Kodak D-76 8x10 in Expert drum

[ic-racer]

@IC-racer but I want to process 4 sheets at the same time in 1l at 1:1

Wanting and doing are not the same
Seriously, I believe many issues with uneven development (uneven sky etc.) are from developer exhaustion. What I do is err on the side of 20% to 50% capacity safety factor. Tmax developer is 50 to 60 cents per sheet if only used to about 50% capacity, whereas the T-Max film cost $10 per sheet.

[Jim Noel]

@IC-racer but I want to process 4 sheets at the same time in 1l at 1:1

The developer is going to exhaust at a faster rate because of the 4x larger surface area. Once exhausted, no further development will occur. That's what "exhaustiion" means.
I suggest you try 2 sheets with a 10% increase in time and check the result. if you are satisfied , try 3 sheets. I believe you will see severe underdevelopment by this time.
In other words, I don't believe you can put enough 1+1 developer in the tank to develop 4 sheets of 8x10.
If you attempt to put more than 1.5 liters of developer in the tank it gets to the point of overflowing, and run the risk of overloading the motor.

[Vaughn]

Develop in two runs of developer. Figure the total amount of developer needed and use half of the developer for half the time and then dump and refill with second half and finish developing.

I've done it with 5x7s in a 3006.

[PengNuo]

Wanting and doing are not the same
Seriously, I believe many issues with uneven development (uneven sky etc.) are from developer exhaustion. What I do is err on the side of 20% to 50% capacity safety factor. Tmax developer is 50 to 60 cents per sheet if only used to about 50% capacity, whereas the T-Max film cost $10 per sheet.

Fair enough. A pack of D-76 is 88¥ here which is roughly 13$. At 16 sheets capacity it doesnt really break the bank. Luckily GP3 is still rather cheap here at 2$/sheet of 8x10.

[PengNuo]

Develop in two runs of developer. Figure the total amount of developer needed and use half of the developer for half the time and then dump and refill with second half and finish developing.

I've done it with 5x7s in a 3006.

Interesting!

[Hugo Zhang]

I use Jobo 3005 with D76 at 1:1 all the time. 800ml for four sheets of 8x10 is not a problem at all.

[PengNuo]

I use Jobo 3005 with D76 at 1:1 all the time. 800ml for four sheets of 8x10 is not a problem at all.

😂 ok so back to square one.

[Martin Aislabie]

I put 750cc of developer + water solution in my CPP with no problems at all.

I have tried experimenting with developer quantity and could measure no perceivable difference in motor tone or measured speed as the volume increased.

I do however use the rollers for an Expert Drum - they are lower friction with metal bearings.

They are listed in the spares section of your instruction manual.

Martin