cats lab

Hi,

you should try UV tubes for circuit board making you'll find in any good electronic components shop.

I used that and worked nice.

I built a light box with foam on the back of the cover to press the presensitized board on the film, and worked also for the coated paper for cyanotypes.

You can buy tubes and ballasts or buy an already done uv box. It's up to you.

I used 4 tubes about 3 inches from the glass and spaced about 2 1/2 inches from each other.

The only draw back of my box is that I should have done a cover cut in half to be able to lift the paper without taking any chances to move it, but I already had done the box for my electronics stuff.

I'll redo another that I will be able to use for both photography and electronics.

I might be tempted to hack an enlarger with hi power uv leds one of those days, just to try to see if it can work.

Be careful with the uv lights it's no good for your eyes if you look at them directly.

Cheers,

Cedric

Hi,

I think I took this formula out of another post a few months ago

Water 350 ml

Metol 5 g

Sodium Sulphite 45 g

Diethylene glycol 12.5 ml

Triethanolamine 15 ml

Chlorhydroquinone 25 g

Water to make 500 ml

This is a stock solution

1 part stock + 15 parts 10% sodium sulphite solution

Thanks Dave and Antonio for the answers.

Yes the camera looks pretty old but it in real good shape.

The mechanics are moving flawlessly, it's Linhof after all !

Antonio, I took a look under the ground glass but found nothing.

I searched also under the revolving back but there's nothing.

I'll try to play with 1mm matte blak cardboard and tape a 4x5 film on it to test the camera.

I promised my grand uncle to shot a picture of my daughter with it and send it to him.

Yes, the 270mm seems to be a big long for this camera but I've got spare lens boards so I'll try to attach a 135 or so.

If I succed in taking a picture with this, I'll post it around !

Thansk for all

Cedric

Hello all,

my great uncle gave me today a Linhof camera.

It's not a 4x5, not a 5x7, but looks like a 4"x6".

The holders are made for glass plates and looks like this camera was intended to

shoot postcards.

He never used it. He's got other linhof cameras and we checked many back he's

got but none fits apart the ones he had with the camera.

I'd like to shoot a few sheets of films as he asked me to do.

I had a look on the web, but I can not find any info on this camera.

It has a lens plate with tecnika engraved on it so I assume this might be a

technika but which model ?

The compur shutter is firing right and even slow speeds seem to be more or less

accurate as we checked it on his bench.

I took a few pictures of the camera and the back I have.

http://www.catslab.com/linhof/

Thanks a lot.

Hello all

I acquired a Polaroid HR 6000 Digital Palette at bargain price.

I'll use it mostly to shoot BW films.

My problem is that there were no driver / printing software with it.

Just free polaroid softs but nothing usable.

Apparently I should use Rasterplus 95 or Superprint V5.

I had a look at prices for those softs but they are very expensive so

I was wondering if anyone could help me finding software at affordable

price, like "second hand" software....

For the ones who got this palette, what kind of software are you using ?

Thanks a lot.

Merry Christmas.

I also read that it was T grains but on foma's site they do talk about cubic grains...<br>

Anyway, I bought a bunch of rolls and made some tests using D76 1:1 at 125ml stock per roll in a jobo CPE-2 with lift.<br>

All where processed the same way with freshly mixed chemicals.<br>

dev + 30 secs water stop bath + 3 mins ilford rapid fixer.<br>

It's said not to use acid stop bath...<br>

For now I shot 3 rolls. <br>

On each roll black point, wite point and zones II to VIII + unexposed frame + 2 "regular" pictures, mostly my baby daughter.<br><br>

The surface shot, was a 18% grey chart evenly lighted with fluorescent daylight photo tubes.<br>

The cam is a bronica SQ-Am and the lightmeter a pentax spotmeter 5.<br>

I checked the densities with a macbeth TD932 densitometer.<br>

The base+fog is always measured at 0.24.

<table summary="" border="1">

<tr>

<td>Dev time </td>

<td>Black Point </td>

<td>Zone II </td>

<td>Zone III </td>

<td>Zone IV </td>

<td>Zone V </td>

<td>Zone VI </td>

<td>Zone VII </td>

<td>Zone VIII </td>

<td>White point </td>

</tr>

<tr>

<td>6min30 </td>

<td>0.03 </td>

<td>0.03 </td>

<td>0.09 </td>

<td>0.16 </td>

<td>0.25 </td>

<td>0.37 </td>

<td>0.56 </td>

<td>0.79 </td>

<td>0.91 </td>

</tr>

<tr>

<td>8min15 * </td>

<td>0.05 </td>

<td>0.11 </td>

<td>0.13 </td>

<td>0.25 </td>

<td>0.40 </td>

<td>0.55 </td>

<td>0.80 </td>

<td>0.95 </td>

<td>1.10 </td>

</tr>

<tr>

<td>9min15 </td>

<td>0.04 </td>

<td>0.11 </td>

<td>0.11 </td>

<td>0.25 </td>

<td>0.35 </td>

<td>0.50 </td>

<td>0.65 </td>

<td>0.82 </td>

<td>1.05 </td>

</tr>

</table>

* prewet 2 mins<br><br>

I wanted to check the effect of prewetting the film. It really affects the dev time of this film.<br>

<br>

Also the densities are a bit low compared to some readings done on Tmax, it looks like the 8min15 is near ok. Not too punchy, not too soft for printing on my LPL dichroic enlarger.<br><br>

Grain is not really noticeable on 6x9 and this films really looks like to me like a TMY.<br>

I find the base to be a bit thin and the dye has a really light blue color.<br><br>

I think I'll try this film in ultrafin plus. It's not a very popular developer but I like it a lot.<br>

I'm used to it with TMAX and other films. So I'll can compare.<br><br>

I did all those tests very quickly last sunday afternoon and I'd be happy to share with others.<br><br>

Cedric.

Hi Craig,

I used my jobo cpe2 + lift mainly for B&W processing but one day a lab scratched my dias and did not want to recognize their error.

Since that day, I process all my E-6 and C-41 at home with the jobo.

I mainly use tetenal chemistry and I'm very pleased with it.

The only thing that seems to be critical with E-6 is the first dev temperature. When I process 120 rolls or 4x5" I let the chemistry about 1 hours in the water bath in order to have them at the good temperature. I have a thermometer to check the FD and another for the water bath.

If you follow the tetenal times and temps, this should be no problem.

I usually process 3 films at a time and I prepare only 500 ml of chemistry for 6 films. Concentrates last longer than ready to use solutions. ( if i remember well, the first dev last 2 weeks when mixed )

For C-41 process, it remains the same. I find those tetenal products very fine and even if some may tell that it costs more than having the processed in a lab, I do not care, my negs are like I want them to be !

HI, most led safelights use amber leds @ 590nm wavelength.

If you check the paper specs you'll see that B&W papers aren't sensitive to this light. Spectral sensitivity curves of coulour papers show the same. They tend to be less sensitive around 590 nm.

The main advantage of leds is that they are calibrated to emit light on a single wavelength ( +/- a few percent ). I built one safelight driven by an H-bridge PWM to dimm the output power. I made columns of 5 leds and one 100 ohms resistor in serial X 8 raws. With 40 leds I have enough light for my little lab. I used Agilent high output amber leds 30° diffusion angle. I put a pot to select from 10 to 100 % power output and work fine with any kind of paper. I tested it by putting pieces of paper for 5 minutes in the lab and develloped them. No fogging !

I don't hate signing my work. It's just marking what I'm proud of. I usually just put my initials at the bottom on the right like I do on my paintings. It's just a mark to tell I did the work but not too big enough to be distracting. On the back I put the date , my name, somtimes my sign and sometimes a number if the picture has been printed more than once. BUT... when I put something on the web, I put a scanned sign in one cormer. It might be a bit ugly but I won't let go my shots on the web without it.

Having a sign embossed in the paper sounds nice. I'll think about it !

As Henry said, the coulour dev is the most critical part of the process.

If you use tetenal chemicals , you could ask jobo.

IMHO you'll have to make your own tests.

Depending on which quality you want and how many slides you have to be scanned, price range is really large.

I tested here in France. In 2800 dpi , raw scan, costs round $2/shot, >4000 dpi is $3.

The scans were pretty good, no dust. They well treated my slides.

I had only a few too scan. May be if you got hundreds it could be more valuable for you to buy a film scanner and resell it once your work is done.

I tested epson 3200 flatbed scanner. It's fine for it's price but you'll have hours of work to remove dust.

Have a look at jobousa.com. They make CPA and CPE processors suitable for BW, C41 E6 and all.

It's rotating drum with water bath.

I use it for both films, plan films and coulour paper.

It works fine and give really good results. You just need to be precise on time and temperature.

It won't give the same results as the ones you can get from a pro lab but it's better than what you can get from a street corner lab.