Streaking with Richeson 9010 Magic Brush

[donbga]

Hi Everyone,

I'm occasionally getting streaking when coating with a magic brush and don't understand why. Does anyone have any tips to share?

Thanks,

Don Bryant

[Jorge]

Hi Everyone,

I'm occasionally getting streaking when coating with a magic brush and don't understand why. Does anyone have any tips to share?

Thanks,

Don Bryant

The brush is either too dry or too wet. I have had this happen to me in both instances. Specially when the brush is too dry and the climate is dry too. Happen to me with 3 12x20...you probably heard the cussing...

[sanking]

Hi Everyone,

I'm occasionally getting streaking when coating with a magic brush and don't understand why. Does anyone have any tips to share?

Thanks,

Don Bryant

Don,

Has this been going on for very long? If it is of recent origin I suspect that the unusually cold weather and low humidity we are experiencing in the southeast at this time may have something to do with the streaking.

I rarely experience streaking when coating with the Richeson but it is hard to describe the technique of coating. First, make sure that you use enough solution to go over the print from side to side, up and down and on the diagonal before the sensitizer starts to dry. And, use very light brush strokes as you complete the coating. The few times that I have seen streakiing the most probable causes were, 1) beginning to coat with an insufficient amount of sensitizer, and 2) using heavy brush strokes at the end of coating when the sensitizer had begun to dry.

And of course, start coating with the brush neither too wet nor too dry. What I learned from Kerik Kouklis about coating with the Richesoin was, first wet the brush and then shake out the excess moisture, but not so much that the hairs of the brush separate.

Sandy

[donbga]

The brush is either too dry or too wet. I have had this happen to me in both instances. Specially when the brush is too dry and the climate is dry too. Happen to me with 3 12x20...you probably heard the cussing...

Jorge,

Yeah I heard you Perhaps you heard me!

I've tried to make sure that I've pre-wet the brush, perhaps it is just a little too wet.

Thanks,

Don

[donbga]

Don,

Has this been going on for very long? If it is of recent origin I suspect that the unusually cold weather and low humidity we are experiencing in the southeast at this time may have something to do with the streaking.

I rarely experience streaking when coating with the Richeson but it is hard to describe the technique of coating. First, make sure that you use enough solution to go over the print from side to side, up and down and on the diagonal before the sensitizer starts to dry. And, use very light brush strokes as you complete the coating. The few times that I have seen streakiing the most probable causes were, 1) beginning to coat with an insufficient amount of sensitizer, and 2) using heavy brush strokes at the end of coating when the sensitizer had begun to dry.

And of course, start coating with the brush neither too wet nor too dry. What I learned from Kerik Kouklis about coating with the Richesoin was, first wet the brush and then shake out the excess moisture, but not so much that the hairs of the brush separate.

Sandy

Sandy,

I thought the low humidity might be the culprit although I humidfy my darkroom and try to keep it above 50%. I'm thinking that I may be stroking the paper a little to heavily as you mention.

Thanks,

Don

[rbarker]

Don - when I read your subject in the index, I was afraid you had been arrested. But streaked prints might be almost as bad, I guess.

[Mateo]

Here two bits from a rookie for what it's worth.
The humidity of the room is not the only thing I worry about. If it's been dry for a while my paper is too dry even if I humidify the room. After the weather has been a couple of days over 60% Rh, then it's ready to go. I guess you could store your paper in a humidity controled cabinet but that's not practical for me so I just wait for the weather to get better. When I use the Fabriano paper and presoak in oxalic, I can print in dry weather by just catching the paper at the right point of drying.

[photomc]

From another rookie, that just started using the 9010 - it's all new to me - have noticed the same results as Mateo. If the humidity has been low (as in <50%) and temp is cold (meaning the heat is running) the paper seems to need a little more humidity. Just set up a humidifer, so can't comment on results from that yet. You would think preping paper for 4x5 would be a snap, but not always. Does anyone know of a way to measure the mositure in the paper? Thought about finding that, because as Mateo stated, when you catch the paper at the right point in drying it seems to work great.

[Michael Mutmansky]

Are you single coating or double coating?

If you are single coating, then I would suggest you also consider how much solution you are using, in combination with the humidity in the paper and moisture in the brush. If the paper is especially dry, it will soak up the solution fast, and you may end up not having enough to properly cover the image area.

When I coat, the paper is very wet when I am finished, evenly coated, but wet, so there is some soaking and drying to be done by the paper.

Before starting, I dip the brush in H2O so that it is soaked, and then shake it out (hard) about four times onto the ground next to the coating table. That seems to work very well.

One more thing; I coat with the brush in both directions, left to right and back, and also up to down and back, all on the same sheet of paper. As long as you have enough solution, that should pretty much eliminate any streaking.

These comments apply to Platine and Cot320. Other papers may require a different procedure depending on their absorption characteristics.


---Michael

[donbga]

Are you single coating or double coating?

If you are single coating, then I would suggest you also consider how much solution you are using, in combination with the humidity in the paper and moisture in the brush. If the paper is especially dry, it will soak up the solution fast, and you may end up not having enough to properly cover the image area.

When I coat, the paper is very wet when I am finished, evenly coated, but wet, so there is some soaking and drying to be done by the paper.

Before starting, I dip the brush in H2O so that it is soaked, and then shake it out (hard) about four times onto the ground next to the coating table. That seems to work very well.

One more thing; I coat with the brush in both directions, left to right and back, and also up to down and back, all on the same sheet of paper. As long as you have enough solution, that should pretty much eliminate any streaking.

These comments apply to Platine and Cot320. Other papers may require a different procedure depending on their absorption characteristics.
---Michael

Hi Michael,

I'm using Stonehenge White and Fabriano Satinata this time around. Do you wet the brush with water before each print?

I coated in both directions left to right and then top to bottom.

Question: How are you initially dispersing the sensitizer on the paper? When brush coating I normally pour the sensitizer onto the center of the paper. I seem to be getting more sensitizer on the "top" half of the paper, suggesting that my technique is flawed. And I am double coating, BTW.

The paper does appear to be very wet when I've finished coating and does appear to look evenly coated, I'm also adding a couple of drops of Everclear per ML of sensitizer. Do you try to overlap the brush strokes?

Thanks,

Don Bryant