wes_sechler

I've dabbled a little bit in Van Dyke prints and can offer you a bit

of help with your problem. The chemicals used to Van Dyke prints are

not sensitive, I believe, to visible light which is why the paper can

be coated under tungsten (indoor) light. Van Dyke paper is, however,

sensitive to ultraviolet light. Generally, Van Dyke prints are made

by contact printing a black and white negative in sunlight. Of

course, the larger the negative the better.

I can certainly relate to the frustrations of temperature and

development times-- temperatures outside the ranges provided in

Kodak's table for development in XTOL. But because temperature vs.

development appears to be a logarithmic function, I did a little math

and statisitics to solve my problems.

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I did so by first finding the logarithm of the development times

provided by Kodak (Pub. J-107), thereby making temperature (Celsius)

vs. logTime a linear relationship. Then I did a linear regression

analysis to determine the equation of the line. And while the

coorelation coeffecient (R^2) is not as strong as one might like (r^2

for HP5+, EI800 in XTOL 1:3=0.99787), the whole concept has worked

well thus far.

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As an example, the equation for HP5+, EI800 in 1:3 XTOL is: logTime=

(-0.04485)(Temp C)+ 2.25152. Simply insert the developer temp

(Celsius) and solve; remembering to take the antilog of the answer.

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Alternatively, one might alson consider visiting the Ilford website

(http://www.ilford.com/html/us_english/bw_chart.html#tempconv) and

downloading their temperature conversion graph.

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Finally, I should add a few disclaimers: (1) I am an amateur, so my

present goal is good composition, (2) I also do mostly medium format

so grain is less of an issue, (3) I've applied this method to XTOL

only, and (4) the most extreme temperatures I've developed at are 61F

and 87F.

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Should all of this be clear as mud, email me and I'll try to expound

I've exposed test rolls of Plus-X in both of the previously mentioned No. 2 Brownies and pull processed one stop-- E.I. 64. The older camera yielded much better results than the other; which would probably have well tolerated full development. Undoubtedly, more test rolls required.

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But this gives rise to the question of ASA (now ISO) ratings for the era in which these cameras were manufactured. Was 125 rated film available during the late 1910s and '20s? Or was ASA 50-64 more in line with the technology/chemistry of the day?

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Many thanks again!

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Wes

I recently picked up of couple of Brownies at a flea market-- a basic, earlier black one and an aluminum Model F.

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The black Brownie, in great shape albeit dusty, still contained a film spool in it which read "Brownie Film" on the flange. Is my understanding, from the film history section, correct that in 1913 Kodak stopped marking film as such? Could I be resurrecting a camera that hasn't been used for 80+ years?

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Secondly, the aluminum bodied Model F is tan in color. I've seen a lot of the colored Brownies constructed of cardboard-like material, but not of metal. Was the Model F also sold in the variety of colors?

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Many thanks!

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Wes

Just thought I'd throw my 2 cents worth in on re-spooling 620 film.

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I've acquired a Foldex-20 camera that will accept both 120 and 620 spools and thus greatly simplifies the process. First I roll the film on to an empty 120 spool and tape the trailing end of the film to the paper backing (in the darkroom) as the end is neared. Then re-roll the film on to the 620 spool. Once complete, I go back to the darkroom to remove the film just in case it is not wound tight enough on the spool to prevent edge fogging.

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While I admit having only spied a few Foldex-20 at antique shops or flea markets, they can usually be picked for between 5 and 10 dollars-- a worthy investement.

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John (?) Craig sells a very wide assortment of instruction manuals for all types of cameras: www.craigcamera.com

On occassion, I've encountered similar, puzzling markings on both Tri-X and Plus-X. The folks at the local camera and photography shop have suggested over-agitation during development as the possible culprit. Since then I have been a bit more conscientious about agitating, thus appearing to have corrected the problem.

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Is there really a coorelation between over-agitation and streaking around the sprocket holes? Perhaps someone more learned can say.