M6TTL Exposure Questions -- FOLLOW UP

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I just got back the latest batch of processed negs and contact sheets from my trip to GA last weekend, following my question posted last week on exposure problems I've been having with my new M6TTL. Since so many of you were patient and extremely helpful with suggestions to hone in on the problem, I thought I'd let you know how it went:

1. All color neg (Fuji NPH400, shot/process normal) had realtively spot on exposure. Mediocre shots, but perfectly exposed!

2. Ilford Delta 3200 (shot/process normal) - pretty good exposure, contact sheets are a little grey, but the negs themselves look good and the lab says they'll print great.

3. Ilford Delta 3200 (push 2 stops) - better than I expected! A few 8x10 enlargements show good exposure and contrast (blacks are rich black and whites are white). Grain's no bigger than a Volkswagon, as you'd expect. (Read that Selgado oftern resorts to pushing Delta 3200 to 12,800, so I figured what the heck. I discovered that I'm no Selgado. 'Course, a Georgia wedding doesn't have the same depth of subject matter as a few years in Somalia will give you).

4. Tri-X 400 (shot sort of normal) - one roll fine, one roll horribly ruined due to light leak exposure. Can't figure out how it happened, but I recall that it was 2:00am and I'd tipped back more than my share (is it possible I replaced the baseplate without fully shutting the back cover?!?!)

5. Ilford Delta 400 (shot/process normal) - here's where it gets interesting. These rolls seemed consistently overexposed by about one stop. I spoke to the lab technician (again, I'm using a very good LA pro lab), and he said he shoots Delta 400 frequently and has the same problem! He showed me that the negs are well within the range for great prints. Mind you, this is the second pro lab I've processed Delat 400 with, so I don't think it's a processing "error". Since the negs are fine, I'm not too worried about it, but I wondered if any of you experience similar results with this film?

Bottom line - my "exposure problem" seems to be getting resolved. Got 4 or 5 decent enlargements out of the weekend. Now if I could just shoot more sober...

-- Eric Reid (eric_reid@lkshore.com), November 09, 2001

Answers

> Ilford Delta 400 (shot/process normal) - here's where it gets interesting.

I presume this is the new version of Delta 400. I get EI 400 for an exposure that gives .10DU above fb&f for Zone I, film developed in D-76H 1:1, 1:3 and Ilfosol-S 1:14, "normal" contrast, meters calibrated to "sunny f16" with an Expo-Disc. IOW, for me at least it's an EI 400 film, giving densities comparable to HP5+.

So here's what I suspect happened...

Ilford recommends DD-X developer for the film, or the large-volume equivalant DD...and this developer usually give a 2/3 stop _increase_ in real speed with EI 400 films...so I think the lab most likely used the recommended developer and perhaps overdeveloped it a little, and the result was that your film was overexposed by around 2/3 stop plus maybe a little overdeveloped.

So..I'd suggest you ask what it was developed in and how it was developed; you could then either ask that it be developed in something else or just use it as an EI 640 film.

Why would Ilford recommend a developer that would result in film being overexposed because it increases the "real" speed? I think most film is given nominal or less exposure, so if the speed is increased a little the film that would've been underexposed will give _much_ better results while film that's given an EI 400 exposure won't be significantly degraded.

Along those lines, several minilab operators have told me that they usually run development times a little long (which increases contrast) because so much of the color neg film is underexposed.

-- John Hicks (jbh@magicnet.net), November 09, 2001.


RE: 4)

Most likely. I did this at least once myself back when I was still learning to load the M4-2. In broad daylight and not 'under the influence'! Fortunately I caught it after 4 frames and reloaded.

RE: 5)

So try a roll bracketing everything at 400/500/640/800 (process normal) and see what happens (or if it's too much hassle to mess with the ISO dial every frame, meter/shoot at 400 and shoot a half and a full stop under as well.

I shoot ALL my films at something other than what's printed on the box - and not necessarily a consistent amount plus/minus from one film to the next.

-- Andy Piper (apidens@denver.infi.net), November 09, 2001.


John and Andy -- Thanks for your detailed responses. I appreciate it. My lab is friendly and easy to work with, so I think I will engage them in a discussion of their process on the Delta 400 (it is the new version, BTW). They mentioned that they treat it differently than Tri-X, but I didn't have the knowledge to probe on how exactly they handle it. I'll take your info and ask. Also, I think I'll rate it up 1/3 stop for a roll or two and see how that goes. In any event, the latest batches a shot have resulted in useable negs, so I'm much less concerned. Is it really true, however, that slightly overexposed is generally "ok" and in any event better than underexposed?

-- Eric Reid (eric_reid@lkshore.com), November 12, 2001.

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