where the Wess mounts has a real advantage. Having initially tensioned the film, this bowing is no longer happening, or alteast reduce near to nil. Getting very high percentage of scans with corner to corner focus.
     
  7. Another update, just took delivery of a direct order from the manufacturer. Made contact through the www.wessmounts.net site I mentioned at the top of this thread. No problems, they were willing ship even a single box (of 50). I settled on a 5 box order, which was a price break point. Arrived about 2 weeks after I placed my order.
     

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