Transmitted light grey wedge

Ewald · 2013-06-11T01:07:24+00:00

Hallo Gemeinde, Wo kann man einen Durchlichtgraukeil mit 8 oder 11 Stufen kaufen, zwecks densitometrischer Auswertung von Planfilmen (alle Filme) am besten...

Ewald

Hello everyone, Where can I buy a 8- or 11-step transparency grey scale for densitometric analysis of sheet films (all types of film), ideally in 4×5" format? l-G- Ewald

piu58

[size=8][font=arial, helvetica, sans-seri<sup>Stouffer. They have all sorts of varieties:</sup> [/size] ? [size=8][font=arial, helvetica, sans-seri<sup>http://www.stouffer.net/TransPage.htm</sup> [/size] ? [size=8][font=arial, helvetica, sans-seri<sup>Shipping to Germany is no problem; I asked them to send a letter rather than an expensive parcel.</sup> [/size]

SxDx

I was just about to recommend Stouffer as well. These are in 4x5" format, so you can use them, for example, in flat film cassettes as a 'sandwich' with the film you're testing: http://www.stouffer.net/Photo.htm € I don’t know of any with 8 or 15 stops in 4x5" format, but the Stouffer in 4x5" is available with 21, 31 and 41 stops, i.e. in increments of 1/2, 1/3 and 1/6 EV or 0.15, 0.1 and 0.05 logD.

Ewald

I was just about to recommend Stouffer as well. These are in 4x5" format, so you can use them, for example, in flat film cassettes as a 'sandwich' with the film you want to test: http://www.stouffer.net/Photo.htm € I don’t know of any with 8 or 15 stops in 4x5" format, but the Stouffer in 4x5" is available with 21, 31 and 41 stops, i.e. in increments of 1/2, 1/3 and 1/6 EV or 0.15, 0.1 and 0.05 logD.

Hello SXDX, Many thanks, I’ve found everything, including the order address. I’ll go for the uncalibrated 4x5" with 21 stops. It’s the sheet film format that matters to me. That way, I don’t have to fiddle around with slider movements for a maximum of 5 exposures on the sheet film, but instead have precise contact copying with 21 stops. Best regards, Ewald

Ewald

I was just about to recommend Stouffer as well. These are in 4x5" format, so you can use them, for example, in flat film cassettes as a 'sandwich' with the film you want to test: http://www.stouffer.net/Photo.htm € I don’t know of any with 8 or 15 stops in 4x5" format, but the Stouffer in 4x5" is available with 21, 31 and 41 stops, i.e. with increments of 1/2, 1/3 and 1/6 EV or 0.15, 0.1 and 0.05 logD.

That was a duplicate

AndreasJung

Yes, I'm interested in that too – how do you go about it with 4×5 sheet film?

Ewald

Yes, I’m interested in this too – how do you go about it with 4×5 sheet film?

Hi, There’s a guide by Otto Beyer. Following his method, I layered an Acros 100 and the Stouffer wedge one on top of the other and slid them into a cassette. It doesn’t fit in every one. It worked for me in a Lisco Mark II. Then I hung an opaque screen against the window, set the exposure to minus 5 stops, and took the shot using the same shutter speed and aperture combination. I developed the film without a computer, using only darkroom supplies and a calculator, following Manfred Anzinger’s method. I’d recommend ‘studying’ both authors beforehand. Best regards, Ewald

Ewald

€ <blockquote class="ipsBlockquote" data-author="SxDx" data-cid="16119" data-time="1370924584"> <div> I was just about to recommend Stouffer too. These are in 4x5" format, so you can use them, for example, in flat film cassettes as a sandwich with a film you want to test: http://www.stouffer.net/Photo.htm € I don’t know of any with 8 or 15 stops in 4x5" format, but the Stouffer in 4x5" is available with 21, 31 and 41 stops, i.e. in increments of 1/2, 1/3 and 1/6 EV or 0.15, 0.1 and 0.05 logD. </quote> HelloSXDX, Many thanks, I’ve found everything, including the order address. I’ll go for the uncalibrated 4x5" with 21 stops. It’s the sheet film format that matters to me. That way, I don’t have to fiddle around with slider movements for a maximum of 5 exposures on the sheet film, but instead have accurate contact copying with 21 stops. Best regards, Ewald € </DIV> </BLOCKQUOTE> Addendum: Exposing five stops in f-stop increments onto a sheet film is easier than fiddling with a transmitted light grey wedge and sheet film in a cassette. The results are identical in any case. With the Stouffer, you have more values, but five (-2, -1, 0, +1, +2) are sufficient to determine the gamma value. Best regards, Ewald

Tandemfahren

Hi, That’s true, but with the grey scale in thirds, you can read the actual speed straight away. I wouldn’t necessarily get hung up on the gamma value alone; its informative value is rather limited. You can predict the image result more accurately if you know the entire curve. € By the way, I think it’s great that you’re taking such a systematic approach to sensitometry; it really does help when taking photos. Keep it up! € Frankgröße

Ewald

?

Hi, That’s true, but with the grey scale in thirds, you can read the actual speed straight away. I wouldn’t necessarily get hung up on the gamma value alone; its informative value is rather limited. You can predict the image result more accurately if you know the entire curve. ? By the way, I think it’s great that you’re taking such a systematic approach to sensitometry; it really does help when taking photos. Keep it up! ? Frankgröße

Hi, I won’t be buying another one, though – that cost me 45 quid. My previous 35mm film evaluations have led me to the point where I now always know in advance whether the film has turned out well. With sheet film, I didn’t know how to proceed at first, but now I have my own method for performing exposure on 9 strips on a single sheet. With the Stouffer, it’s even easier now, of course – just one exposure and everything’s done. Unfortunately, I only have a basic darkroom timer (Kaiser Automatiktimer); it’s good as a timer but the sensor is technically weak and only reacts to the middle sections of the grey scale. Cheers Ewald

Tandemfahren

Oh, I’d completely forgotten – your Stouffer wedge is in half-stops, isn’t it? How on earth do you get any usable measurement results without a proper densitometer? Just using the Labeli? What does that even show? Mine only displays seconds (which I then have to calibrate myself for the specific paper).

Ewald

Oh, I’d completely missed that – your Stouffer wedge is in half-stops, isn’t it? How on earth do you get any usable measurement results without a proper densitometer? Just using the Labobeli? What does that even show? Mine only displays seconds (which I then have to calibrate myself for the specific paper)

In half-stops, that’s right. My lab meter (Kaiser Automatiktimer) also gives seconds, but it can’t manage to display more than the 6 middle ranges (3 stops down and 3 stops up). When I want to measure the fog, I can just about get to the middle; it can’t handle the dark streaks beyond that. So I needed a better meter. But it’s certainly good enough for measuring contrast. You don’t need a Stouffer for that alone. Best regards, Ewald