|
|||||||||
|
Thread Tools | Search this Thread |
April 9th, 2007, 08:48 PM | #31 | |
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
|
Quote:
Another thing on your comments about the 200w light. It's also a truth that the ballasts in these self-ballasted lights aren't as efficient as fixtures like the CL-455, and others that have separate ballasts. Those ballasts that are chosen with the criteria for all the things we appreciate in video production are hard to rival for quality, efficiency, etc. The spec known as "power factor" in any ballast tells the real story. You want as high a number approaching 1 as possible -- where 1 is perfect. It describes how much of the theoretical output you really reach when operating. Our ballasts are somewhere in the range of .95 to .98. The ballast on the typical 200w light is more in the .8 range so it's wattage output is not as efficient as one of the CL-455 ballasts. You just can't fit that sophisticated of circuitry in such a small package as that required by these self-ballasted lights. |
|
April 9th, 2007, 08:59 PM | #32 |
Trustee
|
update
I did some further testing with the HC1, and have better results with a classic three light setup (key, fill and back or edge). I did this over my lunch break, so if you see gear in the scene, etc. I wasn't too concerned. My only goal: to get a clean, noise-free image with minimal lighting.
The trick? Well, as Marcus indicated, just add more light. Only, I went over-board initially. Too much. Taking a redo, I only needed one extra 23watt CLF to the key, thus using two 23watt CFLs to equal a single 200watt tungsten output (Duh! Don't know what I was thinking, or not). Anyway, that did the trick, I was able to use F2, and 0dB for a noise free image that would pass muster. Here's a link to my flickr site, and the slide slow for 1/60sec shutter: http://www.flickr.com/photos/4537894...60424743/show/ and for 1/30sec shutter: http://www.flickr.com/photos/4537894...60585748/show/
__________________
Pete Ferling http://ferling.net It's never a mistake if you learn something new from it. ------------------------------------------- |
April 10th, 2007, 01:30 AM | #33 |
Trustee
Join Date: Nov 2005
Location: Honolulu, HI
Posts: 1,961
|
Peter, I agree that your current rig does the job. Personally, I would want more light so that a bit of zooming would be possible. It looks like the amount of light you have is just on the edge of workability for the HC1. The shots that looked good were 1/60 f1.8 6db and 1/30 f1.8 and 0db. Without increasing gain to an unacceptable level, there is almost no leeway in this setup. I might switch to 30-40W bulbs/lamps. Regardless, it does work and it cheap and portable. What is that? A 3-point setup for $50? Really, the only thing I noticed was that the backlight was a bit low and hitting mostly the neck area instead of coming down and hitting the hair and shoulders. I'm thinking you may not be using a light stand and can't get high enough. Get one more 8-ft. stand and you have a nice portable setup that gets the job done for a ridiculously small amount of money and space. A bungee cord or two will strap the stands to your rolling cart.
This is clear proof that CFL works and can be made into a portable kit. It's the brains that count, not the cost of the equipment. Richard, I'm sure you are right about the 200W lamp. I'm thinking I might just take off the diffusion the next time I use it and want more light. The source is so spread out that it's not really that harsh without. I think one factor in favor of keeping the 200W softbox is that it looks more professional than my other lights. |
April 10th, 2007, 01:46 AM | #34 |
Trustee
Join Date: Nov 2005
Location: Honolulu, HI
Posts: 1,961
|
Peter, I think I might know why you feel more light is too much in your setup. You may be running into effects from the inverse square law. Your light may be so close that the side of the talent's face that is closest to the key is getting much more light than the other side. Think of it this way:
Assume you are doing a profile shot of someone and their nose is pointing toward the key light. The tip of their nose is closer to the light than their ears by about 6 inches. If the key light is very close, the nose could be getting twice as much light as the ears from the same light. This will cause a highlight on the nose and the ears to underexpose. Of course, this is not a normal situation, but your real scenario may have the light so close that you are getting highlights on the keylit side of the face too soon. Pull the light a bit farther back and you will get more even exposure across the face. Of course, this requires more light and these open fixtures may spill even more, but you get the idea. |
April 10th, 2007, 03:22 AM | #35 | |
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
|
Quote:
|
|
April 10th, 2007, 08:07 AM | #36 |
Trustee
|
Hey Marcus, I realize I could have used more light and the placed the stands farther away, etc. The backlight was just set on the table as I did this over my lunch break and only had about 15minutes. But that was the challenge, how quickly and cheaply could it be done, and with as little room as possible? (Do understand that I have about five-grand invested in both photo and video light kits, gels, etc. I could easily just spend the usual half-day in perfecting the set).
I'm aware of the back light, I just set it on the table as I was impressed with that particular clamp that would double as a stand. I could have also moved the key around another 15 degrees, and up a foot to address the neck shadow, and place the nose shadow directly downwards. I also dealt with the 'discomfort' of direct light, as looking down the nose of those CFLs can be distracting in close quarters. So using a simple Y adaptor, I was able to angle the CFLs to prevent direct lighting and rely more on reflected lighting from the housing. There are folks here whom are just starting out, and I, like you, wish to convey that it's not about going into debt trying to get 'the kit' in order to do the job. It's about the application and thinking things through. Being a problem solver, starting with the basics and working from there. There really is no magic to this, just lots of practice and patience. So yeah, $50 bucks might have been a stretch, and maybe a $100 for a few more lights would be a better start. I highly recommend those starting out to check out Nino Gianotti's website epflighting.com. That will give you the visuals needed to get started. What I've done here is apply similiar techniques with $50 of Home Depot goodness. So, no more excuses.
__________________
Pete Ferling http://ferling.net It's never a mistake if you learn something new from it. ------------------------------------------- |
April 10th, 2007, 08:32 AM | #37 | |
Trustee
|
Quote:
BTW, Andrew I'm interested in learning more about these new high output LEDs. They speak compact to me. Any pictures?
__________________
Pete Ferling http://ferling.net It's never a mistake if you learn something new from it. ------------------------------------------- |
|
April 13th, 2007, 05:09 AM | #38 |
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
|
How about a fluorescent spiral in a worklight fixture with barndoors attached. Looks confusingly like a video light almost doesn't it. LOL...
On the 60w LED I'll post pictures soon of the LED and the fixture I've chosen for it too. Last edited by Richard Andrewski; April 13th, 2007 at 05:18 AM. Reason: add a picture |
April 13th, 2007, 07:28 AM | #39 |
Regular Crew
Join Date: Jul 2005
Posts: 110
|
Update. I just shot an outside situation where senior management of a mall was demonstrating (to corporate) how traffic was being controlled during their huge construction projects. Anyhow, the sun was at an unflattering position, could not use reflectors. I used one of my cfl spiral boxes on half power and run off an inverter in my car. Voila! no harsh shadows.
The CFL's are very viable and useful. Gary |
April 13th, 2007, 06:51 PM | #40 |
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
|
That's great. The normal expectation is that you need an HMI to do that kind of work outside.
|
April 13th, 2007, 07:34 PM | #41 |
Major Player
Join Date: Feb 2007
Location: Seattle WA
Posts: 420
|
|
April 13th, 2007, 08:53 PM | #42 |
Trustee
Join Date: Nov 2005
Location: Sauk Rapids, MN, USA
Posts: 1,675
|
Just finished adding barndoors to my clamps
Note the ACDelco neck attachment is by bolt, not by friction knuckle...I've gone through 10 of the knuckle based lights, but still use the same 5 ACDelcos! Paint is high heat paint for grill interiors. Bulbs are CFL GE Softwhite bulbs. They have wattage equivs up to 250 tungsten watts. |
April 13th, 2007, 09:50 PM | #43 |
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
|
Wow, good job. Just like the one I did ;-). So your bulbs are drawing 60 actual watts? That's a pretty big one. Didn't know there were GE ones that big yet.
Looks like you decided to use all rivets. I'll be interested to hear how that goes. I found that with the thin aluminum fixtures, its better to attach the hinges to the worklight with machine screws, nuts and lock washers. More secure. Also, looks like you decided not to add the compression spring and wing nut to one side of each hinge. Sometimes I found that the rivets (after much movement of the barndoors) become too loose and the upper and lower barndoors (which are subject to gravity more don't stay in place as well). Hence the reason for adding a machine screw, compression spring and lock washer on one side of the hinge and rivet on the other. Allows tightening up the movement should it get too loose. If you have time, could you post those pictures in my forum under the user articles DIY section? See link below: http://www.coollights.biz/forum/index.php?board=6.0 |
April 14th, 2007, 06:18 AM | #44 |
Regular Crew
Join Date: Jul 2005
Posts: 110
|
Yes Mark that's it. I put 5 100watt daylight (5500k) in one circuit and 4 100watt 3500k in the other circuit.
Gary |
April 14th, 2007, 07:52 AM | #45 |
Trustee
Join Date: Nov 2005
Location: Sauk Rapids, MN, USA
Posts: 1,675
|
I don't have the screws because the hardware store was closed when I decided I wanted the screws...they're open now and pop rivets are both cheap and easy to remove...after one night, I've already got some play in one of my hinges, so I'm switching it over.
|
| ||||||
|
|