So just how much compensation do I need with CC40Y filter?

[eric]

So I didn't realize the Beseler I got a while ago had the old W45 bulb. I've got another one and opened it and it was W45 as well (this I knew but just wanted to see what the old one was).
Well, anyway, I'll get some CC40Y filters cause I can't afford 250 bucks for 2 new bulbs.

I'm thinking this will be like camera exposure. About 2 stops? So a 10 second exposure increase to 20 seconds?

 

[Claire Senft]

The density of .40 indicates approx. 1 1/3 stop. However the material you are printing on will I would think determine the compensation needed. I can think of nothing better than a couple of test strips. 1 test strip with the 40y 1 test strip w/o the yellow filter. I would expect that on graded paper the 40y would do anything except to make your exposure longer.

 

[ic-racer]

So I didn't realize the Beseler I got a while ago had the old W45 bulb. I've got another one and opened it and it was W45 as well (this I knew but just wanted to see what the old one was).
Well, anyway, I'll get some CC40Y filters cause I can't afford 250 bucks for 2 new bulbs.

I'm thinking this will be like camera exposure. About 2 stops? So a 10 second exposure increase to 20 seconds?

Difficult to know for sure, because, as you know the yellow will only effect the green sensitive emulsion. I'd just do some test strips with a negative known to print OK and see. You don't really need to compensate for the filter, unless you are trying to compare times with prints already made without the filter.

BTW, I have had good luck with two filter (split grade or what ever you want to call it) printing with the W45 without needing the yellow. I'm anxious to see how the yellow filter works for you, as I want to expand to a full filter set (and added yellow) to add flexibility to my setup.

 

[eric]

Okay folks, just got out of the darkroom with the CC40Y installed. I placed it inside the bottom bellows of my Beseler so its sitting on top of the lens. I've done QA work before for software company so I can take out most of the variables. WITH the CC40Y filter, the same negative and time, the print looked about 1 - 1.5 stops LIGHTER. That was expected. I used a #3 filter. Usually I get pretty good prints with the type of processing I do. I've had this enlarger for about a year now but haven't been in there for more than....hmmm 40 hours the whole year.

So I increased my exposure time to about 1.5 stops and it was a little dark. So I backed down to 1/2 stop less thereby making the exposure 1 stop more than the original and did a little edge burning. That print looked just about the same exposure as the first BUT..... the contrast is WAYYYYYYYYY BETTER! So I figure, the filter will add at least 1 stop more exposure but not as much as 1.5 stops.

I was wondering if I lost my printing touch with this new enlarger. Seems that the darker areas needed more burning in than I was used to. I also couldn't get that right contrast like I do when I scan the negative and play around in it in GIMP. I always thought "why can't I get this same contrast when I actually print?" Everything else was the same processing-wise for years!

The bad part is...1 stop or 1.2 stops more than my usual is pretty long. And if I need to print a large print, whew! That's gonna be a loooong exposure time! Dang, I really may just bite the bullet and get a V54 bulb.

But wow, neatO experiment!

Thanks EVERYBUDDY!

 

[ic-racer]

Thanks for posting your results!

 

[eric]

The density of .40 indicates approx. 1 1/3 stop.

This was right on the money. I'm using an F-stop timer so its easy to plug in +1 stop more. So that is about the range...1 stop to 1.33 stops.
Thanks Claire.

 

[Claire Senft]

ubwelcome.