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12-24-2021, 02:09 PM   #1
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time and aperture

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what is the correct way to get the aperture on the enlarging lens.. i was under the impression that i was to put something on the carrier, turn it on to focusing mode, set my contrast, then adjust to sharpness.

And how do i correctly set the enlargement time ... longer SHOULD give better print image if you have a darker image?

12-24-2021, 02:30 PM   #2
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First, open your enlarging lens all the way (maximum aperture). Do your critical focusing this way using a focusing aid if available. Then, start with an aperture somewhat closed down from wide-open. That will increase the sharpness of your image (don't print with your lens wide open).

It would be good if you have an enlarging print scale which will allow you to get close to the proper exposure in one test exposure. It depends on the paper being used, but with such a scale, start with a 60 second exposure at say f8. If all your scale results are too light, drop your f-stop to f5.6. If everything is burned out, cut the exposure in half by increasing your f-stop to f11. You should be able to find an exposure where a good looking exposure scale results with one sector showing a good image tonal range. Use that sector factor to determine the actual time needed without the scale. Once you get close, it's probably best to leave the lens aperture at some set value and play with exposure time unless you find the time is impractically short or long - then you can resort to changing the lens aperture. Smaller (higher f-stop) means a lighter print. Larger (lower f-stop) means a darker print (these assume you're printing negatives and not making positive prints from slides).

It will take a little while and some work to get a feeling for the negatives and the paper you're working with. Be sure to write down the exposure time and aperture when you begin getting good prints and use this as a future starting point. There will almost always be some fine tuning required from shot to shot. If you change papers, the last usable exposure can be a good place to start with the exposure scale to find out how that new paper will behave (also refer to paper speeds if they're listed).

The other thing that can be helpful is an enlarging meter. This takes a reading of a blurred image and approximates the exposure required. It also allows you to repeat an exposure very accurately. You can certainly get good prints without one, but it takes more work and trial-and-error. You can accomplish the same thing as an exposure scale if you start a test print and sequentially cover (or uncover) portions of the paper at known intervals, noting the times used for each section, but that too, can result in more work. When you've mastered B&W, may want to move on to color but there are more variables to control with color and the materials are considerably more costly. At that point, it would be wise to invest in an enlarger exposure meter so you don't need to waste paper finding the proper exposure (it can also involve a color analyzer to get the correct color).

Finally, the best exposure is the one which gives the most pleasing image to you (or your customer if your selling your work). There are many combinations of time and aperture which will do essentially the same thing so it's best to settle on changing one and leaving the other alone until you find a good looking image, but after you find the best exposure, you'll get to doing better in no time and get a sense of what to use.

Hope this helps - good printing!

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Last edited by Bob 256; 12-24-2021 at 02:56 PM.
12-24-2021, 04:22 PM   #3
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Also, Gossen used to make an enlarging meter attachment for the Luna Pro, a great meter. It worked great.
12-24-2021, 05:47 PM   #4
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maximum aperture, lens set to the lowest number on the dial, in this case 3.5. It just makes a nasty blur on the easel i just cant make heads or tails of. I have to step it down from 3.5 to 8 or 11, id have to hook everything up and get an image adjusted on the table to be sure.. the 90mm went from 5.6 to 32, but didnt give an image i could even SEE until f/22, but nothing clear and focused until i hit f/32.

I was thinking of one of those exposure counter overlay charts,, but from what ive seen on other websites it needs to be done for EACH image..

And no one ever says how to use one when you dont have a consistent light/dark area in each SECTOR of the pie chart it produces. meaning if the 12 second zone is on a white spot, and the only dark zone is on 30... how to compensate for actual time touse

12-24-2021, 08:05 PM   #5
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If you're getting a blur on the easel, it isn't due to the aperture setting. You're way off the focus point. Either your lens plate or the bellows, is the wrong extension for the lens you're trying to use. Set your easel on something to raise it closer to the enlarger lens and see if you get a better or worse focus. If the focus improves, you need to move the lens closer to the negative for the regular position of the easel. If the focus gets worse, you need to move the lens further from the film. It may be that the bellows on the enlarger was designed for a different set of lenses and it won't extend far enough. You can put an extension on the lens mount if that improves focus.

The reason you're getting a sharper image at those very high f-stops is due to the depth of field increasing with smaller aperture, but that isn't the way to focus for a print. You have to move the lens relative to the negative to get a good focus at maximum aperture before you can do any worthwhile enlarging.

You need a print with small details so bits and pieces of the image with similar exposure fall into all of those sectors. Then you can compare sectors to get a starting point which might have to be fine tuned by trial and error. Usually, if negatives were exposed correctly, one setup with a sector disk will suffice for the entire roll because you'll be making test prints and fine adjusting each frame anyway.

First things first however. Get your enlarger to produce a sharp image wide open.

Last edited by Bob 256; 12-24-2021 at 08:13 PM.
12-24-2021, 08:14 PM   #6
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QuoteOriginally posted by Bob 256 Quote
If you're getting a blur on the easel, it isn't due to the aperture setting. You're way off the focus point. Either your lens plate or the bellows, is the wrong extension for the lens you're trying to use. Set your easel on something to raise it closer to the enlarger lens and see if you get a better or worse focus. If the focus improves, you need to move the lens closer to the negative for the regular position of the easel. If the focus gets worse, you need to move the lens further from the film. It may be that the bellows on the enlarger was designed for a different set of lenses and it won't extend far enough. You can put an extension on the lens mount if that improves focus.

The reason you're getting a sharper image at those very high f-stops is due to the depth of field increasing with smaller aperture, but that isn't the way to focus for a print. You have to move the lens relative to the negative to get a good focus at maximum aperture before you can do any worthwhile enlarging.
Bob, in the horenstien black and white photography book, he says that the size of the print image on the photo paper is controlled by the distance from the lens to the photo paper, if you want it larger or smaller, move the lens stage up and down to do so..

At this point using the 50 mm focal length beseler lens, I would have to cut the top bar off the rails, and the corner brackets off to get enough height, the 35mm spot on the scale puts the negative about 8 inches from the beseler labeled trap door.
12-24-2021, 08:21 PM   #7
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QuoteOriginally posted by filmmaster Quote
Bob, in the horenstien black and white photography book, he says that the size of the print image on the photo paper is controlled by the distance from the lens to the photo paper, if you want it larger or smaller, move the lens stage up and down to do so..

At this point using the 50 mm focal length beseler lens, I would have to cut the top bar off the rails, and the corner brackets off to get enough height, the 35mm spot on the scale puts the negative about 8 inches from the beseler labeled trap door.
That's correct. Are you saying with the enlarger at its maximum height your image is too small? If that's the case, you need to go to a shorter focal length lens. That could be why you can't get a good focus also, because the lens can't be positioned close enough to the negative for a proper focus (or you could have it too close and it needs to come away from the negative which will also make your image smaller as it comes into better focus). What is your negative size??

Just to give you some idea - If your negative is 35mm full frame, a 50mm lens should produce a x10 magnification when the lens is 55mm away from the negative and that would put the easel 550mm (about 22 inches) below the lens, resulting in about a 15" x 10" image. To get a x25 magnification, you would have the lens 52mm from the negative and the lens/easel distance would be 1300mm or about 50 inches (and the image size would be about 37.5" x 25".


Last edited by Bob 256; 12-24-2021 at 08:48 PM.
12-25-2021, 07:51 AM   #8
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You’re getting something very wrong here, the instructions for the enlarger say with a 50mm lens and 35mm film, it can make prints up to almost 20”x30”. You need to read them!

http://www.jollinger.com/photo/cam-coll/manuals/enlargers/beseler/Beseler_23C_II.pdf


Getting the correct exposure is a matter of making a test strip (or print) for the negative at the amount of enlargement you want. It’s quite simple to do, no expensive exposure meter for enlarging needed. This describes the process simply:-

https://www.amateurphotographer.co.uk/technique/expert_advice/essential-guid...printing-44370

Note the article shows making a test print - I was always more parsimonious and used a cutting no more than 2” wide and 6” long. YMMV
12-25-2021, 08:47 PM   #9
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i have the dual dichro s head installed, i cannot physically raise the enlarger past the 4 3/4 heigh mark on the rail height scale. At that point, the top of the dual dichro s head is an 1/8 from hitting the corner brackets at the top of the rail
12-26-2021, 02:05 AM   #10
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QuoteOriginally posted by filmmaster Quote
i have the dual dichro s head installed, i cannot physically raise the enlarger past the 4 3/4 heigh mark on the rail height scale. At that point, the top of the dual dichro s head is an 1/8 from hitting the corner brackets at the top of the rail
Does the dual dichro head remove the ability to focus? Focussing is manual on these enlargers, there’s a knob on the plate which the lens is fastened into which moves the lens, lens board, bellows etc up and down without moving the dichro head or the entire enlarger up or down and I’ll bet yours is clamped down at minimum extension. Try it. I’d show you the process myself but I live far far away. The only autofocus enlarger I knew of was a Leica job and terrifyingly expensive. edit: and the Durst A300 series
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Last edited by StiffLegged; 12-26-2021 at 02:56 AM.
12-26-2021, 08:45 PM   #11
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the dual dichro s head only deals with creating light, and the filters. to install one must remove lamp holder part 1, and screw 14. it slides down onto housing part number 2. And rests directly upon the small ledge you see above the flip up door labelled as part 3.
12-27-2021, 01:28 AM   #12
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None of which has anything to do with focussing. Have you managed that yet?

Here’s a picture of the Dual Dichroic head on a 23Cii and it’s not fouling these brackets at all. I’m at a loss as to what you’re doing. Installation instructions for the head are at:-

http://www.jollinger.com/photo/cam-coll/manuals/enlargers/beseler/Beseler_DualDichro23_head.pdf

Oh, and the difference between the S model of the head and the ordinary model is the S has a stabilised power supply. That’s all.

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Last edited by StiffLegged; 12-27-2021 at 04:45 AM.
01-01-2022, 09:55 AM   #13
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My method (before any specialized equipment) was to make a test print from small, 5x7 inch vairable contrast paper with 3 exposure times across the print. I would guess the grade of paper filter to dial in based on a visual inspection of the exposure/development on a lightbox

Usually two or three attempts yielded a good exposure and paper contrast I would want for that print. It is best to make final evaluations on a dried print. I would record exposure, paper grade and enlarger height on the back of the print. I would use this info as a very good starting point to make a larger print by calculating the new exposure from the inverse square law.

F8 was my standard apeperture but I would stop down more if I was correcting converging lines by lifting up one end of the easel or if I need more exposure time to do some burning/dodging in different areas of the of print.
01-02-2022, 09:36 PM   #14
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if i take the dichro head off, it goes all the way up the scale no issue.. but the head is in the way. I have the standard SHORT version of the 23c series 2
01-05-2022, 10:24 AM   #15
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QuoteOriginally posted by filmmaster Quote
if i take the dichro head off, it goes all the way up the scale no issue.. but the head is in the way. I have the standard SHORT version of the 23c series 2
The point is, you shouldn't need to do this if you have the proper lens and arrangement. You probably need a shorter focal length lens but from my perspective, I (and maybe some others here) don't know what you're doing unless you provide more information (negative size, paper size, lens focal length, etc.). Maybe take a photo of your enlarger arrangement and include it for reference??
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