The longest Survivor: 120 or 135 format?

[JohnTF]

Interesting in itself - I suspect you get similar effects to wet plate, but with less exposure time needed. You've now educated me! I've never got beyond using a few sheets of paper in a No 3 Kodak, but if the chance ever came along to do it... I believe there are a few people doing Daguerrotypes* as well, but I hope they've found a way to do it without using mercury!

Adrian

*these are really magical to see in the flesh.

Yeah, the mercury is getting hard to find. ;-)

When I cleaned out my class room, I found about ten lbs. It was in the good bottles, glass, covered with plastic, but it all went to recycling along with the dozen lab thermometers.

Did you notice the chemistry of the wet plate process?

Regards, John

 

[Roger Hicks]

Well, my results were consistent with an ISO of 640 to 800. I'd say that is more than +1/3 stop. Personally, I liked the stuff.

HP5 Plus in DD-X -- true ISO 650 to 800.

Cheers,

R.

 

[Skiff]

Skiff: The re-introducing of neopan 400 is news to me, definitely good news,
I checked with Maco, the neopan is not available yet,

But it is available at Maco:
http://www.macodirect.de/fuji-neopan-c-1_6_70_735.html

And also at B&H, Freestyle, MX2, Fotoimpex, Nordfoto, Spürsinn, Silverprint, AG Photographic, Firstcall......

nor japan camera hunter was not aware of it, from where is your info coming of re-introducing neopan 400 ?

It was presented by Fujifilm at Photokina this September.
It has been discussed in some threads here, in the Leica User Forum, at apug and aphog, at flickr "I shoot film" and some other places.

 

[Muggins]

Did you notice the chemistry of the wet plate process?

I didn't, John. The wet plate bit is using collodion (gun cotton - nitrocellulose) in ether to stick your photosensitive compound to the plate, and I think you use a different silver salt and react that with something to produce said photosensitive bit - but Wonkypedia could probably come up with a better answer than me!

Random aside - apparently Victorian prints used albumen from eggs to stick the photosensitive compound (hence albumen prints), creating a huge demand for eggs, and supposedly you could buy cookbooks with recipes for all the left-over yolks in after you'd used the white for coating your papers.

Adrian

 

[JohnTF]

Beyond the ether and gun cotton, the developers seemed to be cyanide, and not K ferrocyanide -- like be careful not to insert a finger with a cut danger.

Storing ether is tough too, as I understand, it forms explosive crystals over time, as if it was not dangerous enough.

Sounds like a list of stuff we paid some people to cart out of the department.

I never looked too closely at the process for creating light sensitive halides-- that's beginning to look like the easy part.

Interesting though.

I still have some interesting papers, probably some good? in the darkroom in the basement-- Including a Czech Silver Iodide contact paper.

Had more plans than ambition?

J

I didn't, John. The wet plate bit is using collodion (gun cotton - nitrocellulose) in ether to stick your photosensitive compound to the plate, and I think you use a different silver salt and react that with something to produce said photosensitive bit - but Wonkypedia could probably come up with a better answer than me!

Random aside - apparently Victorian prints used albumen from eggs to stick the photosensitive compound (hence albumen prints), creating a huge demand for eggs, and supposedly you could buy cookbooks with recipes for all the left-over yolks in after you'd used the white for coating your papers.

Adrian

 

[Rob-F]

HP5 Plus in DD-X -- true ISO 650 to 800.

Cheers,

R.

Okay, and while on that subject, Roger, what do you consider the true ISO of Tri-X in DD-X? Or in Microphen?

 

[Roger Hicks]

Okay, and while on that subject, Roger, what do you consider the true ISO of Tri-X in DD-X? Or in Microphen?

Well, it's not consider: it is testable. But the truth is that I've forgotten (Ilford used to do ISO speed testing on their rivals' films as well as their own, and they told me quite a lot of the numbers). As far as I recall, it was ever so slightly slower than HP5 Plus: not even a third of a stop, which is generally reckoned to be the least that matters. ISO speeds also vary with the age of the film and the degree of agitation (more agitation gives a tiny bit more toe speed for a given contrast).

The difference between DD-X and Microphen was likewise tiny, with Microphen giving a slight edge: about 1/6 stop, maybe.

In other words, the maximum likely range for film of the same age is something like Tri-X in DD-X (the slowest combination), ISO 600-700; HP5 in Microphen (the fastest combination), ISO 700-850. Minimal agitation versus constant might stretch the limits to 500 and 900, but I doubt it.

But as I say, this is recollection. Once I'd satisfied myself that the differences were trivial, I stopped worrying.

Cheers,

R.

 

[Rob-F]

Seems surprising that HP5 (or anything) would push better than Tri-X. But then, this isn't really pushing, is it? It's really bona fide speed increase, a rather different thing. Well, I'll have to include some HP5 in my next film order.

Thanks, Roger.

 

[Roger Hicks]

Seems surprising that HP5 (or anything) would push better than Tri-X. But then, this isn't really pushing, is it? It's really bona fide speed increase, a rather different thing. . .

Exactly. It's a question of toe shape
Cheers,

R.

 

[Photo_Smith]

I don't know if this is the case but I was once told that DDX is essentially a liquid version of Microphen. Those speed increasing developers are better at converting the internal image from each grain that is the interstitial areas where crystal defects occur giving higher efficiency.
They really do increase effective speed and shouldn't be confused with pushing.

 

[Roger Hicks]

I don't know if this is the case but I was once told that DDX is essentially a liquid version of Microphen. Those speed increasing developers are better at converting the internal image from each grain that is the interstitial areas where crystal defects occur giving higher efficiency.
They really do increase effective speed and shouldn't be confused with pushing.

I've been told the same thing by Ilford. The changes are such things as potassium salts for higher solubility (in a concentrate), possibly a different phenidone variant to resist hydrolysis... Minor stuff, but enough to make a tiny difference in film speed. And I mean TINY.

Cheers,

R.

 

[HHPhoto]

Mark and Roger:
AFAIK (and confirmed by the MSDS data sheets) Microphen and DD-X are similar, but not identical.
Microphen is a hydrochinone-phenidone developer and DD-X is a hydrochinone - dimezone s developer.
From my experience:
DD-X delivers significantly finer grain than Microphen.
Microphen gives a little more speed.

Cheers, Jan

 

[jet1944]

I have a kiev88 I am still trying to learn photography but the price of 120 devevoping is high because I like b/w,there was a time when it was the other way round

 

[Spanik]

If it really comes to that you can still coat glass plates yourself.