Which Would You Choose?

zx-m · 07-23-2008, 11:50 AM

Peter: Congratulations on both your ME Supers and your 4,000th post.

I am glad they tested well against your meter--one never knows how this will go. When I am testing a new camera against my Sekonic L308S, I tend to be a little nervous. So far, my new purchases have tested well. I do not use a gray card, though, when testing. I probably should. I suppose I have a fair idea as to what a neutral test subject is, but I have been thinking of buying a set of gray cards anyway. I have looked around a bit, and there does not seem to be much available.

Regards,
Glen

Peter Zack · 07-23-2008, 04:27 PM

Glen, There are some decent and relatively cheap gray cards on Ebay if you can't find one locally. I got my latest one at a local store. They are only good for about 2 years or so as the dye fades.

jgredline · 07-23-2008, 04:46 PM

if I may show my ignorance, what is the purpose of gray cards?

**rparmar** · 07-23-2008, 05:27 PM

Originally posted by jgredline

if I may show my ignorance, what is the purpose of gray cards?

If you meter off one you can set your white balance so it is exactly as grey. Prevents colour casts.

titrisol · 07-24-2008, 12:51 AM

To make sure your meter is metering as it should
The light meter is calibrated for ana average scene, thus balanced light and dark tones, so if you point your camera to a white surface or to a black surface the metering will over/under expose and thus using a grey card allows you to meter correctly.

making one yourself is relatively simple with a printer and paper, you can either do it as a solid gray or I think a black/white checker pattern is best.

IMHO if you are testing the camera meter against a handheld it does not matter what do you test it against as long as it is the same for the handheld and the camera. If you point both to the wall of your house (white in this example) or point both to a dark steel door (black) both should meter the same, and a picture should give you a medium gray in both cases
So point them to an average scene in you backyard and they should meter the same. BUT do it at different times, since the problems arise in both limits of the metering spectrum so a very bright and a quite dark scenes would test the meter best.

Originally posted by jgredline

if I may show my ignorance, what is the purpose of gray cards?

From Clemson tech photography course

Quote:

There are a number of technical situations where camera meter systems will be fooled and produce incorrect exposures. These situations include photographing black and white line drawings, graphs etc and photographing specimens where a white or black background is employed. Specimens photographed in front of a curved background will appear to float in the photograph (see the photograph of the copy stand below) and there will be no background details to distract from the specimen. Consider the three photographic subjects below. The left and right frames will fool the meter systems and thus require exposure reading using a 18% gray card. The middle subject is close to neutral or 18% gray and would produce a correct aperture-shutter setting.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
you choose	deadprez	Pentax SLR Lens Discussion	10	09-01-2009 12:39 PM
Which would you choose?	PaddlesUp	Pentax DSLR Discussion	4	07-19-2009 01:46 PM
Choose one of 3 please	LaRee	Post Your Photos!	40	07-15-2008 09:40 AM
Which would you choose ...	J.Scott	General Talk	28	01-24-2008 04:15 AM
If you had to choose between these two	jgredline	Pentax SLR Lens Discussion	3	11-25-2007 01:03 AM

07-23-2008, 11:50 AM	#16
zx-m Veteran Member Join Date: May 2008 Location: Virginia Posts: 376 Original Poster	Peter: Congratulations on both your ME Supers and your 4,000th post. I am glad they tested well against your meter--one never knows how this will go. When I am testing a new camera against my Sekonic L308S, I tend to be a little nervous. So far, my new purchases have tested well. I do not use a gray card, though, when testing. I probably should. I suppose I have a fair idea as to what a neutral test subject is, but I have been thinking of buying a set of gray cards anyway. I have looked around a bit, and there does not seem to be much available. Regards, Glen

07-23-2008, 04:27 PM	#17
Peter Zack Pentaxian Moderator Emeritus Join Date: May 2007 Location: Edmonton Alberta, Canada Photos: Gallery \| Albums Posts: 10,643	Glen, There are some decent and relatively cheap gray cards on Ebay if you can't find one locally. I got my latest one at a local store. They are only good for about 2 years or so as the dye fades.

07-23-2008, 04:46 PM	#18
jgredline Veteran Member Join Date: Oct 2007 Location: LosAngeles, Ca. Photos: Albums Posts: 10,628	if I may show my ignorance, what is the purpose of gray cards?

07-23-2008, 05:27 PM	#19
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,819	Originally posted by jgredline if I may show my ignorance, what is the purpose of gray cards? If you meter off one you can set your white balance so it is exactly as grey. Prevents colour casts.

07-24-2008, 12:51 AM	#20
titrisol Pentaxian Join Date: Dec 2007 Location: In the most populated state... state of denial Photos: Gallery \| Albums Posts: 1,852	To make sure your meter is metering as it should The light meter is calibrated for ana average scene, thus balanced light and dark tones, so if you point your camera to a white surface or to a black surface the metering will over/under expose and thus using a grey card allows you to meter correctly. making one yourself is relatively simple with a printer and paper, you can either do it as a solid gray or I think a black/white checker pattern is best. IMHO if you are testing the camera meter against a handheld it does not matter what do you test it against as long as it is the same for the handheld and the camera. If you point both to the wall of your house (white in this example) or point both to a dark steel door (black) both should meter the same, and a picture should give you a medium gray in both cases So point them to an average scene in you backyard and they should meter the same. BUT do it at different times, since the problems arise in both limits of the metering spectrum so a very bright and a quite dark scenes would test the meter best. Originally posted by jgredline if I may show my ignorance, what is the purpose of gray cards? From Clemson tech photography course Quote: There are a number of technical situations where camera meter systems will be fooled and produce incorrect exposures. These situations include photographing black and white line drawings, graphs etc and photographing specimens where a white or black background is employed. Specimens photographed in front of a curved background will appear to float in the photograph (see the photograph of the copy stand below) and there will be no background details to distract from the specimen. Consider the three photographic subjects below. The left and right frames will fool the meter systems and thus require exposure reading using a 18% gray card. The middle subject is close to neutral or 18% gray and would produce a correct aperture-shutter setting.