DDoug Posted March 24, 2017 Share Posted March 24, 2017 With continuous lights, it's possible to run into a problem with insufficient CRI (color rendering index). Quartz-halide lamps have a relatively high CRI, but they tend to run too hot to be practical in a softbox. CFL and LED lamps might be okay, but many of them are not, especially cheaper ones*. The problem with low CRI is that, even when you've balanced color using a Kodak gray card or similar, correct color will be impossible to achieve because the spectrum of the light has gaps in it (or however a more knowledgeable person would describe it). CFL lamps, including those sold by photographic supply houses, often have CRIs as low as 80 or even lower, whereas strobes and quartz lights usually are 95 or better. Light from the sun, the standard by which artificial light sources are measured, is 100. An informative discussion of CRI is here: https://petapixel.com/2013/09/19/importance-choosing-high-quality-cfl-bulbs-continuous-light-shooting/ * edit: Some of the recent versions of LED studio lights have a high CRI and are worth looking at. Link to comment Share on other sites More sharing options...
Roman78 Posted March 27, 2017 Author Share Posted March 27, 2017 Yes i read that. Also that this kind of light makes people look a little ill. But the good thing of old Computer is, look at 5 same machines, they all have a different colour. The problem that occurs is that some pictures looks shaky because of a too long exposure time. Even 1/60 on a tripod looks shaky. Didn't had this problem whit the flash lights. I have to use 1/100 and a little higher ISO. My DSLR does not have MLU. Link to comment Share on other sites More sharing options...
John Richmond Posted March 27, 2017 Share Posted March 27, 2017 Yes i read that. Also that this kind of light makes people look a little ill. But the good thing of old Computer is, look at 5 same machines, they all have a different colour. The problem that occurs is that some pictures looks shaky because of a too long exposure time. Even 1/60 on a tripod looks shaky. Didn't had this problem whit the flash lights. I have to use 1/100 and a little higher ISO. My DSLR does not have MLU. Live view if you've got it combined with a remote release or use the built in timer to minimise operator induced shake. Link to comment Share on other sites More sharing options...
Roman78 Posted March 27, 2017 Author Share Posted March 27, 2017 Yes i read that. Also that this kind of light makes people look a little ill. But the good thing of old Computer is, look at 5 same machines, they all have a different colour. The problem that occurs is that some pictures looks shaky because of a too long exposure time. Even 1/60 on a tripod looks shaky. Didn't had this problem whit the flash lights. I have to use 1/100 and a little higher ISO. My DSLR does not have MLU. Live view if you've got it combined with a remote release or use the built in timer to minimise operator induced shake. I noticed when i shoot in Silence Mode I have less shake. I think it is the mirror. Live View is something i should test indeed. Link to comment Share on other sites More sharing options...
DDoug Posted March 27, 2017 Share Posted March 27, 2017 I've been going back and forth about this question, whether to replace my CFL light with electronic flash or one of the recently available high-CRI iterations of LEDs. The latter are cheaper by far. I have a mirrorless camera and a cable release, so there's no worry about camera shake, but subject movement (e.g., pouring liquid) might require flash unless the LED light were so strong that a high shutter speed could be used. I used to have 2000 Ws unit and finally replaced it with 4000 Ws. It wasn't overkill, considering the needs of 4x5 camera and slow film. With a digital camera and higher usable ISOs, though, less is required but exactly how much less I don't know. Paul C. Buff publishes a light output table for his strobes. It looks like for tabletop, a 600 Ws strobe in a softbox would be enough. Cheers, Don edit: "But the good thing of old Computer is, look at 5 same machines, they all have a different colour." CRI problems also can show up as strange hues and casts in neutral, especially reflective, surfaces such as chrome. Link to comment Share on other sites More sharing options...
wiskerke Posted March 27, 2017 Share Posted March 27, 2017 edit: "But the good thing of old Computer is, look at 5 same machines, they all have a different colour." CRI problems also can show up as strange hues and casts in neutral, especially reflective, surfaces such as chrome. Try photographing meat in a butcher shop. Or tulips in a exhibition hall that normally is the village gymnasium. Creating a camera profile helps a lot. Unless there are real holes in the spectrum. Like with yellow sodium vapor lights or cheap fluorescent tubes. You do need to have a ColorChecker or ColorChecker Passport for that. ColorChecker Passport comes with it's own Lightroom plug-in. The Adobe DNG profile editor is standalone. wim Link to comment Share on other sites More sharing options...
Phil Robinson Posted March 27, 2017 Share Posted March 27, 2017 My 'studio' is a table made from clear perspex with a studio flash underneath. I can the put a sheet of paper / frosted glass / white perspex on top and get an instant soft light as big as I want. Link to comment Share on other sites More sharing options...
Roman78 Posted March 30, 2017 Author Share Posted March 30, 2017 I made something like that from an old TFT screen (see previous page), but did not tried something like colour or frosted paper on it. Could be a nice effect, will try that sometime. So.. yesterday I had some time to edit pictures I took last week. Now I need to practise my scratch-removing-skills. The program I normally use is DxO Optics Pro 9, but that has no good scratch removing options, so I have to export some pictures into another photo editing software. Link to comment Share on other sites More sharing options...
Roman78 Posted April 22, 2017 Author Share Posted April 22, 2017 Had not much time lately, but I edited my first uploaded pictures (brighter and more contrast) now I had some time to shoot some more Product Pictures. Small objects are not the problem, but bigger are. On small object I just can adjust the tone curve a little and I get a nice picture, like this nice calculator. But bigger machines are a bit of a problem, like this Apple II. Here I did a Cut-out rather than a tone curve modification only. Good is that it has straight lines. Did not add shadows on this one. What do you guys think. Link to comment Share on other sites More sharing options...
Roman78 Posted April 26, 2017 Author Share Posted April 26, 2017 Yeah.. my first 5 test images are on-line... Link to comment Share on other sites More sharing options...
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