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Whats with DR5?

Stephen Frizza

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I have heard Fuji Across, Agfa APX and some Foma films can not be processed
via the DR5 process. I am curious why this is? Is it that the results just look unappealing or is there some chemical property preventing the process from working of course I understand if this is trade secret, it just makes me curious.

Ide also like to say that whatever Dr5 process actually is...the results are AMAZING.
I commercially process black and white reversal down here in Australia using the Scala process. The results are good but the dr5 process is something else and well worth trying!!!
 
I am curious as to what use the black and white "slides" can be put to....not questioning dr5 whose excellent reputation obviously stands on its own merits. Simply wondering why people actually use the dr5 process. For instance, why would someone process an 8x10 negative via dr5, i.e., what is the "value" ? Thanks.
 
There is many applications, they are perfect for black and white copy work without tone that can be introduced when copying with E-6 and not having colour temp of light correct etc... They are lovely for projection, they allow for black and white ilfochrome prints. they can be toned and altered for fine art applications, they are very archival...the list goes on.

yep Dr5's qualities are brilliant.
 
I agree with all the benefits mentioned so far, but for me the main benefit is the increased tonal range as compared with 'regular' development of the same film.

As Ian Grant said in another thread, the advantages of b+w reversal are:

1: Long tonal range
2: Very fine grain, and excellent sharpness
3: They Scan or Project well

(there was a url link here which no longer exists)

Cheers,
Gavin
 
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Does anyone actually have any documents of substance to back up the "long tonal range" assertion? Sounds like voodoo to me.
 
In reply to clayne's comment:

Nothing mysterious just simple optics. When you look at a print the light must be reflected into your eye from the substrate. This means that the light must pass through the emulsion twice. This effectively shortens the tonal scale. This problem does not occur with projected media hence the longer tonal scale.
 
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clayne said:
Does anyone actually have any documents of substance to back up the "long tonal range" assertion? Sounds like voodoo to me.
Click to expand...

processing my own scala process film and seeing it in scala chemistry and seeing the exact same images with Dr5 yes i have seen and what is said is true
 

Seriously? Are we really going to ignore the obvious here?

Are you projecting said slides directly into your retina?
 
Transmitted light is brighter than reflected light... that's the reason for the increased tonal scale of transparencies.
 
clayne said:
Seriously? Are we really going to ignore the obvious here?

Are you projecting said slides directly into your retina?
Click to expand...

Please read what I said and not what you think I said. I don't know why this is so difficult to grasp.

Let's look at it this way, take any print and note the contrast. Now illuminate the print from the back. You will see a change in contrast between the two lighting methods. The only difference is in how many times the light passes though the emulsion. Once for transmitted light and twice for reflected light. The light is attenuated twice during reflection.
 
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I don't have much of an issue over the debate of reflected light vs transmissive - however that's an entirely separate thing apart from negative vs positive processing. The assertion being made was that having one's black and white film reversal processed results in an longer tonal scale.

I say that it's unfounded, voodoo, and at best only indirectly related to a final viewing medium - for which one is pretty much tied to direct viewing on the lightbox or all bets are off.
 
For what it's worth, I need reversal processing of 4x5" sheets for an autochrome/screen-plate experiment I'm working on. I'm gonna send a few sheets to dr5 before I try to do it myself.
 
Don't bother buying the service, OK? I loved Scala 6x6 and 6x7 slides--truly jaw-dropping projected and wonderful scanned. Dr5 slides from TMY-2 are equally impressive. Nobody has any intention of forcing you to buy DR5's service, delusional chumps that we are. Why so snarky?
 
I seriously have no issue with DR5. But if people are going to start saying that reversal processing equals results with a longer tonal scale based on hovering over a lightbox then I take issue with that. On top of that we now have "reduced grain" thrown in the mix.
 

There may be two phenomena involved here. One would have to look at equivalent negative and positive images and compare the contrasts with a photometer. But, the assertion that there is an apparently longer contrast range for slides is a true one. It is all it the eyes of the viewer.
 
Gerald is correct. The actual loss, according to reports I have read, are up to 0.6 Log E or 2 stops.

The difference is due to the thickness of the emulsion on paper vs the reflection of the projected image from a beaded screen.

If you uses a high intensity illuminant at right angles to the surface of a reflection print, you see an image similar to a projected slide.

PE
 
To answer the OP, it may be that some films are too soft to go through the DR5 process. All reversal B&W processes involve a harsh bleach step which can harm very soft films. IDK for sure, but this is a thought to consider.

PE
 
In addition to what PE said, it may be that some of these films cannot build up enough density in the reversal process to yield a good result. From what I recall DR5 uses a chemical foggant for the reversal step.
 
Maybe David Wood will come and answer this himself, but my impression is that the process is tweaked for each film type, and for some film types, the results are just unappealing or maybe foggy or not on a suitably clear base, which are just intolerable for a transparency.

I think the original main attraction of DR5 was for magazine photographers who were shooting B&W for editors who liked to work with transparencies. They were easy to edit on the light table and to inspect with a loupe, and they are self-proofing, so they don't require photographic prints, and the printer has a reference to know what the image should look like. That the results are also beautiful is an added benefit.
 

I attended a club meeting when a LF Landscape photographer lectured and brought some of his works. He does stock with LF and gets DR5 to scan the positives. He says the detail is astounding and from what I saw, I believe him.
 
What I was debating is that the detail and/or tonality is only appearing to be greater because the positive form allows direct examination on a transmissive lightbox. There's no reason that negative film lacks the same detail on a lightbox - it's just that it's rather useless in negative form.

To actually view the images in larger than the native film size they still have to be enlarged and projected on to something and the only case in which i can see reflectance not coming into play would be a scanner->monitor combination.

Still won't look as good as the lightbox and I'm definitely hesitant to place much weight onto claims of "enhanced detail", etc. Heard it plenty of times before.
 
Another reason for shooting B&W transparency is the ease of making enlarged negatives for alt-process prints. The longer contrast range of B&W transparencies make them superior to color slides for this use - though you do lose the flexibility of using color filters for image enhancement (enlarging a Kodachrome onto pan film using a red filter for darkening skies, etc.). Projecting the transparencies lets you evaluate the image without having to make proof prints or contact sheets.
 
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