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Messages - LowBloodSugar

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Thanks for sharing!  Seems like a solid workflow...

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Lighting / Re: photographing paintings that have thick paint
« on: April 29, 2013, 06:55:43 PM »
Thank you for your thoughtful response.  I am excited to try your suggestions.

My shots from before were coming in with significant glare.   The polarization filter that you suggest will minimize that.  I was using an umbrella diffuser to help get even illumination, but that will have to be removed because the umbrella diffuser will "mix up" the polarized light from the flashes and turn it into unpolarized light.

I have been using the "X-Rite color Checker Passport" and that is producing great results and it is straightforward to use (as long as you are operating in a controlled laboratory like manner).

Thanks again.


I shoot a lot of art for a number of clients, galleries & artists. If the works can be described as having dark, glossy, heavy impasto surfaces, I quote at least twice as much as I would for completely flat work. It's a bitch.

For works up to a couple of meters on the long side, I use two Einsteins with the standard 8 inch reflector, with polarizing gels on the lights. The lights are set back 3-5 meters at 45 degrees to the work, just like on a copy-stand. I also have a polarizing filter on the lens. Shoot tethered so you can have a very clear look at what you're doing. Even a very small adjustment to the light alters the result. It's very important that both lights and modifiers are 100% identical. Make sure you can work in a BIG space.

If there are multiple works, set up an easel and bring the works to your setup. If you move your setup for each work it will take you weeks to do what you can do in a day.

If there are still blown highlights/catchlights in the dark impasto areas, they can be fixed in post in a variety of ways. On an adjustment layer you can hit "dust & scratches" and/or "despeckle" and brush in the trouble spots through a layer mask. Or you can use the color range tool to select the blown areas, feather a tiny bit and literally paint them in. Or a combination of all these things. Remember to just reduce the blown areas till it looks good, not kill them completely or you take away the fact that it is a heavy impasto work. It's a tightrope.

Color? Get yourself an X-Rite color Checker Passport and use as directed. Trust the numbers more than what you perceive. If the works are framed, watch out for shadows thrown on the work by a deep frame.

Dark, glossy, heavy impasto paintings are the hardest of all. Good luck. If the work is important, and you feel it is beyond you at your current skill level, it may be best to pass on the job, skill up and start pitching to prospective clients again later. It's an area that looks simple but is full of traps for the unwary and inexperienced.

-PW

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Lighting / photographing paintings that have thick paint
« on: April 21, 2013, 11:14:06 PM »
I just moved this thread, because i had previously posted it in the wrong forum.

I am trying to build the ultimate setup for photographing a collection of art.  Mostly large oil paintings (3feet x 4feet +/-)  with significant impasto (thickly applied paint that has depth and 3D shape).  There is also hand painted dinner and dessert plates that are glossy.

After much research and trail runs my list of goals are as follows:

1) Maximize sharpness
2) Maximize contrast
3) Maximize resolution
4) minimize vignetting
5) minimize distortion
6) minimize chromatic aberration
7) minimize out of focus fringing
8 ) minimize camera shake AND camera vibration
9) minimize glare,
10) reproduce accurate color
11) maximize uniformity

unknowns:
what is the best angles to put lights so that the paintings self shadowing looks the best (45, 45 copy table style is often recomended, but i think it produces unnatural looking shadows on the paint structure)
should lights be large or small ( soft shadows or sharp shadows )


so far this is the setup that I am thinking will produce the best results:

CAMERA: Canon 5DMK3 (currently owned) on a sturdy tripod or copy table
Set to mirror lockup and shooting raw

Lens:  I have been using a Canon 50mm MK2 1.8 lens with great results but I am considering upgrading to   100mm 2.8L macro IS, or 100mm 2.8 macro, or 135mm 2.8L.  Obviously in this situation a "flat field" prime lens will produce the best results.  I am expecting something like a 5.6 or so aperture will be the best.

Color treatment: xrite color checker passport <- for color calibration (highly recommended).  Use color calibration to get color correct, and don't do any other tweaks.

LIGHTING:
Currently this is the most nagging question for me.  i am using lowelpro continuous lights which have a high color rendering index.  I am experimenting with one or two set with a diffusion umbrella at about 45 degrees.  And one or two lights without diffusion to produce sharper soft shadowing.  But im worried that the shutter speed is just too long and also it produces uneven lighting and camera vibration is still present even on a tripod.  I am thinking that possibly i could switch to using strobes witch would reduce vibration.   I am also considering the wesscot grid flash modifier for creating highly directional and uniform lighting or moving the strobes very far away and not using any modifiers.

ALSO, i am wondering if i should be shooting in a black room or white room.

I am also doing what I can to reduce flare by looking at the histogram and goboing the lights just to make sure i am not getting any issues from off frame lights spilling into the lens.

Do any of the canon rumor members have any advice or experience to share for photographing paintings that have thick paint?

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Pricewatch Deals / Re: EF 24-105 f/4L IS for $770 Shipped
« on: April 21, 2013, 09:04:17 PM »
people in a forum were complaining this was a bad deal because you can fine then on craigslist and eBay and Fred Miranda for less.   but I don't see spending and extra 500  on the kit  to sell it for six hundred.

Yeah, exactly.  It amazing how financially liquid L lenses are.  I traded my t3i + EF 24-105 F4L IS + EFS 17-55 2.8  IS for a year of maid service on two condos!

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Lenses / Re: Why some lens says "macro"?
« on: March 23, 2013, 01:08:38 AM »
The 8-15mm fisheye zoom achieves 0.39x mag!

WARNING:  Objects in fisheye are closer than they appear.

Be very careful.

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Lenses / Re: IS or no IS?
« on: February 07, 2013, 07:54:11 PM »
I am in the market for an IS lens for indoor photo and video work.  IS is a must for me.

I am considering:
Canon 24-105 f/4L IS
Tamron 24-70 2.8 VC
Canon 35 F2 IS

I just rented the Tamron 24-70 IS from lens rentals, and liked it.  Its a bit big.  IS worked well, but its not a magic.  You still have to hold still when hand holding the camera.

I had the efs 17-55 2.8 IS and it was really amazing lens, but incompatible with full frame.

Does anyone know of any websites that show comparison of IS on various lenses for video?  Are some IS lenses able to absorb more motion than others?


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Lenses / Re: Help with 360º Panoramas
« on: January 17, 2013, 05:39:15 AM »
Hi,
I want to take 360º panoramas with my 5D. Can I use the sigma 15mm rectangular fisheye or will I need a circular fisheye?
If it can be done with the sigma 15mm rectangular fisheye, how many shots wilI I need?

Thanks.

Hello,
You can make a 360 pano with any lens, but the wider it is the easier.  I am guessing you are talking about a 15mm fisheye.

The sigma 15mm produces a image circle centered on the image plane and the edges at the left and right on a full frame sensor.  The top and bottom are cut off.  To create a 360, the easiest is the rotate the camera into portrait mode, and take 6 images in a circle.    If you have a crop sensor camera, the image will produce about a 180 fov across the diagonal, so it will take more photo to cover the full visual field.

I decided on the Canon 8-15mm F/4 zoom for my 360 Panos, which by the way is may favorite lens.

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Lenses / Re: Your favorite lens is?
« on: January 15, 2013, 03:29:08 AM »
jcollett,

I just sold my t3i, 17-55 2.8 IS, and my soul to buy a 5DMK3 so I can capture low light video on the 8-15mm f/4L.  This lens deserves the best.


On crop camera, my favorite is the Canon 8-15 f/4L.  Full frame, I think I will love it even more.  The only thing I don't like about it is the lens cap.

If true, then your next purchase MUST be a FF camera.  Get a used 5Dc or 5D mark ii ASAP even if you need to sell other stuff to get it.  Once you see the 8-15 on a FF, the crop sensor camera you have now may never get used again!

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Lenses / Re: Your favorite lens is?
« on: January 14, 2013, 03:50:16 AM »
On crop camera, my favorite is the Canon 8-15 f/4L.  Full frame, I think I will love it even more.  The only thing I don't like about it is the lens cap.

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EOS Bodies / Re: DSLR & Lens Coming on January 15, 2013? [CR1]
« on: January 12, 2013, 07:23:05 PM »
People love using the live view mode, when testing cameras.  I would guess it would be something with IS.  That feature is easy to demo and it really sells itself.

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PowerShot / Re: Canon Announces The PowerShot N
« on: January 07, 2013, 04:38:43 PM »
I am contemplating the flash.
Looks like an led flash, which normally dont work well because the led is on for the entire duration or the image. They do not freeze a photo but have the benefit of being useful for video.

Also the drawback of the led flash is maybe a non issue with a lens that is optically stablized.

It's seems like a really good combo.

I wonder if this will be compatible with the new ex rt flashes.

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