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coops
24-Jan-2009, 08:29
I fired up my Omega enlarger the other day for only the 3rd time ( the one with the color head) because I was really excited about some shots I took the day before, Ilford HP5 dev in Kodak D-76. I scanned a few of the negs and with minimal curves adjustment they looked great, with good detail everywhere. However when I tried to print them on the enlarger using Ilford Rc paper, the shadow areas required only 6 secs to expose at f 11. I am new to this but I expected a longer exposure time with what I thought to be a good negative. I know I could stop down but would I lose sharpness?
I guess a negative that scans well does not neccasarily print well on the Omega?
I could increase the yellow filter?

With a well exposed neg, is there an ideal enlarger exposure time I should be looking at that allows dodging and burning etc?

Perhaps my negs are not as good as I think they are?

Bruce Watson
24-Jan-2009, 09:08
I fired up my Omega enlarger the other day for only the 3rd time ( the one with the color head) because I was really excited about some shots I took the day before, Ilford HP5 dev in Kodak D-76. I scanned a few of the negs and with minimal curves adjustment they looked great, with good detail everywhere. However when I tried to print them on the enlarger using Ilford Rc paper, the shadow areas required only 6 secs to expose at f 11. I am new to this but I expected a longer exposure time with what I thought to be a good negative. I know I could stop down but would I lose sharpness?
I guess a negative that scans well does not neccasarily print well on the Omega?
I could increase the yellow filter?

With a well exposed neg, is there an ideal enlarger exposure time I should be looking at that allows dodging and burning etc?

Perhaps my negs are not as good as I think they are?

If you can print them to your satisfaction on a 2 or 2.5 grade paper, they are fine for your enlarger. If it takes a grade 3 or higher paper you might want to increase film development some. Likewise if it takes a grade 1 paper, you might want to back off film development some.

In general, film optimized for darkroom printing will scan just fine. Film that is optimized for scanning, however, will usually be difficult to print in the darkroom, because said film will have a smaller density range and lower Dmax than film optimized for the darkroom. This will cause you to migrate to more contrasty paper grades.

Ralph Barker
24-Jan-2009, 09:08
Too thin? Yes, maybe, no - your choice. ;)

It's difficult to say without actually seeing the negative, and knowing little things like scene brightness range, exposure, developing, etc., not to mention the degree of enlargement, bulb wattage, and so forth.

An old (Kodak, as I recall) book I recall suggested placing the neg on a printed page and being able to see the print through the highlights (dark areas on the neg), as one way to check overall density. Using a densitometer under controlled circumstances is probably more accurate.

But, if you have good shadow detail and reasonable highlight density with normal contrast scenes, you're probably in the ballpark.

Brian Ellis
24-Jan-2009, 10:15
Too thin? Can't say without seeing the negative. But in general 6 seconds is too short an exposure time for a photograph of a normal scene. If 6 seconds gives you good detail in the shadows then the mid-range and highlights are presumably way too light in the print (i.e. 6 seconds was too short a time for them). With a normal negative you should aim for an exposure time of approximately 30 seconds with the lens aperture set to one or two stops from wide open (the usual optimum for an enlarger lens) so that you'll have time to do any necessary dodging. But it's hard to know what the problem is, or even if there's a problem, without seeing the negative.

Bjorn Nilsson
24-Jan-2009, 10:27
An "ideal" exposure time is long enough for you to have time to dodge/burn, but short enough for you not to get bored. :) In reality, there's no such thing. If there's no dodge/burn needed, one second sounds good to me. ;)
Ilford papers are usually quite sensitive, needing quite short exposures. You don't mention what size you are enlarging to, but if it's to 8x10" or 11x14", you don't do much enlargement so times will be short. When doing smaller enlargements, you can stop down a bit further (f/16 or even f/22) without sacrificing anything. At 2x or 3x there is no way you can see any traces of refraction anyhow, unless you go to extremes like f/45 or smaller. While most lenses work the best when stopped down to the middle of the scale, you should be able to use the full scale if you really have to.

Now, as you are satisfied with shadow detail (as the scans show "details everywhere"), you are not under-exposing. It's possible that your developing times are a bit short, but if the prints look alright around grade 2, everything is good. Else you have to adjust the dev.time accordingly.

It does sound like you're close, so don't worry.

//Björn

Andrew O'Neill
24-Jan-2009, 12:24
Try doing a "minimum time for maximum black test" on with a contrast setting on your enlarger that would give a grade 2 on the paper that you are using. Hopefully, you have done a test to determine which settings give which contrast (invest in a 21 step wedge from either Kodak or Stoffer). Anyways, if you know the settings then stick the negative in question in the enlarger and make sure a clear edge of the negative is projected onto the paper. Make a test strip. Ignore the image once you've fixed it, and look at the clear edge that is black. For example, if you did a test strip at 3, 6, 9, 12 seconds, and 9 is black, do another test strip at 7, 8, 9 seconds. Maybe 8 is minimum time for maximum black...or maybe 9. The point is, anything beyond 9 is too long. Now print the negative at the time you determined to give you max black at min time. This test will tell you if your negatives are under/overexposed.

I used to use D-76 and it is a nice developer with HP5+, but I find it MUCH better diluted to 1+1. Slightly better tonalities and sharper grain...and more economical. EI of 250.

Good luck!

Oren Grad
24-Jan-2009, 13:18
It's not possible to interpret your printing time without knowing how big an enlargement you're making and what paper you're using. The three different Ilford variable contrast RC papers - Deluxe, Warmtone, and Cooltone - have quite different printing speeds. The Warmtone, in particular, is much slower than the others.

Anyway, if you can make a print with a full, rich tonal scale using a middling contrast grade, then your exposure and development are OK. So that's the first thing to work on.

If your prints look good but the exposure times are too short to be convenient, you can add neutral density with your enlarger head.

neil poulsen
24-Jan-2009, 14:49
What sized print were you trying to make? 8x10? Smaller?

Louie Powell
24-Jan-2009, 14:57
However when I tried to print them on the enlarger using Ilford Rc paper, the shadow areas required only 6 secs to expose at f 11. I am new to this but I expected a longer exposure time with what I thought to be a good negative. I know I could stop down but would I lose sharpness?



So - that may be perfectly normal. What size negatives? What size print? What light source? I assume that you were not using a contrast filter with the VC paper - that makes everything faster.

Stopping down actually makes everything sharper - until you get to about one stop wider than the smallest aperture when diffraction starts to take over.

Andrew O'Neill
24-Jan-2009, 17:01
Stopping down actually makes everything sharper - until you get to about one stop wider than the smallest aperture when diffraction starts to take over.

I've tested lots of enlarging lenses and f/11 was almost always the sharpest apeture. I wouldn't go beyond f/16 if you are concerned about sharpness, IMO.

If you work out that your negative is "normal", and since you have a colour head, why don't you dial in a bit of magenta? Wouldn't that act as ND and force you to increase your exposure time?

mandoman7
24-Jan-2009, 20:18
You can't really go by the time it takes to expose a certain paper. Different films will have different film base+fog, and other things, like you're bulb's age, or even voltage shifts.
As O'Neill up there suggests, you need to do a maximum black test to set a standard. Then a proof of that negative will tell you a great deal about iso and development.
JY

coops
24-Jan-2009, 21:52
Thanks for all the responses. I will do a maximum black test and go from there

Mick Fagan
24-Jan-2009, 23:28
As you are using an enlarger with a colour head, you may if you wish, add neutral density (ND) by adding all three colours at once.

Basically by adding 30 units of Cyan, Magenta and Yellow, you will be adding one stop of ND. By doing this you will effectively be using, or requiring, one more stop of exposure.

Quite a few commercial enlargers have an ND filter built in, so do some models of amateur enlargers. Having a ND filter built in however, isn't the norm, but emulating one is very simple.

Mick.