Thanks for another great video Jim! This makes so much sense and when I pluck up the courage to develop my own film, I certainly will be using this method to measure. Just wondering if there is a developer that works at room temperature and does not require heating and brining up to temperature, if there is something out there that does this then I will certainly have the courage to develop my own.
Hi Cerita, most b/w developers are made to work at 20 deg C which is typical room temp. If your developer is a bit warmer or cooler, you can warm it by sitting the container in a bath of warm water or cool it via the opposite. Alternatively you can also adjust the developing time to accommodate a different developer temperature. There is a web site www.digitaltruth.com/devchart.php that gives you the developing times for any film / developer combination. There is also a section called Temp/Time convertor where it will adjust the time accurately for a different temperature. Its actually very simple. When you are ready to try this, I’m happy to sit with you through your first roll via Zoom. Let me know if I can help in any way.
Does this really work for all types of chemistry? The scale is obviously measuring the liquid by weight, not volume. Unless it has a way to enter the specific gravity of the liquid, I don't see how it can accurately measure volume. If you are just saying that the volume (in mL) is equal the the scale's reading (in grams), then doesn't that only work for liquids like water, there the specific gravity is 1.0? For other liquids, there is bound to be an error. For example, Kodak HC110 has a specific gravity of 1.24 (according to the MSDS), so using the scale's grams reading would cause a volume error of 20% or so. Maybe most chems are close enough to 1.0 that it doesn't matter. But somehow, in principle, it seems wrong to use a scale to measure volume. Am I missing the point, somehow?
Most developers are in very small quantity compared to water. In the example I was using 30ml of developer with 270 ml water. The difference you are talking about is so incredibly slight it will have absolutely no effect. As I did say in the video, this is not accurate enough for scientific purposes but it is more than sufficiently accurate for black and white darkroom chemistry. If you are doing large volumes of straight developer or high concentrations, my suggestion is to try it to see how it works. In your example HP5 in HC110 at 1:31 means 10ml developer with 270ml water so even with the SG difference you might be off by a little over one ml, which will make absolutely no difference. I’ve been doing darkroom work for almost 50 years and I teach film photography, it has always worked for me.
Thanks for another great video Jim! This makes so much sense and when I pluck up the courage to develop my own film, I certainly will be using this method to measure. Just wondering if there is a developer that works at room temperature and does not require heating and brining up to temperature, if there is something out there that does this then I will certainly have the courage to develop my own.
Hi Cerita, most b/w developers are made to work at 20 deg C which is typical room temp. If your developer is a bit warmer or cooler, you can warm it by sitting the container in a bath of warm water or cool it via the opposite. Alternatively you can also adjust the developing time to accommodate a different developer temperature. There is a web site www.digitaltruth.com/devchart.php that gives you the developing times for any film / developer combination. There is also a section called Temp/Time convertor where it will adjust the time accurately for a different temperature. Its actually very simple. When you are ready to try this, I’m happy to sit with you through your first roll via Zoom. Let me know if I can help in any way.
@@jsollowsphotography Thanks so much Jim! A very kind offer, I really appreciate it and will find the courage to do this soon.
Also, 1ml of water = 1g. So measuring water volume at least is simple. 100ml = 100g, etc.
Thank you for this. I'm updating the video to reflect this information.
CZcams won't allow me to replace the video so I've added your information into the show notes. Thanks again!
Great Idea! We'll order one and use it in our new "Kentucky Darkroom" We are looking for ways to make it great.
Hey that sounds interesting! Tell me more about the Kentucky Darkroom?
Does this really work for all types of chemistry? The scale is obviously measuring the liquid by weight, not volume. Unless it has a way to enter the specific gravity of the liquid, I don't see how it can accurately measure volume. If you are just saying that the volume (in mL) is equal the the scale's reading (in grams), then doesn't that only work for liquids like water, there the specific gravity is 1.0? For other liquids, there is bound to be an error. For example, Kodak HC110 has a specific gravity of 1.24 (according to the MSDS), so using the scale's grams reading would cause a volume error of 20% or so.
Maybe most chems are close enough to 1.0 that it doesn't matter. But somehow, in principle, it seems wrong to use a scale to measure volume. Am I missing the point, somehow?
Most developers are in very small quantity compared to water. In the example I was using 30ml of developer with 270 ml water. The difference you are talking about is so incredibly slight it will have absolutely no effect. As I did say in the video, this is not accurate enough for scientific purposes but it is more than sufficiently accurate for black and white darkroom chemistry. If you are doing large volumes of straight developer or high concentrations, my suggestion is to try it to see how it works. In your example HP5 in HC110 at 1:31 means 10ml developer with 270ml water so even with the SG difference you might be off by a little over one ml, which will make absolutely no difference. I’ve been doing darkroom work for almost 50 years and I teach film photography, it has always worked for me.
@@jsollowsphotography In this case, you don't need a scale that can measure ml, because it's using the same magnitude as grams...