HT-2 Hypo Estimator Query

I recently bought a bottle of HT-2 Hypo Estimator, and my initial results have been puzzling. I have always washed for what I thought was an excessive length of time, and my motivation for introducing this test step was hopefully to cut down on water wastage.

I am using the estimator chart that came with the solution, and it says I should be matching the spot colour to the estimator. The thing is, I'm getting a pinky hue in places that are close(ish) to patch 2 in colour, but the density can vary from one spot to another, and seemingly with the amount of solution I use having a direct effect. I understand that the paper could be clearer from one spot to another, but quite often the results are massively different.

The guide also seems slightly contradictory, or at least unclear. For black and white processed paper 'the spot should have very little or no discolouration; that is, less than on patch one', and for Photographic Print Washing 'a stain that matches patch 2' is ok for all but 'longterm storage'.

I am wondering what long term storage refers to in this instance (5 years, fifty years?) and whether a black and white fibre based print falls under the black and white processed paper, or photographic print washing category?

I am also after some advice on reading the results, as a simple comparison to the estimator seems a little subjective - to me at least.

As I said before, the quantity of solution effects the colour, and the time it is left on seems also to have a real effect. It seems I would have to wash forever to get a completely clear patch?!

What sort of life expectancy might I expect from each patch, and what might a worst case deterioration look like if the spot matches patch 3. I have some untested prints that look good after 3 years... should I be concerned?

This is a bit long winded and imprecise, but any observations or suggestions ( and hopefully reasurance )would be much appreciated.

Thanks,
Ciaran

Solarize said:

I recently bought a bottle of HT-2 Hypo Estimator,
and my initial results have been puzzling.

Click to expand...

I wouldn't worry about the "processed" vs "washing".
A little redundant on their part.

First of all the HT-2 test does not indicate at archival
levels. BUT no stain does mean very close to archival.

The test is done drop wise. The silver within combines
with any sulfur present in the emulsion. The stain is silver
sulfide. The drop stays in place 3 minutes then is blotted
off. The color must be read within a very few minutes
of turning the lights up. The sulfide is light sensitive.

Any further questions? Dan

dancqu said:

I wouldn't worry about the "processed" vs "washing".
A little redundant on their part.

First of all the HT-2 test does not indicate at archival
levels. BUT no stain does mean very close to archival.

The test is done drop wise. The silver within combines
with any sulfur present in the emulsion. The stain is silver
sulfide. The drop stays in place 3 minutes then is blotted
off. The color must be read within a very few minutes
of turning the lights up. The sulfide is light sensitive.

Any further questions? Dan

Click to expand...

Light sensitive.... I am a dope

There I was applying and checking it beside the window. Ok, so I fix and wash the print, and should I let it dry before testing? I had been experimenting on a dry print, and on the borders and image area. The stain intensified over time, confusing me further. Are subdued red light conditions ok for applying the drop?

Thanks Dan.

Solarize said:

Light sensitive ...

Ok, so I fix and wash the print, and should I let it dry
before testing? I had been experimenting on a dry print,
and on the borders and image area. The stain intensified
over time, confusing me further. Are subdued red light
conditions ok for applying the drop? Thanks Dan.

Click to expand...

One correction. The test solution contains silver nitrate.
It is that which is light sensitive. The silver sulfide may
or may not be light sensitive. Any body know?

I test dry paper. Damp paper will allow bleeding
of the drop causing dilution. Play with it some. IIRC
I've used more than one drop, even stirred it some
with a toothpick.

I've a night light on, not to close by, when I apply. A dim
white will be OK. Shadow while the drops soak in. I usually
apply a few drops at half minute intervals then blot off
in succession.

How you use your fixer and your methods of washing will
affect the thoroughness of the cleaning over the
sheet as a whole.

The HT-2 test is considered a valuable at home method
of insuring clean prints at very near archival levels; no
stain. Once a methodology is established, infrequent
testing should do.

I've some testing myself to do. I'll use multiple sheets,
perhaps four, unexposed; through developer, fix and
hold. Wash, drying, and testing follow. Dan

The HT-2 test area will brown up with time. None of my fixer test prints have clear border areas now due to that very fact. The browning varies from just detectable to intense depending on the amount of wash carried out.

PE

Ciaran,

I used a desk lamp with a 15W bulb pointed at the white wall of my darkroom when I performed tests with HT-2 recently.

Tom.

Photo Engineer said:

The HT-2 test area will brown up with time. PE

Click to expand...

True, areas initially clear will slowly brown.
I've tested Ilford's version of the HT-2 against
Kodak's version. The results, Ilford's spot tests
are sooner to brown and as time goes by they
turn a darker brown than those of Kodak's.

Ilford's is without the acidic acid; no more
than a 1% solution of silver nitrate. Dan

Thanks everyone. This has cleared everything up and is a real releif. I am washing the prints enough.... phew!

Ciaran

Silver nitrate is not light sensitive until it comes in contact with an organic substance or is converted to another silver salt through chemical reaction. Wet plate photographers often "Sun" their silver nitrate to clear it of undesirable salts.

dancqu said:

True, areas initially clear will slowly brown.
I've tested Ilford's version of the HT-2 against
Kodak's version. The results, Ilford's spot tests
are sooner to brown and as time goes by they
turn a darker brown than those of Kodak's.

Ilford's is without the acidic acid; no more
than a 1% solution of silver nitrate. Dan

Click to expand...

Dancqu, can you say more about the Ilford test? Is it a published formula like Kodak's HT-2 or is it a packaged product? If it is a formula, could you post the formula here?

Thanks!

CBG said:

Dancqu, can you say more about the Ilford test?
Is it a published formula like Kodak's HT-2 or is
it a packaged product? If it is a formula, could
you post the formula here? Thanks!

Click to expand...

From the; Ilford Manual of Photography, 5th Edition,
1958. Formula; 1% solution of silver nitrate.

I allow the staggered drops three minutes then blot.
Examine immediately after. Or, the paper may be
washed. With excess silver nitrate removed the
spots will not darken. Dan

That's a pretty simple formula.

Thanks!

I'm not sure how plain Silver Nitrate vs Silver Nitrate in Acetic Acid are any better or worse. The latter is used in most cases and has been in use for over 100 years.

PE

Another Query about HT-2 Hypo Test

Hi all,

I revive this old thread because I am back to FB printing, and tried to use again an HT-2 test bottle I made two years ago. From memory, I followed the Unblinkingeye website formula.

Of course, this HT-2 tester was stored in a full, well stopped, brown glass bottle, in obscurity, but I was concerned by the shelf life of this product.
I found (there was a url link here which no longer exists), and I agreed the better way is to test it, with a very quickly washed FB test print.

Reading, in the excellent "Way Beyond Monochrome" book, that the test should be made in subdued light, I interpreted it (maybe mistakenly), that it can be conducted in red, safe darkroom light...

So I was a little puzzled, when, for the five spot of HT2 tester I placed on the quickly washed sheet (Forte Fortezo Museum paper...), after 5 minutes, absolutely no one let any stains at all !

So, my question : Is "actinic" non-red light is mandatory when HT2 testing ? If yes, how the ambiant available light affect the test result ?

In advance, thanks you,

Best regards,

Raphael

The stain cannot be seen under red light. It must be viewed under dim white light to be visible.

I have found that it can last for years as long as the solution itself does not turn brown.

PE

Photo Engineer said:

The stain cannot be seen under red light. It must be viewed under dim white light to be visible.

I have found that it can last for years as long as the solution itself does not turn brown.

PE

Click to expand...

Thats good news

I have some 2 year old HT2 and was wondering if I should replace it

Thanks

Martin

Photo Engineer said:

The stain cannot be seen under red light. It must be viewed under dim white light to be visible.

I have found that it can last for years as long as the solution itself does not turn brown.

PE

Click to expand...

Many Thanks, PE, it's good to know about the keeping properties. Especially if one knows the current price of Silver Nitrate.

However, probably I have a slow brain, but I persist to be confused why I didn't see coloured spots of the test sheet I made : I didn't see them, even when putting the sheet in white light !

So, the question I ask : is actinic white light (even faint) is mandatory, during the two minutes after put one drop of HT2 ? If not, it's means that my HT2 bottle is probably gone bad.

Another remark : in "Way beyond monochrome book", they say HT2 should be conducted on a damp print, and the HT2 Kodak note (J11-1985) stats that the print should be dry ! Who is right ?

Again in Way beyond book, it is said that the test can be "fixed" for posterior reference with salted water. How does it work ? I processed this way with my test sheet, before switching the white light on, does it explain why I got no stains ?

Many thanks in advance,

Best,

Raphael

Raphael;

Ok, this is Silver Nitrate in Acetic acid. It tests for retained hypo. It forms a brownish red stain in the presence of hypo and Silver complexes which cannot be seen in red light. The Kodak instructions that I have are not specific to wet or dry. They are vague. They are vague also as to the lighting conditions. I have several sets of documents though so I'll look more.

Anyhow, Silver Nitrate in acid and in excess of that needed to react with a halide will form this color, but the color is not fully evident until exposed to ambient white light. If you leave a well washed print out in the light, and with this test solution on it, the tested area on the print will also darken even if clean, so extended white light can give a false positive! The color from the test solution that is valid shows up within the first 5 minutes or less. It is called "printout".

It is akin to what happens if you put a drop of Silver Nitrate on your finger (not recommended) and expose it to light. Your finger turns dark brownish black.

So, one drop on a white area on a print. Expose to light and over 5 mins if you see a dark brown red stain, the wash is insufficient. If it is good, you see no color or a light yellow. If this "good" print is left in the light for a few minutes to several hours it will turn as dark as a "failed" print test.

PE

I understand better...

Hi PE,

Many thanks for your extensive and clear reply !

I understand now better why I hadn't get any stains with my way of testing.

I presume than one of your document is this Kodak .pdf, I used it for reference.

Again, thanks you very much,

Regards,

Raphael

I have a Kodak PDF, a Kodah How To book and the packing stuffer from a box of the chemistry. So I have 3.

PE

Hi all, hi PE,

So I tested again the quickly washed FB print with the HT2, a few meter from a 60W incandescent wall light. And again, after 5 minutes, I got no stains, or barely visible one !
Then, I done the same test using another FB paper (Adox Vario Classic), with a quickly washed print : I got more visible stains, but I have to go under a brighter light to see them without hesitation. I am confused again :confused:

I presume I had storage problem with the HT2 bottle, but I find it rather strange, as there is no visible alteration on the test solution (clear, transparent color).

Photo Engineer said:

Ok, this is Silver Nitrate in Acetic acid. It tests for retained hypo. It forms a brownish red stain in the presence of hypo and Silver complexes which cannot be seen in red light. The Kodak instructions that I have are not specific to wet or dry. They are vague. They are vague also as to the lighting conditions. I have several sets of documents though so I'll look more.

Click to expand...

I find this vagueness rather surprising considering the subject importance ! Especially after reading the extensive "Washing Film - Best Environmentally Friendly..."thread on the matter.

Best regards,

Raphael

I have now read 3 Kodak versions, test wet, dry and not specified. So, I guess it does not matter. I get a rather dense test when there is retained silver. So, if there is no color and no precipitate in your test solution it should be good. As noted, it is Silver Nitrate in Acetic Acid. That is all. Little there to spoil unless it was exposed to heavy light.

PE

Silver nitrate is somewhat light sensitive in that it will turn gray with prolonged exposure. This is why it is packaged preferably in brown glass bottles. Silver sulfide is not sensitive to light. If it were then sulfide toning of microfilm for archival storage would be valueless.

The Kodak test solution is probably better than the Ilford. The reason for the acidification with acetic acid is to prevent silver oxide from forming with any alkali still present in the paper. In the presence of hydroxyl OH- ions silver hydroxide first forms an then quickly decomposes to silver oxide. Silver oxide is brown or black and its presence would distort the test results.

back with a vengeance

Hi PE,

Photo Engineer said:

I have now read 3 Kodak versions, test wet, dry and not specified. So, I guess it does not matter. I get a rather dense test when there is retained silver. So, if there is no color and no precipitate in your test solution it should be good. As noted, it is Silver Nitrate in Acetic Acid. That is all. Little there to spoil unless it was exposed to heavy light.
PE

Click to expand...

Conducted a few more test, but under broad fluorescent light.

I was then able to see that there is in fact a few small cristals or "sand grains" on the bottom of the bottle. Does it mean that I have to discard it ?

However, with a more generous lighting, I got quickly non-ambiguous stains on the Adox Classic paper I tested. The next stage is to test this way, quickly washed and archival washed print, side to side, to see if there is a significant difference.


Where I am still puzzled, is that I cannot get any significant stains on the Forte Fortezo paper, whatever lighing I use, and even if I let the HT2 drop more than 15 minutes.

So, another question I have, maybe a dumb one, is : if the fact that the Forte Fortezo is stated to be a "chloro-bromide" paper can affect the Hypo Estimator testing ???

Regards,

Raphael

Well, it does sound as if you test solution is going bad. It should be clear of sediment and like water.

As for test results on different papers, well, they fix at different rates and wash at different rates. RC washes far faster than FB paper. So, at this distance, I don't think I have an answer.

Sorry.

PE