reversal developping liquid emulsion (tin/ambrotype)

I wonder what the alternative options are if I want to make an ambro/tintype with the use of liquid emulsion, other than the use of Rockland's reversal developer (or the whole tintype kit). I'm searching on the web for some time now, but find it very hard to find any information how to get a positive with the use of liquid emulsion. The emulsion I can get in my country is Maco/Rollei Black Magic (variable contrast), which seems a very recommended high-standard product. So, let's say that this is the emulsion I want to work with, in combination with a digital transparency/contact print process on black metal or glass, get the final image in positive, while the blacks are transparent, and the lights are semi-to opaque. The final image should have a good overall density, strong blacks, good highlights and good greyscale range. (No strong black/whites without anything in between.) Thanks.

The classic ambrotype or tintype is not a reversal process actually. It's a negative image over a black background, and when viewed with reflected light, the background is darker than the image, which gives a reversal effect. Since highlights are light reflected off the dark silver image, they will never appear as bright as higlights in a print or conventional transparency.
Though the normal collodian emulsions are different, you should be able to get the effect you are looking for by coating on a piece of black painted glass or metal and normal processing.

If I coat black glass or a black metal plate with liquid emulsion, and I expose it, do I get results similair to ambro/tintypes, by just develop it with a normal B&W developer?... Then what's the Rockland tintype kit all about?

The rockland tintype kit is basically their tintype emulsion, some developer, and some black aluminum plates in a box. The tintype emulsion is just a liquid emulsion that is a bit runnier to allow for thinner coatings, and it develops to a nice brown tone, as compared to the fairly neutral black of liquid light, though that also can be made to work.

I'm sorry to say this, but this cannot be correct. The Tintype developer is not just a developer that gives a nice brown tone to liquid emulsion. As far as I understand, this is a reversal developper. What normally is transparent (the lighter parts or the image) is opaque with an Ambro-or Tinype, and the shadows are transparent. This is how it is with an Ambro and Tintype. I own several 19th century examples. The glass plate renders transparent in the darker parts of the image, where the lighter parts are opaque. No matter how they are viewed (as opposite to a daguerreotype) they look always the same. The back of the glass is covered with a small black piece of paper. With a liquid emulsion I would get exactly the opposite; black will be more or less opaque, the lighter parts are transparent. If I would coat a glass with liquid emulsion, and develop it the regular way, and then put a black piece of paper behind it, I would see nothing. I guess..?

Here, this is what I am looking for; http://unblinkingeye.com/Articles/WPC/WPC3/WPP14/wpp14.html

Danny,
If you coat a black plate with liquid emulsion and you expose it using a negative (film or digital), you will get black shadows and black highlights. This would be with regular paper developer. The Rockland kit developer is a reversal developer. Regular paper or film developer will not give you what you want.
I gave up on the Rockland kit due to inconsistencies in outcome. I tried to make my own reversal developers, with frustrating results. A person more adept at chemistry (and with more patience than me) might be able to get good results, however. You can do a search on this site for reversal developers.
I did a few images by taking the black aluminum plates and painting them with a cream colored spraypaint. Then I coated with liquid emulsion and exposed the negatives. Regular paper developer resulted in black (dark) shadows and cream colored highlights. Of course you can make your highlights any tone you want, depending on the color you paint your plates.
This worked pretty darn well, but you will never get the look of a true wet plate unless you do the real thing.
Good luck,
Steve
www.scdowellphoto.com

Steve, thank you for your reply. I've read about the inconsistent results of Rockland's developer, one thing that makes me nervous to be 'depended' on in a creative process. Like you, I was thinking about a cream colored base as an alternative. I did a color sample test on one of my 19th century ambrotypes, and was surprised to see how creamy/warm gray the lightest parts actually where! I found ivory colored opal glass that has my interest as well, perhaps in combination with a toner. The Physautotype has my interest as well. It's pretty obscure. But Physautotype is a whole different ball game than liquid emulsions, with probably lots trails and error. But it is a direct positive process.

Compliments for your work. I love the bokeh in your gum/platinum prints!

Thanks Danny,
Good luck with your trials.
Can you tell me about the physautoype and how they are done? I've heard the term, but I don't know what they are.
Steve
www.scdowellphoto.com

Steve, take a look here; Dead Link Removed and a discussion with some 'experiments' here; (there was a url link here which no longer exists)