Ilford ortho plus iso rating?

[Jimi3]

Don't bother with a safelight. Trust the time/temp development method.

Yeah, so it’s not about the development method. Cutting the strips and placing them into the 4x5 film holder in total darkness is time consuming and difficult. It’s also easier UNloading them with a little light.

 

[Jimi3]

Most of our "red" safelights aren't actually ortho film safe red safelights.
View attachment 346424

I checked and the filter is indeed a gbx-2.

 

[MattKing]

I checked and the filter is indeed a gbx-2.

And the film may require a 2.

 

[Jimi3]

And the film may require a 2.

I can’t seem to find the thread, but I had been advised that the gbx-2 is equivalent to Ilford’s recommended safelight for this film.

 

[Jimi3]

And the film may require a 2.

Yeah, looks like according to the chart, a 2 may be recommended. But I did the coin test, exposing up to 3 minutes and got no visible image on the film…

 

[MattKing]

Yeah, looks like according to the chart, a 2 may be recommended. But I did the coin test, exposing up to 3 minutes and got no visible image on the film…

Did you first fog the film very slightly, before doing the test? That is critically important, especially for a lot of ortho materials.

 

[Jimi3]

Did you first fog the film very slightly, before doing the test? That is critically important, especially for a lot of ortho materials.

I did not. How should I go about that?

I shot half a roll in camera for iso testing, and will be developing that tonight. I can repeat the safelight test too.

 

[MattKing]

To lightly fog a bit of the film, take a 2 stop under-exposed picture of a mid-tone surface, then do the coin test on that.
With photographic paper, we just do a test strip and determine what exposure results in a light grey, then pre-expose a safelight test sheet with that amount of light before doing the test.

 

[Jimi3]

To lightly fog a bit of the film, take a 2 stop under-exposed picture of a mid-tone surface, then do the coin test on that.
With photographic paper, we just do a test strip and determine what exposure results in a light grey, then pre-expose a safelight test sheet with that amount of light before doing the test.

Thanks. My darkroom access is limited, so I had to go ahead earlier today and try the test again, just guessing on how to flash the film without overexposing it. So I just flashed an incandescent light on for a fraction of a second, but that was too much and the strips I flashed came out black.

I won’t have a chance to redo the test for a while (again, limited darkroom access), but I did develop my camera exposures, and it looks the best frames were underexposed two stops from iso 80, so 320. So that would explain the overexposure I was originally inquiring about.

 

[pentaxuser]

Matt in the chart you supplied Kodak makes a distinction between a 2 and a GBX-2, the latter being designed for most blue and green sensitive medical X ray film with an apparent common link of green sensitive X ray films but no mention of fast orthochromatic film. However on googling all sources including a number of Photrio members seem to state that the GBX-2 is OK for fast orthochromatic film as well. This is puzzling and would appear to exclude the GBX-2 from fast orthochromatic and render it at least a risk if not completely unsafe for fast orthochromatic film

Is there any kind of a link that makes a filter that's safe for most green sensitive X ray film automatically safe for fast ortho film?

pentaxuser

 

[Vaughn]

Thanks. My darkroom access is limited, so I had to go ahead earlier today and try the test again, just guessing on how to flash the film without overexposing it. So I just flashed an incandescent light on for a fraction of a second, but that was too much and the strips I flashed came out black.

I won’t have a chance to redo the test for a while (again, limited darkroom access), but I did develop my camera exposures, and it looks the best frames were underexposed two stops from iso 80, so 320. So that would explain the overexposure I was originally inquiring about.

Using some x-ray film in the 8x10 awhile back, I noticed that the effective speed of the film varied greatly with the average color of the scene and/or of the light being used. Very fast in open shade (a ton of blue light) and significantly slower in the dense forest (overcast filtered light, browns and reddish browns), for example.

Flashing the film -- might have to resort to taping one piece in a holder in complete darkness and expose it in the camera -- out-of-focus at a plain wall and meter to place the wall on Zone III perhaps.

 

[MattKing]

Matt in the chart you supplied Kodak makes a distinction between a 2 and a GBX-2, the latter being designed for most blue and green sensitive medical X ray film with an apparent common link of green sensitive X ray films but no mention of fast orthochromatic film. However on googling all sources including a number of Photrio members seem to state that the GBX-2 is OK for fast orthochromatic film as well. This is puzzling and would appear to exclude the GBX-2 from fast orthochromatic and render it at least a risk if not completely unsafe for fast orthochromatic film

Is there any kind of a link that makes a filter that's safe for most green sensitive X ray film automatically safe for fast ortho film?

pentaxuser

I'm afraid with Kodak the X-ray film division, and the graphic arts film division and the continuous tone pictorial film division didn't ordinarily compare notes and issue common recommendations. In the past, you normally couldn't even buy those materials from the same sources - those with dealership status in one line didn't have access to the catalogues for the other products and had no way to order them.
The practice in modern times to re-purpose materials designed for radically different uses is quite new.

 

[pentaxuser]

I'm afraid with Kodak the X-ray film division, and the graphic arts film division and the continuous tone pictorial film division didn't ordinarily compare notes and issue common recommendations. In the past, you normally couldn't even buy those materials from the same sources - those with dealership status in one line didn't have access to the catalogues for the other products and had no way to order them.
The practice in modern times to re-purpose materials designed for radically different uses is quite new.

So can I take ít that your conclusion is that there is no way of being sure that for fast ortho film GBX-2 will be definitely be suitable. It may or may not be different from a Kodak 2.

What do you make of various statements that GBX-2 is OK?

It was just that Jimi3 seems to be on the horns of a dilemma about GBX-2 and my question to you and your answer might help him but I accept that in some cases you can't always give a definite answer and this looks like one of them

pentaxuser

 

[juan]

Kodak GBX2 safe light is for X-Ray film. That may be your problem.

 

[MattKing]

So can I take ít that your conclusion is that there is no way of being sure that for fast ortho film GBX-2 will be definitely be suitable. It may or may not be different from a Kodak 2.

What do you make of various statements that GBX-2 is OK?

It was just that Jimi3 seems to be on the horns of a dilemma about GBX-2 and my question to you and your answer might help him but I accept that in some cases you can't always give a definite answer and this looks like one of them

pentaxuser

I have no conclusion.
I merely posted the information available to me.
And observed that the information about the applicability of one type of safelight filter for other types of applications would not likely come from Eastman Kodak.

 

[juan]

I use GBX2 for my X-Ray film. To my eye, it is much brighter than a normal red filter. I'd say there's a good chance its the source of your fog. Test.

 

[Jimi3]

I guess I’ll have to retest the safelight. In the meantime, I did order a no.2 Kodak filter.

 

[Vaughn]

Depending on your pocketbook, nerdiness, and love of stuff, you might consider IR goggles and an IR light source to work with.

Even with the Dark Red filter, Ilford still recommends 15W, a minimum of 4 feet away, and less time as possible. Good luck!

 

[Jimi3]

Depending on your pocketbook, nerdiness, and love of stuff, you might consider IR goggles and an IR light source to work with.

Even with the Dark Red filter, Ilford still recommends 15W, a minimum of 4 feet away, and less time as possible. Good luck!

Interesting. How much do you think I’d have to spend to get a setup like that?

 

[Vaughn]

Using the Forum's search, this is one of the discussions I found;

Sold - Night Vision scope ATN Viper

Night Vision scope ATN Viper. I used this for development by inspection and it worked great. Tested and it works also the IR source. Here is a link to the product: https://www.midwayusa.com/product/1008673597 Price is $125 or BO plus shipping to your location. I will only ship to US. Includes an...

www.photrio.com

There were quite a few other posts on the subject, but I have never perused them.

 

[juan]

There's also a lot of discussion about the Viper producing enough visible light to fog film.