Oy vey, I wish I knew!
Oy vey, I wish I knew!When I look at this photo of the negs (and I flip the step wedge 180) the laptop ends up about 2 2/3 stop below step 6 and the white paper ends up about 2 1/3 stops above step 6, which is exactly where they should be. So whatever you did here is exactly right and Keep Doing It!!!
So, you are saying that there is a slight lack of contrast in that set of negatives, but exposure wise, it's good...right?Previous post deleted.
Edit: actually, I am mistaken in the deleted post. The step wedge is calibrated in 1/2 stop increments. So the white paper and the black laptop are actually about 1 stop away from middle gray.
Do I get to say "I told you so" now??And you'll never believe this; I'm embarrassed to say it but since I'm baring my soul here and my mistakes are public...I can read newsprint "just barely" through the Bergger and the Tri-X negatives, just as the folklore says I'd be able to. The Bergger moreso than the Tri-X but even the Tri-x I'm able to.
Lol...yes you do.Do I get to say "I told you so" now??
I don't know why you would be embarrassed. You seem to be well on your way to success. Just because there was some help on the way, doesn't mean you shouldn't feel good about it.
Wow, very informative!Hi... well some very good support has come your way. Having looked over the numbers I'm of the opinion that your development process is about right. For all three films you have achieved +/- .65 Contrast index. Ilford suggests this should be the targeted result. Your density readings appear inconsistent in respect of exposure. So too the variation from base reading across the ISO changes is not nearly as linear as might be expected with density near the middle of the range. For instance:
To calculate the "ball park" Contrast index: obtain the difference between the achieved density readings of the 400 and 100 ISO negatives and divide by the expected 2 stop density variation being about 0.6 density. Thus, at box 400 ISO = 1.3 and 100 ISO = 1.7 - variation 0.4/0.6 = .67 - pretty good.
- Film rated at box & developed as recommended should result in a density variation of close to .3 for each stop of exposure. So, the expected density, of say 0.72 would rise up to the top of the curve by about 0.3 for every ISO reduction. Your ISO changes from base are @ ISO 400 density =1.3(box ) @ ISO 200 density +0.16 (half a stop not 1) and ISO 100 + 0.4 (1.3 stops not 2) indicates exposure is placed near the top of the curve representing a metering or technique error. This negative is at least 2 stops over exposed, density should be 1.3 minus 0.6 = 0.70 (refer Ralph's suggestion) and to some extent explains why the negative rated at ISO 100 and under developed 30% - see point #3 below, is "almost" right! And, not to say your normal metering should be to consistently over expose and under develop to this degree.
- The same observation is made for the film over exposed 1 stop and under developed 15% as the readings are the same as those of the film rated and developed per manufacturer recommendation. Something wrong here...
- Interestingly the film under exposed by 2 stops and underdeveloped 30% measures as expected with about .3 density change for each variation of the ISO and Contrast Index 0.65.
If, as Ralph suggests, a negative having 0.72 density is the target then clearly something is amiss with your technique and/or your equipment (meter/camera). So rather than trying to read a newspaper thought the highlights of your negative - one step at a time. Stay with manufacturer recommended ISO setting and development strategies & perfect 1 film/developer combination before widening your repertoire. Keep us posted on your progress... Fred
I always err on the side of overexposure by 1 stop as a minimum. (setting meter to 200 on 400 film) I also try and meter for the shadows.
Lol..I may have but it's not working out well. I'm going to start from square one again and go from there.Standard practice for a lot of people is to over expose by one stop and decrease development time by about 25% to get better shadow detail. You seem to have discovered this without looking for it!
Steve.
Yes, I've read that and now i've wondered what's suitable for me considering all of the variables. Once I start from the manufacturer's published times and such, then I'll find out. Whatever I do find out, I'll certainly come back and share.In practice, things may end up one stop slower than box speed. :-|
Yes, I've read that and now i've wondered what's suitable for me considering all of the variables. Once I start from the manufacturer's published times and such, then I'll find out. Whatever I do find out, I'll certainly come back and share.
Thanks.Any development method that needs any device is a deviation from manufacturers devices and their methods. Happy testing.
Thanks Doremus, I actually do know that much so far. I learned that on the APUG one day quite a while ago, but I didn't realize the part about doing it with the enlargement, thanks for that info.rpavich,
Learn how to make a proper proof (if you are not already) to help with zeroing in on your exposure and development. A proper proof is one that has the minimum exposure to have clear areas of the film reach maximum black in display lighting (the lighting is important here). Make a test strip of your film on a strip of paper a bit wider than the film itself. Examine the black of the film rebate on the edge next to the paper that was not covered by the film. When the black of the rebate matches the black of the exposed, uncovered area, that's the right exposure time for your contact proof sheet (keep f-stop and enlarger head height equal of course). You can easily compare exposures and different development times on one sheet this way
Do the same with an enlargement by including the film rebate and a bit of nothing at all at the edge of the neg carrier. Make your test strip and, again, compare the black of the exposed uncovered black with the black of the film rebate. Your "proper enlarging time" will again be that at which the blacks match. You will likely not want to use this exposure to make a fine print, but it will let you know how you are doing on exposure and development.
Best,
Doremus
Im using it per directions, i take the base reading throught the clear part of the neg between frames then at the intended targets.Hi... When metering are you using an incident light meter reading or reflected? I havn't asked you how you go about establishing the zero base density using your R.H. Design enlarging meter... before reading the negative? This is one of the last pieces in the jigsaw. When reading are your lights & safelight/s on of off? Fred
Incident.Just to follow up... How are do you meter your test area? Incident or reflected? Fred
Fred,I think the issue resolves itself with this information. Your test target is used mainly for computer generated imaging the "grey" area being used for white balance purposes. This "middle grey" is lighter than the average reading obtained using the meter in incident mode. Probably the Sekonic is calibrated to a 14% rather than the accepted 18% grey card reading. Hence, reading the density off the "grey" area, which I believe is nearer to 20% reflectance, will report a higher density than had you initially metered directly off the grey of test target. This means, your exposure is about spot on!
Check this by taking an incident reading as usual then, using the same meter read the grey area directly (get as close as you can without influencing the light falling on the target). Lastly, use your spot meter to measure directly off the grey area. I'd be surprised if you cannot close the apparent 2 stop over exposure difference in the exposure readings. Fred
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