Which one is the 'base' side?

[jbrough]

OK, stupid question. I am duplicating slides with Ektachrome 5071 duping film (as no-one here in Auckland still optically copies slides) and the books say 'Place the slides to be copied base side up'. I can't for the life of me figure the 'base' side. Is it the normal (i.e. viewing) way up, or 'upside down'? Any help is much appreciated.

Cheers,

Jonathan

 

[xxloverxx]

I take that as upside down.

 

[payasam]

Base very shiny, emulsion dull.

The procedure you plan to use is not clear. If you'd explain, members can tell you what to do.

 

[drewbarb]

Shiny side is the base; it's the top/front as you normally view processed film. The emulsion side (the more delicate side) has a matte surface and will be away from you as you view the image.

 

[MartinP]

If you are contact printing then emulsion-to-emulsion. If you are projection printing (eg. with an enlarger, from 120 / 35mm to 35mm) then you will want the dupe film emulsion-side up and the source transparency the 'normal' way round, with the film-base to the light-source. The latter is just for orientation consistency with original transparencies when mounting them, projecting etc. Using one of the slide-copier devices, then the film-base would be towards the camera, so the result is the 'right' way round.

 

[payasam]

MartinP, this is the recipe for laterally reversed copies.

 

[jbrough]

Thanks for all the info - I think I have a handle on it now but, to clarify, I am copying slides on an Illumitran copy stand, so the slides are placed on a base with a strobe light source behind. So I have should them the 'normal' way up (as I am doing) - I think?

Cheers,

Jonathan

 

[Dwig]

...So I have should them the 'normal' way up (as I am doing) - I think?...

yes

You want the image to look correct when viewed from the camera's position so on an Illumatron duplicator the base side should be up.

The base side is:

1. Usually the shinny side
2. The side toward you when the image looks correct (not a mirror image)
3. Usually is slightly convex (film tends to curl base side out)
4. The side of a slide mount that has the branding printed on it when properly mounted

The emulson side:

• Usually the duller side
• When viewed with the emulsion side toward you the image is reversed
• With some films, notably Kodachromes, it will show a relief image when viewed at a sharp angle
• Usually is slightly concave (filim tend to curl emulsion side in)
• The side of a slide mount that is left blank and is the dark side on two color plastic mounts, if the slide is mounted properly.

 

[MartinP]

Ooops, as Payasam points out, the projection printing orientation of the 'source' transparency (in the neg-stage) should indeed be the other way up to what I wrote above. Sorry about that 😱 The last time I did that regularly was approximately twenty+ years ago for making 4"x5" inter-negs and I was not properly realising that in, this case, the OP was duping not making a negative.

I suspect I need to post only when I am more awake....

MartinP, this is the recipe for laterally reversed copies.

 

[MartinP]

Ooops, as Payasam points out, the projection printing orientation of the 'source' transparency (in the neg-stage) should indeed be the other way up to what I wrote above. Sorry about that 😱 The last time I did that regularly was approximately twenty+ years ago for making 4"x5" inter-negs and I was not properly realising that in, this case, the OP was duping not making a negative.

I suspect I need to post only when I am more awake....

MartinP, this is the recipe for laterally reversed copies.

Edit: I just read the bit about the Illumitran. Depending on what model and flash you are using I noted that the first flash after a pause for setting up etc. was always stronger than the ones given a shorter recycle time (when making multiple copies), even waiting correctly for the ready-lamp to go on. It seemed that the capacitor slowly charged up a little more even after the lamp went on. The solution was to fire off the 'first' flash using the test button, then continue making the dupes + winding-on just when the lamp went on. This improved the exposure consistency quite a bit. Don't forget the correction filters either; a starting value should be with the dupe film.

 

[Dwig]

... I just read the bit about the Illumitran. Depending on what model and flash you are using I noted that the first flash after a pause for setting up etc. was always stronger than the ones given a shorter recycle time (when making multiple copies), even waiting correctly for the ready-lamp to go on. ...

This is typical of all older style electronic flash systems that use neon ready lights and many of the more modern systems as well. It affects the brightness of a full power manual flash and the range of an automatic flash.

There can often be a photographically significant increase in capacitor charge for up to double the "ready light on" time. That is, if the ready light comes on in 10 seconds, the capacitor will continue to increase in charge for an additional 10 seconds. After that the additional charging as diminished to a photographically trivial amount. You should either follow the "shoot as soon as the ready light comes on" approach or you should always wait at least double the recycle time (the time until the ready light comes on), whichever best fits your workflow.

I managed a camera store years ago which, for a while, used a Beseler duplicator that was very much like the Illumatrons for making internegatives. We used the "double the recycle time" approach. The time required to change to the next slide was usually too long to make the other approach any time saver. There were often only one or two slides in any one customer's job and returning one jobs originals to its package before opening the next package took far more time than a recycle.