adamhiram
No longer a newbie, moving up!
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- #136
Here is a series of tests I did to attempt to determine what is causing the grid spot to not be perfectly round.

20200121-DSC_6741a by adamhiram, on Flickr
Here are some shots of the reflector and grid showing how they fit together. It seems like a pretty decent fit, although perhaps there is some slight light leakage around the perimeter, or the pull-tab is affecting things somehow?

20200121-DSC_6759a by adamhiram, on Flickr
Lastly, here is the 20° grid. Nothing special to see here, but I thought I would include it in this post.

20200121-DSC_6769a by adamhiram, on Flickr
A few questions I still have
- Row 1: Bare reflector. This is just the bare 7" reflector positioned 18" from the background. The light pattern is perfectly round, and doesn't change significantly when I rotate it in the mount. This suggests that there is nothing wrong with the reflector.
- Row 2: Try a different light. This is the same as the first, but with a different strobe. Again, nice round light pattern and no significant changes when rotating the reflector in the mount. This rules out any issues with the light.
- Row 3: Insert grid. This is where I start to see the anomaly. For this test I inserted the grid, then rotated the reflector with the grid in it. The first shot is the most noticeable, with the grid's pull-tab positioned on the top and the light pattern looking a bit lemon shaped. The other two shots aren't perfectly round, but seem a little better.
- Row 4: Rotate grid. This is the same as the third, but only rotating the grid and not the reflector. This produced the same results, implicating the grid as the culprit.

20200121-DSC_6741a by adamhiram, on Flickr
Here are some shots of the reflector and grid showing how they fit together. It seems like a pretty decent fit, although perhaps there is some slight light leakage around the perimeter, or the pull-tab is affecting things somehow?

20200121-DSC_6759a by adamhiram, on Flickr
Lastly, here is the 20° grid. Nothing special to see here, but I thought I would include it in this post.

20200121-DSC_6769a by adamhiram, on Flickr
A few questions I still have
- Are there any issues I am missing with the reflector or grid?
- Does the fit look okay with the grid mounted in the reflector? Are there any concerns with the pull-tab blocking some of the light?
- Most importantly, will the slight distortion in the shape of the grid spot make any difference in real world scenarios?