Push Processing

[Digital Matt]

I made a goof today, while shooting a project. I was helping my wife shoot her project last night, and she was using Ilford Delta 400, so I had my meter set to ISO 400. I got up early this morning to tackle mine, and forgot to reset the meter to 100, as I'm using Ilford Delta 100.

According to Ilford, this film will give excellent results if rated at ISO 50,100, or 200. I need to push to 400.

My questions are, what is the likelihood that the negatives will turn out ok? (if added grain is the only result, that's fine)

How would I calculate the development time, since Ilford doesn't recommend pushing to 400, and doesn't have any info for dev time?

Thanks gurus

p.s. Dev times for D-76 1:1 are 9 1/2, 12, and 14 respectively. Would 16, or 16 1/2 be a good guess?

 

[terri]

Tricky one, Matt.

First off....that's a very common mistake to make, and now that you've made it, you'll probably be very good about checking that ISO from now on.

Secondly, I would say.....don't use D-76. I would highly recommend trying TMax developer, because the stuff really is designed for push processing. There is still no info for Delta 100 pushed to 400, because as you've learned....it's not recommended. So there is a chance you just aren't going to get much.

If it were me (and better minds may weigh in with something better than this) I would use TMax developer, 1:4. Use distilled water for the dilution, and don't bother trying to cool it to 20C/68 degrees - leave it at room temp. The warmth might be your friend here.

I'd go as long as 12 minutes developing time, maybe a bit longer....and agitate 3-4 times every 30 seconds after continuous agitation the first 30 seconds as usual. Stop, fix, hypoclear as usual.....and see what you get.

I'd like to see someone else's suggestions, too. It's all about making an educated guess, and I'm not overly edumacated here. This is pure SWAG.

TMax comes in a small plastic bottle and it's a syrupy liquid, extremely easy to mix and use. You should have no trouble finding any, if you want to go this route.

 

[Digital Matt]

Ahh, just who I was hoping would see this

Thank you Terri. Your information is much appreciated. As you said, (hopefully) I probably won't make this mistake again. I can always reshoot. It's just 15 shots on 120, but I thought it might be worth a try to save it with development.

At school we strictly use D-76, so I'll have to buy some Tmax of my own to use, which is no big deal. I haven't set up my home darkoom yet, otherwise I'd just do it here. That actually wouldn't be all that difficult, just for processing film. Maybe I should just do that.

I think I'll shoot another roll though, just in case Thanks again Terri!

 

[terri]

You're welcome.

I'll be curious to see if you get anything. Come back and let us know how it went, ok?

I'm thinking you'll like the Tmax developer, regardless. If you ever decide to try HIE, you can use it for that, too. Keeps a long time on the shelf in that bottle.

Film processing at home is laughably easy, once you find a dark closet to load in.

 

[Solarize]

I dont have any experience with T-max, have always used Ilford's DDX for pushing and higher speed films (haven't gone 100 to 400 mind you). I believe it is designed for the delta range of films and does a good job at softening the grain.

Could have a look on the massive dev chart perhaps.

www.digitaltruth.com/devchart.html

Good luck with it

 

[terri]

Yeah, I love that chart. :thumbup:

Unfortunately, it didn't help us with this particular scenario!

 

[journeyman]

Yeah, I love that chart. :thumbup:

Unfortunately, it didn't help us with this particular scenario!

Au Contraire, I had never seen this sight before but I went to push Processing and I found it extremly helpful for this situation. 400 to 100 is equal to two stops just about. So for the directions multiply the time you ussually use by 2.25.

(Note this is all therotical so it should work)
But I'm just using what I know with information I found no personal expierence here.

 

[Digital Matt]

Thanks for your input everyone I was planning to buy some chemicals and start developing at home. I wanted to use all Ilford chemistry, and since I'm shooting a lot of Ilford Delta films, DD-X sounds good.

I'll let you know what happens

 

[ksmattfish]

You'll get photos. You might lose shadow detail and contrast, but the negs will be printable.

When I'm making blind (meaning no personal film testing) estimates for pushing dev time I add 50% per stop to the manufacturer's recommendation for traditional grain emulsions, and +20% per stop for tabular grain emulsions (Tmax and Delta). Going the other way I use -20% per stop for traditional films, and -10% per stop for tabular grains films.

 

[Digital Matt]

Thanks Matt I went ahead and re-shot the roll, because I needed the shots for a project. They turned out fine, exposing for the correct ISO I will give this bad roll a shot though, just to learn from it.

Thanks again everyone, for all the advice

 

[terri]

I'll be interested to see how they turn out, Matt, and what process you follow for this scenario.

Mr. Needham! :sun: How lovely to see you. Hope your summer is good.

 

[mysteryscribe]

Im trying to kick the asa up on some paper negs... without much success I wonder if that formula would work for it..

 

[ksmattfish]

Mr. Needham! :sun: How lovely to see you. Hope your summer is good.

Been very busy, hooray! I'm finally caught up from the early summer weddings, and I've got a few weeks of the dog days of summer before the late summer/fall weddings start. I finally had some time to visit TPF. I like the new look and organization.

 

[terri]

I finally had some time to visit TPF. I like the new look and organization.

Thank you! I'm so happy to hear that. Busy members like yourself who "swing both ways" were what we had in mind when developing the new layout. The goal was easier navigation "at a glance".

Stick around, there are more fun things coming down the pipe!