Split grade printing clarifications...?

Hello everyone!
I want to try the split grade printing technique, but first i want to fully understand how to and how it works. Please be patient and correct my mistakes and misunderstandings.
First of all, I have to do a test strip with n° 0 filter (approx 1/2 of the correct time needed for normal exposure), and when i find the detail I want in the highlights, i take note of the newfound time.
I then proceed to do the same on the same strip used for the highlights, but with a n°5 filter. I want to look for the detail in the shadows and then I need to write down this second time also. Finally, printing with the highlights time with the first filter, then switching it with the higher one and then printing for the shadows time
Now my questions are:
1) What happens in the final print if I vary (increasing and decreasing) the 0 and 5 filters used, respectively, for the highlight and for the shadows?
2) If I feel that I might have to burn/dodge, in which moment should I do it? During the highlights phase? During the shadows one? what changes between those two moments?
3) Except finding the exact contrast for the scene, this particular procedure what might also be useful for? Might help in those situations when there are too many zones to burn/dodge? How?
I know there are many questions, but on my books i've still not found a satisfying answer. Thanks in advance to whom want to respond.

After you determine the exposure for the 0 (or 00) filter, you expose the second strip for that time. Then, on that same strip, you make a number of exposures with the 5 filter to determine the final exposure for that filter, so it is not just the 5, but the combination of 0 & 5. You would burn and dodge depending on the tone of the areas needing them--for example, burins the corners with the 5 filter to darken overall, burning with the 00 filter to bring more detail to lighter areas. Same for dodging.

Pieter12 said:

After you determine the exposure for the 0 (or 00) filter, you expose the second strip for that time. Then, on that same strip, you make a number of exposures with the 5 filter to determine the final exposure for that filter, so it is not just the 5, but the combination of 0 & 5. You would burn and dodge depending on the tone of the areas needing them--for example, burins the corners with the 5 filter to darken overall, burning with the 00 filter to bring more detail to lighter areas. Same for dodging.

Click to expand...

Yes.

See also: https://www.lesmcleanphotography.com/articles.php?page=full&article=21

Pieter12 said:

You would burn and dodge depending on the tone of the areas needing them--for example, burins the corners with the 5 filter to darken overall, burning with the 00 filter to bring more detail to lighter areas. Same for dodging.

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Actually there may be reason to so the opposite. In some ways burning with a number 5 filter increases contrast and burning the corners may leave unsettling highlights untouched. Also bringing out detail in lighter areas may require a number 5 filter to increase contrast and avoid greying of the overall area.
Way Beyond Monochrome by Ralph Lambrecht (Author), Chris Woodhouse (Author) demonstrate this. it did take me a while to believe this, but it is true. In some ways use of 5 and 00 is bet to be thought of increasing and decreasing contrast in highlights and shadows, although of course either effects the other.

cowanw said:

Actually there may be reason to so the opposite. In some ways burning with a number 5 filter increases contrast and burning the corners may leave unsettling highlights untouched. Also bringing out detail in lighter areas may require a number 5 filter to increase contrast and avoid greying of the overall area.
Way Beyond Monochrome by Ralph Lambrecht (Author), Chris Woodhouse (Author) demonstrate this. it did take me a while to believe this, but it is true. In some ways use of 5 and 00 is bet to be thought of increasing and decreasing contrast in highlights and shadows, although of course either effects the other.

Click to expand...

Obviously, burning and dodging depend on the image. I often both burn or dodge areas with both filters, for different times, to get the effect I want. That's what's nice about split-grade printing, it gives you many options.

I tend to use a hybrid approach: I find the filtration I need for the overall base exposure (I use a color head). Then, if I need burning at a different setting, I'll change filtration for that. For the rare cases when I need to dodge with a low-contrast setting, I'll use this setting as my base exposure and then burn overall with the higher contrast setting later. This works well for me and I don't have to make so many test strips.

Keep in mind that the benefits of split-contrast printing only happen when separate areas of the print need different contrast settings. You only really need to change contrast for burning if you start with the lowest needed contrast for your base exposure.

Example: let's say I've got an area that needs a lot of low-contrast exposure: I'll find a base exposure with the needed low-contrast setting, find the time I need for the first overall base exposure and then burn the area in question more at that low-contrast setting. Then, I'll change to the higher-contrast setting and give the exposure I need to get the contrast I want. I'll then dodge the area I've already burned in a bit as needed to keep contrast from building up too much there.

The possibilities are myriad.

Doremus

Pieter12 said:

Obviously, burning and dodging depend on the image. I often both burn or dodge areas with both filters, for different times, to get the effect I want. That's what's nice about split-grade printing, it gives you many options.

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Mmmhh so in which cases you burn and dodge with each filter in the different phases? What are the variables and what controls what?

Still, what happens if I vary the filter grade during printing? I.e. using a 1,5 filter instead a 00 and a 3,5 instead of a 5?

A practical solution that has worked for me for 30 years is to expose using a mixed filter that passes a controlled amount of green and blue light. During exposure, hold back areas with dodging tools and after exposure burn areas in neeed with white light.

Thrain said:

Mmmhh so in which cases you burn and dodge with each filter in the different phases? What are the variables and what controls what?

Still, what happens if I vary the filter grade during printing? I.e. using a 1,5 filter instead a 00 and a 3,5 instead of a 5?

Click to expand...

I only use 00 & 5 filters. I can usually judge from the test strips that I have made how much additional (or less) exposure of each filter I will need to get the tones I want in areas that need dodging or burning.
Fortunately, I keep notes on all my work prints. Not necessarily the best example, there wasn't a lot of doging/burning, but for this one, this is what I did:
I use an ND filter in the filter drawer to lengthen exposure time to make dodging and burning easier.
00 filter: 11.9 sec. + burn truck 1 stop (11.9 sec)
5 filter: 28.5 sec., dodge bushes 1/4 stop (7 sec.) + burn sky 1/2 stop (14+ sec),

This is a scan of the 8x10 work print. The final is a 10x10 image on 11x14 Ilford MG classic gloss fiber base paper.