enlarging lens / unsatisfacory prints
The title emplies these are related, not really, just have two separate questions.
First: I see lots of text that says that a normal enlarging lens for 6x7 format should be 90mm. Is there any advantage to using a 100mm or 105mm? Any disadvantages? Fred Picker says that image quality will be sharper by using a lens that is larger than what is considered "normal".
Second: Your prints that are not satisfactory from any given darkroom session, do you hold on to them in a file for all documentation of the session or throw them away? throw some of them away? Basically, how much of unsatisfactory prints, if any, do you hold on to after you have reached the final, acceptable print? Just curious.
For the first question...
the reason a larger than "normal" lens is recommended is that the lens' circle of coverage is larger than the negative, so you will have full, even illumination of the negative and the corresponding print on the baseboard. The downside is that you're putting the negative farther from the baseboard to make the same size print, so you're increasing the exposure time as well.
For reject prints... I keep them around until I've got my good finished print... they serve as a reference so I can see where I'm coming from, and where I'm going to with the print. I make notes on the backs as I'm working so I know what succeeded or didn't about that particular print.
I have heard the same explanation for using an enlarging lens just a little longer than normal so that you are in the center of coverage. I use a 150 for 4x5 and a 210 for 5x7.
I save as many of my rejects as possible to use as tests for toning etc.
No escaping it!
I must step on fallen leaves
to take this path
Good Evening, Chuck,
I agree that the rejects should usually be saved. Completely fixed and thoroughly washed, they have another useful function which hasn't been mentioned. If you drymount prints, placing a reject (or just a blank sheet of thoroughly processed paper) on the [I]back [I]side of the mount board will balance out any curling tendency.
Also, if you have occasion to use prints in a situation where they will be routinely passed around or handled, simply drymounting a waste print on the back of the "user" print makes a nice stiff package which holds up to handling better than an unmounted print; again, the opposing pull forces of the back-to-back sandwich balance and make for good flatness. All this can apply either to fiber or RC materials.
Longer lenses are great when you're making smaller prints. Gives you a little extra room. OTOH if you're making big prints the long lens will limit you.
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105mm lens can cover up to 6x9cm negs.
Reject prints are nice to have because you can see your growth and progress in them over time.
What works for you, may not be the same as another photographer..
I never throw anything away, it amazes me, how handy things come in, in future printing sessions...I keep them all in a file with notations about why they were not acceptable, which sparks my mind when something goes wrong again.
Longer lenses have some advantages, and one disadvantage for photographera with short arms.
I rarely throw anything away. One never knows when an old print or piece of equipment will be useful. Obviously, I'm not married.
Whew wee!!! Jim I am married, but got smart and built a separate building to keep all of my mistakes in!
Originally Posted by Jim Jones
I tried yesterday making 6x9" prints from 6x9cm negatives with a 110mm lens. Couldn't do it - the focus rail impacted the easel. So I switched to the 150mm lens, and had no problems.
In that case it was not about coverage, image circle or anything else "optical". Merely working distance.
-- Ole Tjugen, Luddite Elitist