rb61
Loc: Maple Grove, MN
There are several downloadable targets available. I have not seen any instructions as to the best stock, finish, etc for printing them. Although these targets are probably not equal to the higher quality ones that start at $250, I would like to get the best reproduction as possible to test a tele zoom to see if the issue is me trying to handhold it and what it is capable of on a tripod.
Any suggestions?
Thanks
rb61 wrote:
.........
Any suggestions?
Use a newspaper ? Not joking.
Given that you're doing a hand
held test, you're
not testing the
lens, you're testing yourself. So
an actual
Lens Testing Chart is
not really needed.
.
I've used gloss photo paper with good results.
--
TriX
Loc: Raleigh, NC
`
Lens test charts have patterns that
are designed to reveal astigmatism,
CA, distortion, yada yayahahayada ...
None of that is involved here. All that
need be revealed is a degree of detail
streaking, from image motion during
the exposure. Thoroughly ball up and
crinkle some aluminum foil, flatten it
back out and harshly illuminate it. All
those contrasty tiny highlights will rat
out unsteadiness much better than a
paper chart that's primarily designed
to accentuate optical flaws.
But, if you do insist on downloading
test targets, consider that you don't
really hafta print them for the tests
you have in mind. Just display them
on your monitor. For your hand held
steadiness trials, this would work at
least as well as paper prints ... and
very likely even better.
.
TriX
Loc: Raleigh, NC
User ID wrote:
...Just display them
on your monitor. For your hand held
steadiness trials, this would work at
least as well as paper prints ... and
very likely even better...
The max printing resolution of a good printer such as the Pro 100 is MUCH higher than even the best display.
TriX wrote:
The max printing resolution of a good printer such as the Pro 100 is MUCH higher than even the best display.
Since the test target is only black and white not even gray I would think a laser printer gives better result than an inkjet.
Thanks...I,too, am wondering about the source of my problem. This will be a great help.
Print with out editing on semi gloss or hi gloss at your printers max resolution.
rb61 wrote:
There are several downloadable targets available. I have not seen any instructions as to the best stock, finish, etc for printing them. Although these targets are probably not equal to the higher quality ones that start at $250, I would like to get the best reproduction as possible to test a tele zoom to see if the issue is me trying to handhold it and what it is capable of on a tripod.
Any suggestions?
Thanks
I assume from what you wrote that you mean to test using a tripod to find out if any problems you get while handheld are a result of technique or equipment calibration. I do not think that reproduction quality matters that much, as long as you use a decent paper. You will be looking at relative differences and fringing. If the best exposure and focus is right on the focus line it is not equipment. The advantage to the kits for this activity is the ability to accurately line up the angled calibration ruler with the plane of the focus target. Making sure the target is parallel to the image sensor is on you.
TriX
Loc: Raleigh, NC
dsmeltz wrote:
...The advantage to the kits for this activity is the ability to accurately line up the angled calibration ruler with the plane of the focus target. Making sure the target is parallel to the image sensor is on you.
Which is the beauty of the FoCal system. If he used that instead of subjectively guessing about the ruler and the target, he’d have a 4 digit number of acuity for the exposure(s), with and without a tripod, and he could compare that performance (accurately) with other lenses and at different apertures. Rule 1 of making good measurements is to have accurate, precise, and calibrated equipment to perform the measurement.
The fact is that userid’s comment is pretty spot on. If he just wants to know if hand holding vs a tripod is the answer, then the smallest print he can find, taped to a wall, is a good answer. I have found that the folded up disclaimers with prescriptions are a good choice - very small and printed pretty well. On the other hand, if he wants to understand in depth why he isn’t getting the results he expects, then an accurate system, such as Reikan’s FoCal is invaluable. You’d think I worked for them as many times as I’ve endorsed their product, but it’s just so damn good.
TriX wrote:
Which is the beauty of the FoCal system. If he used that instead of subjectively guessing about the ruler and the target, he’d have a 4 digit number of acuity for the exposure(s), with and without a tripod, and he could compare that performance (accurately) with other lenses and at different apertures. Rule 1 of making good measurements is to have accurate, precise, and calibrated equipment to perform the measurement.
The fact is that userid’s comment is pretty spot on. If he just wants to know if hand holding vs a tripod is the answer, then the smallest print he can find, taped to a wall, is a good answer. I have found that the folded up disclaimers with prescriptions are a good choice - very small and printed pretty well. On the other hand, if he wants to understand in depth why he isn’t getting the results he expects, then an accurate system, such as Reikan’s FoCal is invaluable. You’d think I worked for them as many times as I’ve endorsed their product, but it’s just so damn good.
Which is the beauty of the FoCal system. If he use... (
show quote)
But, I think, the OP wants to know if it is his technique or the camera that is causing issues. To do that, the user has to be removed from the equation. A tripod and remote trigger does that while hand holding does not.
FoCal is an excellent product though.
I prefer a test target because it gives you quantified resolution ( a number). First test the lens alone. I do this by working in a darkened room with a flash. Open the shutter, wait a second or two, fire the flash by hand. Now, with this baseline for the lens alone, you can add anything that reduces resolution: shutter and mirror shake, VR, hand holding , and measure (quantify) the difference. You can also find out which apertures are sharpest. I find that I can read the results on my camera (Nikon D800e) as well as on my computer.
TomV
Loc: Annapolis, Maryland
I bought one off of ebay for about $20 a while back. Has a fine B&W herringbone pattern. Also included a 2nd sheet of colored images for reference.
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