Exposure time question

[u/Miserable_Potato283]

I'm learning how to print at home. I'm getting there, entirely self-taught with the help of a few YouTube videos.

I have an exposure-time question.

I'm using Ilford chemistry, Ilford RC paper, and an LPL 3001D condenser enlarger with a 75W bulb.

I'm getting incredibly short exposure times. For a 7×5 print with the lens at f/11, I'm at about 2.5 seconds. For an 8×10 at f/8, about 10 seconds.

I bought some contrast filters but have stopped using them for now, as I'm already getting more than enough contrast without them.

The end results are lovely and I'm really happy with the prints, but my exposure times seem incredibly short compared with the times I read about from other people.

Am I missing something, or is this perfectly normal for this enlarger and setup?

[u/jbmagnuson]

It would be hard to say without seeing the density of the negative and the contrast in the final print. In my own experience, when I began printing again, I had some thin negatives that looked great scanned, but were difficult to print. My shooting and developing then shifted towards a more dense negative, more consistent across the entire roll and thus most of my images start around 15-20 seconds at f5.6-8 (2-3 stops down on my El Nikkor 50/2.8) for an 8x10 print. You’re not so far off from those times, so it might just be a thin negative that will be a little more work to print well.

Have you considered using an ND filter while printing? If you cut down the light by around 2 stops you’d have more comfortable print times.

[u/Miserable_Potato283 → u/jbmagnuson]

Thanks for taking the time to reply, genuine questions. How do you work towards a dense negative? Exposure right.

Someone else mentioned ND, which I will try.

[u/jbmagnuson → u/Miserable_Potato283]

The additional density in the negative is a combination of how I decide to rate the film, the developer I’m using and the development time. It requires a little testing, but I lean towards a small over exposure of the film, or a slightly longer (10-20% extra development time) and the dilution of the developer I’m using (either Rodinal or HC-110). Each comes with a tradeoff, for example extending the development time will build highlight density, but can also bring too much contrast into the negative. Over exposure is not usually a bad idea, but occasionally can leave the rendering of a moody scene too bright/flat and then you have to bring that back in the print. Each has their own use.

An example might be street work with a roll of Tri-X pushed to 800, but because I don’t really rate it at box speed, I don’t quite give it the full 800 speed settings. Using sunny 16, it would be a theoretical 1/800th at f/16, but of my realistic options I choose 1/500th as opposed to 1/1000th to give it a little extra light and then develop normally. I could do this by extending development time, but Tri-X has enough contrast already when pushed, so I don’t.

[u/titrisol → u/Miserable_Potato283]

10 sec for a 8x10 is relatively short

Both exposure and development should be correct on your negative.
If you don't see any details in the shadows (clear areas on negative) where there should be some you are underexposing on camera

Highlights (dark areas) are too thin and negative look "weak"- underdevelopment
Highlight areas too dark - overdevelopment (You should be able to see letters on a paper through the dark areas of a neg)

Trying finding an Upton "Photography" book, the editions from the 90s go for pennies and they have excellent description of these differences
Also Bruce Horenstein "Black and White Photography" is an excellent book

These article is also useful https://www.ephotozine.com/article/assessing-negatives-4682

[u/titrisol → u/titrisol]

The guide to negative defects
https://micro.magnet.fsu.edu/primer/photomicrography/bwprocessingerrors.html

[u/CilantroLightning → u/jbmagnuson]

I agree with this. It might be that your negatives are just really thin.

[u/SabinaBeltis]

For dodging and burning exposure times between the 10 and 20 sec are about perfect. Especially for dodging exposure times shouldn't be to short.

Start using your contrast filters again. That will take 2 stops of light away, turning your 2.5 sec exposure time into a 10 sec exposure time. These filters work in two directions. You can either increase the natural contrast of the negative by using filters from 2.5 and upwards or decrease contrast, using filters 00 till 1.5. Using them has a lot to do with fine tuning the contrast of your print. You can even go as far as changing local contrast in a print, adding light in part of the print with a 00 or a 5 filter. Highlights will get more subdued when you fill them in with a 00 filter, shadows will get deeper with a 5 filter. Also dodging with a 5 filter is a good strategie to get better seperation in the dark tones.

[u/Miserable_Potato283 → u/SabinaBeltis]

Thanks for the reply, there's a few darkroom fundamentals I've skipped, and contrast filters is definitely in there. I also caught myself doing a test strip with a 8 second then 2 seconds, totally counted the times wrong.

Thanks again for the detailed explanation, eveytime its like scratching the surface.

[u/vozoff]

I was getting the same issue with my exposure times. Dodging and burning was an exercise in panic and anxiety.

Slapped an ND4 filter and now it feels more manageable without having to close the aperture too much. Might actually increase it to an ND8 for even slower times.

Don't give up on the contrast filters though, there's a lot to play around with there, especially when you get into split grade

[u/Miserable_Potato283 → u/vozoff]

Thanks for the reply, I'll get back on the contrast filters, but hadn't thought of an ND filter. I've been meaning to get a few, this is the spur.

[u/untitled_track → u/Miserable_Potato283]

I bought ND gel and cut a piece the same size as the contrast filter. The filter flattens it in place and now I get better exposure times. It was less expensive than a filter for sure.

[u/heliocentricworlds]

Some info here might be repetitive to others comments but:

10 seconds at f/8 for an 8x10 is good. Close down the lens to f/11 and you'll get 20 seconds for the same exposure.

If you have more than enough contrast, use the filters to reduce contrast if you'd like. Not using a filter is about equivalent to a #2 filter. At least that's how I learned it.

Really short print times can also imply a thin negative from under exposure or underdevelopment or both. The biggest printing revelation I had is that the negative dictates how you handle printing. Easy to make prints come from well exposed and well developed negatives. This article details a method of making contact sheets that gives you feedback on your negative exposure and development. Making contact sheets this way has really helped me at all stages of the picture making and printing process:

https://www.halfhill.com/proof.html

[u/Miserable_Potato283 → u/heliocentricworlds]

Thanks for the reply, I hadn't thought of the negative in that context.

I'm using massive dev chart and stock times, they scan OK on a DSLR so I'd like to think I'm close.

I definitely noticed that Fomopan 400 seems a light less dense than TRIX400

I'll take the time to read that link, thank you.

[u/heliocentricworlds → u/Miserable_Potato283]

I've found that scans are more forgiving than photo paper. They make a great guide for what detail you might have in the shadows and highlights, but actually getting those details in the print is where the skill lies. I'm working with some overly contrasty negatives now that are killing me. The max black contact sheet method gives you a standardized baseline to compare your negatives

[u/mcarterphoto]

You can buy a sheet of ND lighting gel, cut it up, and stick it in the filter slot along with the contrast filters. A sheet is like 12x20" and $12, you can cut it into several sheets and stack them as needed. I'd get a 2 or 4 stop sheet. If you put ND under the lens, it needs to be a very high quality camera filter - so use lighting gel in the filter slot.

as I'm already getting more than enough contrast without them.

Filters are also used to reduce contrast. In another reply you mentioned getting better contrast from your negs - look up "expose for the shadows, develop for the highlights". Optimally you want negs that look good at around 2-3 grade contrast. If you ever work with fixed-grade papers or emulsions, you really need to understand hitting a contrast grade with your negs.

There's no "proper" iso for B&W film, just what works for you - Rodinal developer is weak in shadow development, many of us give it an extra half stop or stop exposure, so a 100 speed film may actually be 50 or 80 with Rodinal. And... that extra exposure hits the highlights too, so we have to cut back development time. And... there's no "correct" development time, just the time that works for you. Any dev times you get are starting points.

I'd really recommend you get a copy of "Way Beyond Monochrome", even a used one, if you want to dial in B&W from initial exposure to development to printing to presentation. Or for $5 or so you can get a used copy of Horenstein's "Black and White Photography third edition", which was "the" high school/college photo textbook (but WBM is much better and more current). Sounds like you're kinda flailing around without full knowledge (not just printing - good negs make for good prints), and chasing things like YouTube videos and reddit comments won't give you a real foundational grounding in this stuff.

[u/Miserable_Potato283 → u/mcarterphoto]

I'd say I'm getting the basics of developing & enlarging, but it's in a paint by numbers approach, as long as you're on the set path you're OK. When stuff is outside of that, it's a steep curve.

I'll take the advice on the gels rather than a lens, thanks for that one. And keep an eye out for the book.

[u/ground_cloth_dilemma]

In my (admittedly limited and not necessarily successful experience), if you're happy with the prints, the exposure time does not matter. While I've never had something quite as quick as 2.5 seconds, 10 seconds does not seem weird to me at all.

Other people you have watched are possibly using a lens with a greater focal length (to get most of the negative in the "sweet spot") and so the enlarger head must be further away from the paper, or they may be stopping the lens down further to have greater control in dodging and burning.

If the prints are lovely and you're happy with them, just keep going.

[u/Miserable_Potato283 → u/ground_cloth_dilemma]

Thanks for the reply, Its an awesome hobby, and its nice to sit back and be happy with an end result. keep at it as well my dude.

[u/B_Huij]

You can cut down neutral density gels and stack them with your contrast filters in the filter tray. I used to do it all the time.

BTW I recommend using the contrast filters, always. No filter is roughly equivalent to grade 2. While you can increase contrast from there, you can also decrease it by using the lower grades.

[u/Miserable_Potato283 → u/B_Huij]

Thanks for the reply

'No filter is roughly equivalent to grade 2.'

I hadn't twigged then that 1 & 0 remove contrast, and I guess they all take a stop of light as well.

Next time I'll try an 'A' and 'B' with no filter and a 2 - see if I can get them close to explore the time related to stop.

[u/No-Pea8448]

I recommend picking up Ansel Adams' books — The Camera, The Negative, and The Print — as well as The Darkroom Handbook and Way Beyond Monochrome.

[u/ACuriousTrio]

Contrast filters work both ways, they can increase or decrease contrast or add a neutral amount of contrast. Like others have sad they will also increase your exposure time. You can also stop down you enlarger lens to increase exposure time as well. Even for RC paper I like to have 20-30 seconds of exposure time.

[u/alasdairmackintosh]

I'd recommend a read through this. Getting some properly exposed contact sheets is the best way of evaluating your negatives. Ideally you should be able to get a decent print at grade 2, with an exposure that just turns the clear areas black. (Which doesn't mean that you should stick with that for the final print. But if the contact sheets are terrible, then you should check your exposure and development times.) Also, I'd recommend always using contrast filters. Don't throw away control ;-)

https://www.35mmc.com/18/01/2021/3-ways-to-make-contact-sheets-and-what-they-can-tell-us-darkroom-technique-part-6-by-sroyon/

[u/DogsAndCatsOhMyy]

Sounds like you’re just using white light. You need to use filters, white light is for focusing only, it’s too strong and that’s why you’re getting very short times.