Gaining extra contrast.

[Craig75]

Durst m700 with colour head that has 100 units (not the later ones with 130 or 170 units)

Attached to that a mamiya enlahead for 16mm film. It has a condensor negative carrier and lens as one unit and screws in place of normal enlarger lens

So diffusion into condensor basically.

Printed a step wedge at different filtrations to see what grades this set up can print at and it maxed out at a very hard 2 very soft 3. As im doing 16mm at 8x10 i need as much contrast as i can wring out of enlarger as im losing it with small.neg and size of enlargement.

I'd like to mess around at grade 4 so how do i get more contrast

Paper developer is champion's film and paper developer. Paper is ilford rc multigrade.

Developing for longer ie from my normal 2 to 5 mins has made no difference to contrast.

Ilford multigrade filter pack at grade 5 gives me same hard 2 soft 3 as colour head.

All i can think is to change bulb but i think its only a year old and still giving me same contrast range as when i got it.

Or to change paper developer to something more contrasty but i dont know what.

Or to just use hard grade foma paper.

Thanks for any ideas. Craig

 

[bdial]

Something seems amiss if you can only get a grade 2 or 3 result with the Ilford filter. Do you get a similar result if you mount a standard lens?
Also, the developer and paper are fresh?

 

[Craig75]

I will run test again with a standard 50mm lens and 100m (max on colour head) and grade 5 ilford.

Yup fresh chemicals.

From memory i could get grade 3.5 from that set up but i will do it again. I wouldnt expect to get grade 5 on a diffusion even with ilford filter but im def losing contrast somewhere.

Bit more info - i only have 6x6 mixing box but id have thought that would only slow printing times not affect contrast.

Oh and a bit more info. No filtration at all gives me grade 0

 

[Svenedin]

I'm a bit puzzled that you seem to be dialling in filtration on the head AND using an Ilford multigrade filter. I thought this was either/or. What happens if the head is set to no filtration and you just use the Ilford filters?

 

[Craig75]

I'm a bit puzzled that you seem to be dialling in filtration on the head AND using an Ilford multigrade filter. I thought this was either/or. What happens if the head is set to no filtration and you just use the Ilford filters?

Apologies my bad explation. I mean if i use either maximum filtration or grade 5 ilford then i get a soft 3 / hard 2

The max filteation on head wont be able to exploit full paper grade as its both being diffused and the older 100 scale rather than later 130 or 170 durst scale but no filtration and using just grade 5 ilford is getting me nowhere close either

 

[MattKing]

Sounds to me like there is a whole bunch of flare in your system - most likely between the negative holder and the lens.
How clear does the lens appear to be? It could be a problem with fungus.

 

[Craig75]

Sounds to me like there is a whole bunch of flare in your system - most likely between the negative holder and the lens.
How clear does the lens appear to be? It could be a problem with fungus.

I have horrible thought that could be a big contributor.

the mixing box is 6X6, the enlarger negative carrier is glassless 6X9 , and then all of that is going to whats basically a tiny condensor enlager with a neg carrier mask thats 10x14 so the light path is wide until it enters the enlahead so its coming to wide and strong into 6x9 carrier and bouncing around and spilling out of sides maybe...using a 35mm mixing box would help?

the only negative carriers I have are the holder which is 6x9, 6x9 glass and a 16mm mask (which doesnt quite align with the mask in enlahead so i cant use it in this circumstance.) Would a 35mm mask help?

The seal between enlarger and enlahead is tight and negative is maybe 10x12mm in a glassless 10x14mm mask

Its just a hassle trying to find parts so I have been using whatever I have but I think you are right Matt, its flare and light spill which is going to take time and money to find parts.

Could I change paper developer or do something to curve to compensate for enlarger issue as an alternative. I'd just be curious what difference the two different solutions do to final print

 

[M Carter]

Lith printing can give you an amazing contrast range, but only with lith-able paper - less exposure = more contrast. But if you indeed have flare issues, I'm guessing even lith won't do it.

 

[Mr Bill]

Why don't you try contact printing the step wedge directly to the paper and see if the contrast comes back?

Also, if the enlarger's light source is somehow in question, you could probably do the same contact print using room lights, preferably with an incandescent bulb (exposure time is not very critical as the step wedge can accommodate a really wide range). Be sure to lay the contrast filter on top of the glass/step wedge/paper package.

 

[Craig75]

Why don't you try contact printing the step wedge directly to the paper and see if the contrast comes back?

Also, if the enlarger's light source is somehow in question, you could probably do the same contact print using room lights, preferably with an incandescent bulb (exposure time is not very critical as the step wedge can accommodate a really wide range). Be sure to lay the contrast filter on top of the glass/step wedge/paper package.

The stepwedge was contact printed using enlarger

Yes thats the sensible very first step. Test the filter first with room light is first place to start then seeing where i am and then most likely have to work down enlarger knowing what my maximum potential is. I would never have thought of that. Im feeling better about fighting this head on now.

Thanks everyone. I will report back when i have some progress

 

[MattKing]

I would expect that a 35mm mask and/or a 35mm carrier in place of the 6x9 carrier would help with flare.
By the way, it might help if your thread title was more explanatory. Something like "Printing 16mm film with a Durst M700". That would be more likely to catch the eye of someone with specialized Durst experience.

 

[ced]

Maybe a good cleaning operation of all the glass parts may improve a bit.

 

[bernard_L]

Light leaks from the enlarger: you should see them; if not, they are probably negligible.

1) Did you perform the safelight test?

2) "Printed a step wedge at different filtrations" If, in that test, your wedge is contact-printed onto the paper, you can rule out any lens flare or light leak; you must look for an explanation elsewhere.

3) Buy/borrow/beg different paper and developer.

4) As concerns contrast when actually performing an enlargement, make sure areas outside the image are effectively blocked. "As im doing 16mm at 8x10 (...) Bit more info - i only have 6x6 mixing box" I'm not familiar with that mixing box; does it have an adjustable mask? If not, try to hack a crude mask out of carboard.

 

[Craig75]

Ok .. using masks in negative carrier just basically shone a vignettey box onto condensors - not good. So i removed negative carrier altogether and boxed in that space with aluminium foil and electrical tape so it was light tight. Then went electrical tape mad and sealed off all other very very minor lightleaks.

Cleaned condensor - does look brighter now. I can only clean front element tho as its sealed in to enlahead. Cant really clean enlahead lens as the lens is tiny

Ran fog test and that was clear for 16mins i ran it.

Then my paper + champion developer
100 magenta in colour head : 1.05
Grade 5 ilford filter in enlahead 1.05

New paper from friends box + champion dev.
100m 0.90
Grade 5 ilford 0.75

New paper + ilford multigrade dev from unopened bottle
100m 0.90
Grade 5 0.75

So i had lost half a stop with my paper (and or enlarger) but changing developer had no effect.

My ilford filters are the educational set (the packs without half grades) and were bought a year ago and provably used about 3 times.

Next i will try mrbill's room light test - just need a bulb.

So its either ilford filters or the lamp or me until i run mrbills test

 

[Craig75]

Light leaks from the enlarger: you should see them; if not, they are probably negligible.

1) Did you perform the safelight test?

2) "Printed a step wedge at different filtrations" If, in that test, your wedge is contact-printed onto the paper, you can rule out any lens flare or light leak; you must look for an explanation elsewhere.

3) Buy/borrow/beg different paper and developer.

4) As concerns contrast when actually performing an enlargement, make sure areas outside the image are effectively blocked. "As im doing 16mm at 8x10 (...) Bit more info - i only have 6x6 mixing box" I'm not familiar with that mixing box; does it have an adjustable mask? If not, try to hack a crude mask out of carboard.

Hi bernard.

1. Ran
2. Yes that makes sense
3. Tried new ilford rc paper and developer
4. The light is bounced down into a 6x6 mixing box. The enlarger can take a 6x9 a 6x6 and a 35mm mixing box. I masked the 6x6 box as i dont have the 35mm but it seemed to make no difference.Normally light leaves mixing box and arrives at negative carrier which has a little easel built into it. That distance is say only 4 or 5 cms. However reaching the enlahead screwed into where lens would be that distance is now a lot further to negative. Maybe 15cm or more. In the end i just made widest light path i could hitting condensors in enlahead as their seemed danger of projecting the mask onto condensors. The negative carrier in enlahead is 10x14mm and i am using a mec 16sb camera which makes a negative with maybe 1mm clearance on two sides.

Many thanks for everyones help here. Its very much appreciated

 

[Craig75]

And final results.

100 m filtration = mid grade 4
Ilford 5 filter = mid grade 4

Ilford grade 4 filter contact printed with wedge and room light = hard 2

I had cut 5 filter up so didnt have enough to contact print it.

Gained another 1/2 stop contact printing onto black card base rather than white easel - hadnt factored in effects of that on long exposures at full aperture.

So filters arent getting full contrast but everyones advice managed to lift the contrast on colourhead by a grade and a half which is huge improvement. I am sure i can find more contrast in developing tray to just allow me to use the colourhead on enlarger all way up to grade 5 from this point.

Thanks everyone