Delta 100 more dense than TMX100

[Kilgallb]

I was out of TMX100 and the camera shop had DELTA 100. The ilford site suggested D76 stock 7 minutes with a speed rating of EI50. I exposed a sheet of TMX 100 and a Sheet of delta 100 on the same scene and found the Delta 100 to be at least 2 stops more dense. I also develop TMX 100 at 7 minutes in a roller drum (4x5).

Is this normal for delta to apparently have a higher speed than TMX? Or is my development time just too high?

 

[K-G]

I have never used D-76 for Delta 100 but I have found the Ilford recommendation for DD-X ( 12 min at 20 deg C ) to be far to long.
9.5 - 10 min seems to give much better results. I suspect that this relation also can be valid for other developer recommendations.

Karl-Gustaf

 

[Ian Grant]

I think your problem is the recommended 7 mins is for normal agitation not continuous rotary agitation. My experience is that Delta 100 is a bit faster than Tmax 100 so it's a case of slight over development and over-exposure.

It's a good idea to do a test to determine the best EI and development time for each film & developer.

Ian

 

[Ricardo Miranda]

I was out of TMX100 and the camera shop had DELTA 100. The ilford site suggested D76 stock 7 minutes with a speed rating of EI50. I exposed a sheet of TMX 100 and a Sheet of delta 100 on the same scene and found the Delta 100 to be at least 2 stops more dense. I also develop TMX 100 at 7 minutes in a roller drum (4x5).

Is this normal for delta to apparently have a higher speed than TMX? Or is my development time just too high?

As Ian said above, if you use continuous agitation, Ilford recommends to reduce development times by up to 15%.
You might want to read the Delta 100 datasheet again:

Where continuous agitation is used for manual processing (as in a dish/tray or with some types of developing tank), reduce these times by up to 15%. For use in rotary processors without a pre-rinse, reduce the spiral tank development times by up to 15%. A pre-rinse is
not recommended as it can lead to uneven processing.

Enjoy the film!

 

[Richard S. (rich815)]

I reduce my development times by 30% from suggested times when doing continuous agitation. But that's me for my purposes of what I do with my negatives. I think it's why you got such dense Delta 100 though.

 

[Jim Noel]

I was out of TMX100 and the camera shop had DELTA 100. The ilford site suggested D76 stock 7 minutes with a speed rating of EI50. I exposed a sheet of TMX 100 and a Sheet of delta 100 on the same scene and found the Delta 100 to be at least 2 stops more dense. I also develop TMX 100 at 7 minutes in a roller drum (4x5).

Is this normal for delta to apparently have a higher speed than TMX? Or is my development time just too high?

Yes! When I use it I use an EI of 100 with D-76 straight, or an EI of 80 with D-76 1+1.

 

[Kilgallb]

Thanks everyone. I adjusted my development time down 15% on the backup exposures and now the density is near normal. I will do a speed test on the weekend.

 

[pgomena]

I've found Delta 100 gains in density much faster than other films. I usually end up either diluting the developer or cutting the time. When you hit it spot-on, it's great film.

 

[Richard S. (rich815)]

I've found Delta 100 gains in density much faster than other films. I usually end up either diluting the developer or cutting the time. When you hit it spot-on, it's great film.

The t-grain films have always been sort of notorious for being less forgiving than classic emulsions like Tri-X, HP5+, Plus-X and FP4+...

 

[pgomena]

Yes, and I've found the Delta 100 to be least forgiving of all. Still, it's great film and I'm probably more to blame than the film is.

 

[Harman Tech Service]

Ian and Ricardo have done a wonderful job of answering this query. See our Film processing chart at www.ilfordphoto.com/Webfiles/2015416153431192.pdf - particularly the notes at the bottom.
Incidentally, you will also see that the dev. times for Delta 100 in DDX have been reduced due to retesting following customer feedback.
This will soon be updated on our other fact sheets and then on our packaging as it is replaced.

Regards,
David

 

[JW PHOTO]

Ian and Ricardo have done a wonderful job of answering this query. See our Film processing chart at www.ilfordphoto.com/Webfiles/2015416153431192.pdf - particularly the notes at the bottom.
Incidentally, you will also see that the dev. times for Delta 100 in DDX have been reduced due to retesting following customer feedback.
This will soon be updated on our other fact sheets and then on our packaging as it is replaced.

Regards,
David

David,
I'm glad you are here as it always helps to have questions answered directly and straight from the horses mouth, so to speak. My hat is off to Harman! Many manufactures do not understand how important a line of communication really, really is and they usually pay for not having it. Keep that line of communication open and it always pays off. Thanks for being here.......................JohnW